Control System

Fm

Comfort
Controller
CC 6400

Remote communication
over telephone network

Fm

Comfort
Controller
CC 6400

Carrier
Management
Terminal

Open protocols network (subject to availability)

High speed multi-terminal

management network

Installation, operation and maintenance instructions

CONTENTS

1 - SAFETY CONSIDERATIONS ................................................................................................................................................ 4

1.1 - General ............................................................................................................................................................................... 4
1.2 - Precautions against electrocution ...................................................................................................................................... 4
1.3 - General installation recommendations .............................................................................................................................. 4
1.4 - Conformity ......................................................................................................................................................................... 4
2 - GENERAL DESCRIPTION .................................................................................................................................................... 4
2.1 - Scope of application ........................................................................................................................................................... 4
2.2 - General ............................................................................................................................................................................... 4
2.3 - Technical terms ................................................................................................................................................................... 5
3 - DETAILED DESCRIPTION .................................................................................................................................................... 5
3.1 - Architecture ........................................................................................................................................................................ 5
3.1.1 - Installing equipment ................................................................................................................................................ 5
3.1.2 - Architecture with one or more controllers .............................................................................................................. 5
3.1.2.1 - Slave configuration between controllers .................................................................................................. 5
3.1.2.2 - Controller addressing ................................................................................................................................ 6
3.1.3 - Architecture with Building Management System ................................................................................................... 6
3.1.4 - Architecture with one or more Power Modules ...................................................................................................... 7
3.1.4.1 - Slave configuration between Power Modules ........................................................................................... 8
3.1.4.2 - Power Module addressing ......................................................................................................................... 8
3.1.5 - Technical characteristics of the communication systems ....................................................................................... 8
3.1.5.1 - Secondary bus ........................................................................................................................................... 8
3.1.5.2 - Local bus ................................................................................................................................................... 8
3.1.5.3 - Zui bus ....................................................................................................................................................... 10
3.1.5.4 - Adding line termination impedance .......................................................................................................... 10
3.2 - The Maestro controller ....................................................................................................................................................... 10
3.2.1 - Controller outputs .................................................................................................................................................... 11
3.2.2 - Controller inputs ...................................................................................................................................................... 11
3.2.2.1 - Input for ON/OFF contact ......................................................................................................................... 12
3.2.2.2 - Input for window contact/operating fault contact in condensate pump ................................................... 12
3.2.2.3 - Room temperature sensor (accessory) ...................................................................................................... 13
3.2.2.4 - Return air sensor (accessory) .................................................................................................................... 15
3.2.2.5 - Temperature sensors for changeover, hot leaving water and chilled leaving water (accessories) ........... 16
3.2.3 - How the Maestro controller operates ...................................................................................................................... 17
3.2.3.1 - How the controller operates in Occupied mode ....................................................................................... 17
3.2.3.2 - How the controller operates in Unoccupied mode ................................................................................... 19
3.2.3.3 - How Defrost mode operates ...................................................................................................................... 20
3.2.3.4 - Setpoint reset ............................................................................................................................................. 20
3.2.3.5 - Determining the temperature to control ................................................................................................... 21
3.2.3.6 - Correcting the measured temperature ....................................................................................................... 21
3.2.3.7 - Changeover mode ...................................................................................................................................... 21
3.2.3.8 - Overriding the actuators ............................................................................................................................ 21
3.2.3.9 - Load shedding ........................................................................................................................................... 21
3.2.3.10 - Mail waiting and outdoor temperature indicator .................................................................................... 21
3.2.4 - Assigning parameters to the Maestro controller ..................................................................................................... 22
3.2.4.1 - Parameter assignment tools ....................................................................................................................... 22
3.2.4.2 - Configuring the FACTORY parameters .................................................................................................... 22
3.2.4.3 - Configuring the SERVICE parameters ..................................................................................................... 23
3.2.4.4 - Configuring the SETPOINT parameters ................................................................................................... 23
3.2.4.5 - Configuring the identification and system parameters ............................................................................. 23
3.2.4.6 - Configuring the alarm management parameters ....................................................................................... 24
3.2.4.7 - Configuring the timetable parameters ...................................................................................................... 24
3.2.4.8 - Controller maintenance variables ............................................................................................................. 24

The cover photographs are for illustration only, and have no contractual significance whatsoever.
The manufacturer reserves the right to change the appearance and design of the units at any time without notice.
2

CONTENTS (contd)

3.2.5 - Initialising a controller with its default parameters ................................................................................................ 26

3.2.6 - Restarting a controller after a mains power failure ................................................................................................. 26
3.2.7 - Controller operation LED ........................................................................................................................................ 26
3.2.8 - Alarms ...................................................................................................................................................................... 26
3.2.9 - Troubleshooting ....................................................................................................................................................... 26
3.2.10 - Controller connections .......................................................................................................................................... 26
3.2.10.1 - Controller power supply .......................................................................................................................... 26
3.2.10.2 - Actuator output connections ................................................................................................................... 27
3.2.10.3 - Input connections .................................................................................................................................... 27
3.2.10.4 - Connecting the communication buses .................................................................................................... 27
3.2.11 - Technical characteristics ....................................................................................................................................... 29
3.2.11.1 - Electrical characteristics ......................................................................................................................... 29
3.2.11.2 - Mechanical characteristics ...................................................................................................................... 29
3.3 - The user interface (accessory) ............................................................................................................................................ 30
3.3.1 - The Zone User Interface .......................................................................................................................................... 30
3.3.1.1 - Description ................................................................................................................................................ 30
3.3.1.2 - Zone User Interface connections .............................................................................................................. 31
3.3.1.3 - Technical characteristics ........................................................................................................................... 32
3.3.2 - Wall-mounted thermostat ........................................................................................................................................ 32
3.3.2.1 - Description ................................................................................................................................................ 32
3.3.2.2 - Wall-mounted thermostat connections ...................................................................................................... 33
3.3.2.3 - Technical characteristics ........................................................................................................................... 33
3.4 - The Power Module ............................................................................................................................................................. 34
3.4.1 - The external Power Module .................................................................................................................................... 34
3.4.1.1 - Outputs ...................................................................................................................................................... 34
3.4.1.2 - Inputs ......................................................................................................................................................... 34
3.4.2 - The internal Power Module ..................................................................................................................................... 36
3.4.2.1 - Outputs ...................................................................................................................................................... 36
3.4.2.2 - Inputs ......................................................................................................................................................... 36
3.4.3 - Communication buses ............................................................................................................................................. 36
3.4.4 - Assigning parameters to Power Modules ................................................................................................................ 37
3.4.4.1 - Parameter assignment software tool ......................................................................................................... 37
3.4.4.2 - Configuring the SYSTEM parameters ...................................................................................................... 37
3.4.4.3 - Configuring the SERVICE parameters ..................................................................................................... 37
3.4.4.4 - MAINTENANCE variables ...................................................................................................................... 37
3.4.5 - Restarting a Power Module after a power failure ................................................................................................... 37
3.4.6 - Troubleshooting ....................................................................................................................................................... 38
3.4.7 - Power Module connections ..................................................................................................................................... 38
3.4.7.1 - Power Module power supply ..................................................................................................................... 38
3.4.7.2 - Connections to input devices .................................................................................................................... 38
3.4.7.3 - Connections to output devices .................................................................................................................. 38
3.4.7.4 - Powering up a Power Module ................................................................................................................... 40
3.4.8 - Technical characteristics ......................................................................................................................................... 40
3.4.8.1 - Electrical characteristics ........................................................................................................................... 40
3.4.8.2 - Mechanical characteristics ........................................................................................................................ 40
3.5 - The Floor Manager (Fm) .................................................................................................................................................... 41
3.6 - Typical configurations ........................................................................................................................................................ 41
3.6.1 - Architecture with controller .................................................................................................................................... 41
3.6.1.1 - Assigning parameters to controllers .......................................................................................................... 42
3.6.2 - Architecture with controllers and Power Modules .................................................................................................. 53
3.6.2.1 - Assigning parameters to controllers .......................................................................................................... 43
3.6.2.2 - Assigning parameters to Power Modules .................................................................................................. 45

1 - SAFETY CONSIDERATIONS

1.1 - General
Installing, commissioning and servicing the various components
which make up the Maestro control system can be dangerous
unless certain aspects of the system are taken into account,
such as the presence of mains electricity and hot or chilled
water in the air conditioning equipment.
Only specially trained technicians and installers who have
been fully trained on the product concerned are authorised to
install, commission and service this equipment.
During servicing work, it is essential to apply all the recommendations and instructions given in service leaflets, on labels or
in the instructions delivered with the equipment, and to
comply with any other relevant safety notices.
It is important to comply with all the safety rules and regulations
currently in force. Wear eye protectors and work gloves.
Take extreme care when moving or positioning equipment.
1.2 - Precautions against electrocution
Only electricians who are qualified to the level recommended
by the IEC (International Electrotechnical Commission) in its
standard IEC 364, corresponding to Europe HD 384, France
NFC 15 100 and UK IEE Wiring Regulation, may have access to
electrical components. In particular it is obligatory to disconnect
all electrical power supplies to the unit or its accessories
before carrying out any work. Disconnect the main power
supply with the standard isolating switch (not supplied by
Carrier).
IMPORTANT: The components which make up the Maestro
control system include items of electronic equipment. As such,
they may generate or be disturbed by electromagnetic interference unless they are installed and used in accordance with
these instructions. The components making up the Maestro
control system conform to the requirements of electromagnetic
compatibility in residential and industrial areas. They also
comply with the low-voltage directive.
1.3 - General installation recommendations
IMPORTANT: There must be a power disconnection device
upstream of the controller and Power Module (this may take
the form of a double-pole circuit breaker, for instance). If
necessary, an easily operated emergency stop device (such as
a punch-button switch) must cut off the power to all
equipment. These safety devices shall be dimensioned and
installed in accordance with IEC Recommendation 364,
corresponding to Europe HD 384, France NFC 15 100 and
UK IEE Wiring Regulation. These devices are not supplied by
Carrier.
IMPORTANT: When replacing a Maestro controller please
verify the configuration of the variable or three-speed type
fan motor assembly, before connecting it to the controller.
In general terms the following rules must be applied:

The power disconnection device must be clearly labelled

to identify which items of equipment are connected to it.

The wiring for the components which make up the Maestro

control system and for the communication buses must be
carried out in accordance with the state of the art by
professional installers.
4

The components which make up the Maestro control

system must be installed in an environment which conforms
to their index of protection (IP) (see chapters 3.2.11.2
Mechanical characteristics of the controller, and 3.4.8.2
Mechanical characteristics of the Power Module).
The maximum level of pollution is normally pollutant
level 2 and installation category II.

The low-voltage wiring (communication bus) must be

kept physically separate from the power cabling.
In order to avoid interference with the communication
links:
Keep low-voltage wiring away from power cables
and avoid using the same cable run (a maximum of
300 mm in common with the 230 V AC, 30 A cable).
Do not pass low-voltage wires through loops in the
power cables.
Do not connect heavy inductive loads to the
electrical source used as the power supply for
controllers and Power Modules (circuit breaker).
Use the screened cable type recommended by
Carrier and keep all cables connected to their
respective controllers and Power Modules (see
chapters 3.2.10 Connecting controllers, and 3.4.7
Connecting Power Modules). This list is not
exhaustive.

1.4 - Conformity
This equipment has been declared to be in conformity with the
main requirements of the directive by virtue of using the
following standards:

Electromagnetic compatibility: 89/336/EEC

Low-voltage directive: 73/23/EEC

2 - GENERAL DESCRIPTION
2.1 - Scope of application
The Maestro control systsem is designed to control air conditioning systems of the terminal unit type:

two-pipe or four-pipe,

with or without electric heater,

with three-speed or variable speed fan motor.

2.2 - General
The Maestro control system controls room temperature by
opening or closing water valves and/or adjusting an electric
heater and the fan speed.
In cooling mode, the controller adjusts a chilled water valve
and the fan speed in order to keep the ambient temperature at
the setpoint for the air conditioned space.
In heating mode, the controller adjusts a hot water valve and/or
an electric heater and the fan speed in order to keep the ambient
temperature at the setpoint for the air conditioned space.
The Defrost mode enables the air conditioning unit to maintain a
minimum room temperature, and a feature known as Drying
mode ventilates the room at the maximum fan speed and
maximum heat.

With two-pipe systems, the method of switching between

heating and cooling can be determined by an input known as
Changeover.
The Maestro control system is designed to work in either of
two different operating modes:

The MASTER operating mode, in which the terminal unit

is controlled by commands entered on the Zone User
Interface (microterminal) or wall-mounted thermostat.

The SLAVE operating mode, in which several terminal

units are controlled by one or more microterminals or
wall-mounted thermostats.
In both these operating modes, the controller can be
overridden by commands from the CCN (Carrier Comfort
Network).
The command device may be a Carrier Floor Manager (Fm)
for instance, or a Carrier Building Management System
(Comfort-Works).
In combination with a Power Module (Pm), the Maestro
control system has the following options:

Directly controlling a lighting source,

Managing a controlled output (socket),

Raising, lowering and adjusting the angle of window blinds.

There is a software tool for setting parameters and configuring
the Maestro control system.
2.3 - Technical terms
The following abbreviations are used in this document:
AI
: Analogue Input
AO : Analogue Output
BMS : Building Management System
CCN : Carrier Comfort Network
DI
: Digital Input
DO : Digital Output
Fm : Floor Manager
LED : Light-Emitting Diode
NC : Normally Closed
NO : Normally Open
Pm : Power Module
Zc
: Zone Controller
Zui : Zone User Interface (microterminal)
3 - DETAILED DESCRIPTION

Depending on the application, one or more slave modules (Zc

and/or Pm) may be used with the system in order to control the
temperature of a large space and/or to handle several lighting
sources, sockets and window blinds.
3.1.1 - Installing equipment
The various devices which make up the Maestro control
system are located in physically different places within the
building:

Zone Controller (Zc): This is factory-fitted to the inside

or outside of the terminal unit. These units are generally
located in machine rooms, false ceilings or false walls in
the air conditioned zone.

Power Module (Pm): This is generally installed in a false

floor, false ceiling, hollow section or machine room.

Zone User Interface microterminal (Zui): This can be

fitted inside the terminal unit, wall-mounted, or desk-top.

Wall-mounted thermostat: Always fitted to an internal

wall.

Floor Manager (Fm): This is generally located in an

electrical enclosure containing a power supply and
connections for the primary and secondary buses.
3.1.2 - Architecture with one or more controllers
Several controllers can coexist on a single communication bus
called the secondary bus. Each controller is allotted a unique
address on the bus. This distinguishes it from other controllers
and enables it to be recognised and configured.
When several terminal units are used to provide air conditioning
to a single zone, it is essential to organise them into a single
group in order to ensure that they do not work against one
another.
To do this, a master/slave relationship has to be created between
the controllers on each terminal unit. This slave configuration
is then supported by a secondary communication bus interconnecting the controllers.
3.1.2.1 - Master/slave configuration between controllers
There is a configuration parameter which enables the status of
each controller to be defined (master with slave, master
without slave, or slave) and each slave controller to be given
the address of its master.
In a master/slave system all controllers operate with the same
setpoint, reference temperature and operating mode. The
reference temperature taken into account is always that of the
master controller.

3.1 - Architecture
The minimum control system consists of a control module (Zc)
and a temperature sensor (not supplied by Carrier).

The master/slave controller concept is transparent to the end

user.

This system may be combined with a microterminal (Zui) or a

wall-mounted thermostat.
A Power Module (Pm) may be added to the system in order to
handle a lighting source, a controlled output (socket) and
window blinds.

Secondary bus

Master

Slave

Zui bus

Zui bus

Slave

Zone A

Master

Others

Zui bus

Zui bus

Zone B

Typical architecture: Zc Maestro control system + Zui

3.1.2.2 - Controller addressing

Two decimal coding wheels located under the transparent
window on the casing are used to define the network address
for the controller.
Each address must be unique on the secondary bus concerned.
A controller can have one of 128 different addresses (in the
range 1 to 128).
The first coding wheel (SW1) selects the units: 0, 1, 2, 3, 4, 5,
6, 7, 8, 9.
The second coding wheel (SW2) selects the tens: 0, 10, 20, 30,
40, 50, 60, 70, 80, 90.

The micro-switch (SW3) located below the coding wheels,

particularly its selector switch labelled 4, selects the hundred:
0 (ON position), 100 (OFF position).
To be taken into account, the network address must be configured with power down.
3.1.3 - Architecture with Building Management System
Controllers may be connected upstream, either directly to the
Carrier Building Management System in the case of a system
using a limited number of controllers, or through a Floor
Manager that groups a large number of controllers together
(large-scale system).
IMPORTANT: The controller with secondary bus address 1
is made responsible for acknowledging messages from the
Floor Manager (Fm).
It is therefore essential that each system has a controller with
1 as the address.

Controller coding wheels SW1 and SW2, and microswitch SW3

6

Primary bus

BMS

Fm

Fm

Slave

Master

Key:
Fm
Floor Manager
Zc
Zone Controller
Zui
Zone User Interface
(microterminal)
BMS Building Management System

Secondary bus

Zui bus

Slave

Zui bus

Zui

Others

Slave

Zui

Zui bus

Zui bus

Zui

Zui

Zone A

Typical architecture: BMS MAESTRO control system + Fm + Zc + Zui

3.1.4 - Architecture with one or more Power Modules
If Power Modules have been installed to control lighting sources
and window blinds, a communication bus known as the Local
Bus is used to connect the Power Modules to the controllers.

If a controller is linked to one Power Module, the Zone User

Interface is connected directly to the Power Module over the
Zui bus.

Primary bus (optional)

Fm (optional)
Secondary bus
Master Zc

Slave Zc

Other Zcs

Master Zc

Other Zcs

Master Zc

Other Zcs

Local bus 1
Local bus n
Master Pm

Slave Pm

Slave Pm

Other Pms
Local bus 2

Zui bus

Zui bus

Zui bus

Master Pm

Zui bus
Zui

Key:
Fm Floor Manager
Zc Zone Controller
Pm Power Module
Zui Zone User Interface
(microterminal)

Zui

Other Pms

Master Pm

Zui bus

Zui bus

Zui

Zui

Zui

Zui

Typical architecture: Zc MAESTRO control system +Pm + Zui

7

3.1.4.1 - Master/slave configuration between Power Modules

Several Power Modules have to be used in a single zone if
there are several lighting sources or window blinds to control.
If several Power Modules are installed in the same zone, one
Power Module shall be declared as the master and the others as
slaves.
If only one Power Module is associated with the controller, it
shall be declared master.
There is a configuration parameter which enables the status of
each Power Module to be defined (master, slave No. 1, slave
No. 2, slave No. 3, slave No. n).
3.1.4.2 - Power Module addressing
Two decimal coding wheels located under the transparent
window on the casing are used to define the network address
for the Power Module on the local bus.

3.1.5 - Technical characteristics of the communication

systems
3.1.5.1 - Secondary bus
A secondary bus supports a maximum of 128 controllers.
The maximum number of slave controllers associated with a
master controller is 127.
The communication network uses RS485 three-wire links +
screening (cable: two pairs + screening 9/10).
Maximum secondary bus distance: 1500 metres.
The communication protocol over the bus is Carrier Comfort
Network (CCN).

A Power Module can have one of 99 different addresses (in the

range 1 to 99).

RECOMMENDATIONS FOR INSTALLATION:

Ensure that the bus screening is continuous on each item

of equipment connected.

Connect one end of the bus screening to system earth.

Connect both ends of the bus screening to system earth if

the earths are identical.

Avoid star cabling with any branch longer than 1.5

metres.

The first coding wheel (RS1) selects the units: 0, 1, 2, 3, 4, 5,

6, 7, 8, 9.

3.1.5.2 - Local bus

A local bus supports a maximum of 60 connection nodes.

The second coding wheel (RS2) selects the tens: 0, 10, 20, 30,
40, 50, 60, 70, 80, 90.

A node can be a controller or a Power Module.

Each Power Module network address must be unique on the

local bus concerned.

To be taken into account, the network address must be configured

with power down.
Additional software addressing has to be carried out on Power
Modules so that they can communicate with the controller to
which they are attached.
There is a configuration parameter for setting up the association
between a controller and a Power Module.

A local bus can include several Power Modules and the same
number of master controllers.
The maximum number of slave Power Modules that can be
associated with a master Power Module is 58:

Given that there are 60 available nodes on a local bus, the

distribution is as follows:
1 controller
1 master Power Module
58 slave Power Modules
The communication network uses RS485 three-wire links +
screening (cable: two pairs + screening 9/10).
Maximum local bus distance: 1500 metres.
The communication protocol over the bus is Carrier Comfort
Network (CCN).
RECOMMENDATIONS FOR INSTALLATION:

Ensure that the bus screening is continuous on each item

of equipment connected.

Connect one end of the bus screening to system earth.

Connect both ends of the bus screening to system earth (if

the earths are identical).

Avoid star cabling with any branch longer than 1.5

metres.

Power Module coding wheels RS1 and RS2

Cable screening to
be connected to
building earth
Zone
Controller
side

Secondary bus

Bus side

Secondary bus wiring diagram

Detail Power
Module side
local bus

Detail Zone
Controller side

local bus

Cable screening to
be connected to
building earth

Not supplied by
Carrier

Note crossed wires

between Pm and Zc

Local bus wiring diagram

3.1.5.3 - Zui bus

The Zui bus connects a Zone User Interface (microterminal) to
a controller or to a Power Module.
It can support only one Zone User Interface.

Adding line termination impedance to the local bus

The Zc controller has a micro-switch (SW3) located under the
transparent window in the casing:

When the selector switch labelled 1 on the controller

printed circuit is in the ON position, the local bus is
polarised with an impedance of 120 Ohms.

The Zui bus communication system uses RS485 (two-wire) +

two-wire power supply (cable: two pairs 9/10 + screening).

The default position for selector switch 1 of micro-switch

SW3 is OFF.

Maximum Zui bus distance: 50 metres.

The Power Module has a micro-switch with two selector
switches, located under the transparent window in the
casing:

RECOMMENDATION FOR INSTALLATION: If the cable

distance is greater than 5 metres, connect the link screening
controller side or Power Module side to system earth.

Communication protocol: SENSOR INPUT/OUTPUT (SIO)

3.1.5.4 - Adding line termination impedance
Adding line termination impedance enables the bus to be
polarised. This may prove necessary if communication problems
arise on the local or secondary bus.

When it is in the ON position, the local bus is polarised

with an impedance of 120 Ohms.
The default position for this selector switch is OFF.

IMPORTANT: Line termination impedance should not be

added to the bus unless absolutely necessary.

In all cases one and only one device shall be configured to add
line termination impedance to the bus. This shall generally be
the last device on the bus.

Power Module micro-switch in OFF position

3.2 - The Maestro controller
Zc micro-switch SW3
Adding line termination impedance to the secondary bus
The Zc controller has a micro-switch (SW3) located in the
upper left part of the card:

When the selector switch labelled 2 on the controller

printed circuit is in the ON position, the secondary bus is
polarised with an impedance of 120 Ohms.
The default position for selector switch 2 of micro-switch
SW3 is OFF.

This contains the control program for adjusting the water

valves and fan motor on the terminal unit by reference to
setpoint temperature and ambient temperature.
It also manages information received from other temperature
sensors (return air sensor, room temperature sensor, changeover
sensor), as well as information received by its logical inputs
(window contact, remote On/Off contact (occupied/unoccupied)
on the controller).
It communicates with its slave controllers over the secondary
bus, with Power Modules over the local bus, with the Zone
User Interface over the Zui bus, and with both the Floor Manager
(Fm) and the Carrier ComfortWorks supervisor over the
secondary and primary buses.

10

The controller is available in two models:

Controller for water applications with the following

configurations:
Two pipes
Two pipes with changeover
Four pipes

Controller for water/electric heater applications with the

following configurations:
Two pipes/two wires
Two pipes/two wires with changeover
Four pipes/two wires

The permitted ways in which this equipment can be combined

are described below:
Two pipe terminal unit
Permitted configuration
Additional
heating

Two-pipe

Cooling

Heating

Fan motor

with
changeover

Water valve

Water valve

with
changeover

Water valve

Water valve

PTC electric
heater

with
changeover

Water valve

Water valve

Shielded
Three-speed
electric heater

with
changeover

Water valve

Water valve

Water valve

without
changeover

Water valve

without
changeover

Water valve

PTC electric
heater

Three-speed or
variable speed

without
changeover

Water valve

Shielded
electric heater

Three-speed

Three-speed or
variable speed
Three-speed or
variable speed

Three-speed or
variable speed
Three-speed or
variable speed

Four-pipe terminal unit

Permitted configuration

Zc controller with cover to client terminal strip open

The main functions of the controller are:

Controlling room temperature. Temperature is measured

either by the temperature sensor incorporated in the Zone
User Interface microterminal or in the wall-mounted thermostat, or by a room temperature sensor or return air sensor,

Selecting OCCUPIED or UNOCCUPIED mode through

the Zone User Interface, the wall-mounted thermostat or
the Floor Manager,

Controlling the OCCUPIED setpoint through the Zone

User Interface or the wall-mounted thermostat,

Controlling room air renewal (through Zone User

Interface only),

Halting the control function if an open window is detected.

3.2.1 - Controller outputs
The devices that can be connected to the controller outputs are
as follows:

A variable speed fan motor or three-speed fan motor, with

single-phase power supply from the Zc controller,

One, two or three water flow control valves of the on/off

type, with single-phase power supply from the Zc
controller,

A PTC or shielded electric heater, with single-phase power

supply from the Zc controller.

Four-pipe

Cooling

Heating

without
changeover

Water valve

Water valve

without
changeover

Water valve

Water valve

without
changeover

Water valve

Water valve

without
changeover

Water valve

Water valve

Additional
heating

Fan motor
Three-speed or
variable speed

PTC electric
heater
Shielded
electric
heater
Water valve

Three-speed or
variable speed

Three-speed

Three-speed or
variable speed

The connectors on the controller which are needed for making

links with the various components are to be found at the
locations indicated overleaf on the terminal strip.
3.2.2 - Controller inputs
The devices that can be connected to the controller inputs are
all passive and optional. They are as follows:

A return air or room temperature sensor: 10 kOhms at 25C,

A changeover temperature sensor or hot water leaving

temperature sensor: 10 kOhms at 25C,

A chilled water leaving temperature sensor: 10 kOhms at

25C,

A potentiometer (0 to 100 kOhms) for resetting the setpoint value (wall-mounted thermostat),

A dry contact for determining window status or detecting

an operating fault in the condensate pump on the terminal
unit,

A dry contact for affecting OCCUPIED or UNOCCUPIED

controller mode,

A dry contact for placing a safety restriction on heating

output or additional heating output in the case of a shielded
electric heater.

11

Controller terminal strip

3.2.2.1 - Input for ON/OFF contact

A dry ON/OFF contact, such as from an external clock, can be
connected to this input.
This is a Normally Open type of contact.
In this case, a change of state (from open to closed and from
closed to open) alters the operating mode of the controller. A
change must be maintained for at least two seconds before its
status is taken into account by the controller.
Changing from the closed to the open state causes the controller
to change to unoccupied mode.
Changing from the open to the closed state causes the controller
to change to occupied mode.

12

3.2.2.2 - Input for window contact/operating fault contact

in condensate pump
The Zc controller can detect the current status of the windows
in an air conditioned zone and/or an operating fault in a condensate pump on the terminal unit, and alter its operating mode as
a result.
If it detects that a window is open or that the water level in the
condensate drain pan has reached the alarm threshold, the
controller switches to defrost mode. It returns to its original
mode when the window contact or condensate drain pan have
returned to normal status.
Note that the controller takes account of the status of windows
in accordance with air conditioning regulations relating to
buildings in the service sector.

In order to avoid short-term changes, the controller only changes

to defrost mode one minute after a window has been opened. On
the other hand it changes to defrost mode as soon as it detects
a threshold alarm from the condensate drain pump. The
previous operating mode returns as soon as the contact has
switched back to its initial status.
The direction in which this input works can be defined by
parameter:

NO: Normally Open =>

Window closed or condensate drain pan level
correct: contact open
Window open or condensate drain pan at alarm level:
contact closed

NC: Normally Closed =>

Window closed or condensate drain pan level
correct: contact closed
Window open or condensate drain pan at alarm level:
contact open

The master controller takes account of only the first eight

messages indicating that a window is open (each must be from
a different slave controller), and further messages are ignored:

If a window that has been taken into account returns to its

initial status, the next message indicating that a window
is open will be taken into account (provided it is from a
slave controller other than the seven already stored).
If more than eight windows are open and the eight
windows taken into account return to their initial status at
the same time, the master controller will leave defrost
mode. It may return to it the next time data is exchanged
with its slaves (in about 5 min.).

Master/slave architecture and operating fault contact in

condensate pump:
If a slave controller detects that the water level in the condensate
drain pan has reached the alarm threshold, then only this controller switches to defrost mode and an alarm is generated (in
accordance with the alarm parameters).

Factory setting: Normally Open

Several windows can be connected to the same input.
In the case of NC logic, the contacts are to be cabled in series.
In the case of NO logic, the contacts are to be cabled in parallel.
Master/slave architecture and window contact:
If a slave controller detects a change of status in any of its
windows, it sends this information to the master controller. The
master controller and its slave controllers then switch to
defrost mode.
If another slave controller detects a change of status in any of
its windows, it also sends this information to the master
controller.
The master controller stays in defrost mode until all windows
have returned to their initial status.

The settings displayed on the Zone User Interface microterminal

which is connected to this controller stay unchanged; all air
conditioning commands are still authorised and will be sent to
the other controllers. Defrost mode stays active on this
controller until the water level in the condensate drain pan
falls below the alarm threshold (i.e. until the condensate drain
pan water level contact returns to its original position).
3.2.2.3 - Room temperature sensor (accessory)
In the case of a system that has no user interface, the controller
may be connected to a room temperature sensor fixed to the
wall of the air conditioned zone. Choose the location of the
sensor carefully. It is recommended that the sensor should be
placed 1.5 metres above floor level in order to avoid draughts
from doors, windows and air diffusers. Also avoid sources of
direct or indirect heat which can have a negative effect on the
controller. This means keeping the sensor away from direct
sunlight, background heaters, computers etc.

Inside view of sensor

Marking zone

Card

Sensor

Dimensional drawing of the room temperature sensor

13

NOTE: If a room temperature sensor is used on its own, it will

be necessary to connect a programmable clock (not supplied
by Carrier) to the On/Off contact on the controller, or use a
Floor Manager (Fm), in order to change the occupation status
of the premises.
Technical characteristics:

Resistance at 25C: 10 kOhms

Dimensions: 85 x 63 x 23 mm

Colour: 23512-001 (beige)

Fire rating: UL94-V0 (M1)

Operating environment: 0 to 50C.

A single-pair 9/10 cable + screening is required to connect the
room temperature sensor to the Zc controller.
Maximum length of connector cable: 30 metres
Room temperature sensor
No connectors are needed for making the link:

Screw terminals sensor side

Cage clamp clip terminals controller side.

Room temperature sensor

J1
reference mark
T3 on label

Not supplied
by Carrier

Screening to be connected to
the terminal unit

Circuit diagram for room temperature sensor to Zc controller

14

3.2.2.4 - Return air sensor (accessory)

Whether or not the system has a user interface, the controller
may be connected to a return air sensor which is installed in
the return air duct on the terminal unit or in the unit itself.

Technical characteristics:

Resistance at 25C: 10 kOhms

Temperature coefficient at 25C: -4.4%/C

Temperature utilisation range: 0 to 50C

Sensor dimensions: length 26 mm, diameter 7 mm.

In this case, system control is based on the return air temperature.

NOTE: If a return air sensor is used on its own, it will be
necessary to connect a programmable clock (not supplied by
Carrier) to the On/Off contact on the controller, or use a Floor
Manager (Fm), in order to change the occupation status of the
premises.

The return air sensor consists of a stainless steel sensing

element protected by a heat-shrunk sleeve, fitted with a singlepair cable 2 metres long (wire section 0.22 mm2 multi-strand,
ends tinned 8 mm).
No connectors are needed for making the link:
Cage clamp clip terminals controller side.

J1
reference mark
T3 on label

Circuit diagram for return air sensor to controller

15

3.2.2.5 - Temperature sensors for changeover, hot leaving

water and chilled leaving water (accessories)
In a two-pipe application the controller may be connected to
what is known as a changeover temperature sensor.
The measured temperature enables the controller to determine
whether the water circulating in the system is hot (i.e. above a
certain threshold temperature which is definable by parameter)
or cold. It can then authorise the appropriate heating or
cooling control mode.

Technical characteristics:

Resistance at 25C: 10 kOhms

Temperature coefficient at 25C: -4.4%/C

Temperature utilisation range: 0 to 50C

Sensor dimensions: length 26 mm, diameter 7 mm.

Temperature sensors for changeover, hot leaving water and
chilled leaving water consist of a stainless steel sensing element
protected by a heat-shrunk sleeve, fitted with a single-pair
cable 2 metres long (wire section 0.22 mm2 multi-strand, ends
tinned 8 mm).
No connectors are needed for making the link:
Cage clamp clip terminals controller side.

J1
reference mark
T2 on label

Circuit diagram for changeover sensor to controller

16

3.2.3 - How the MAESTRO controller operates

Two occupancy modes are allowed: Occupied mode and
Unoccupied mode.
The occupancy mode can be altered by the Zone User
Interface or the wall-mounted thermostat and/or by the Building
Manage-ment System and/or by a dry contact connected to the
ON/OFF input on the controller.
The Maestro controller offers a choice of seven operating modes:

Off

Cooling

Fan only

Heating

Air change

Defrost

Room drying
The operating mode is determined by the controller by reference
to the measured temperature relative to the configured
setpoint, or by a forced mode or by an external action (such as
window status, changeover mode, etc.).
3.2.3.1 - How the controller operates in Occupied mode
This mode is used to maintain the comfort conditions required
during periods when the air conditioned zone is occupied. To
achieve this, it keeps the temperature within the dead band,
that is, a given range on either side of the displayed setpoint.
The main control parameters are as follows:

Occupied setpoints,

Occupied dead band,

Occupied setpoint reset. This can be altered by means of

the Zone User Interface or wall-mounted thermostat
within a variation range which can be defined by
parameter on either side of the setpoint.
Default value Minimum value

Maximum value

Occupied setpoint

20C

15C

30C

Occupied dead band

2.5C

1C

8C

User permitted reset

1.5C

0C

6C

Desired setpoint - dead band/2

Occupied setpoint
configured

In occupied mode, the following operating modes are managed

by the controller:

Cooling

Fan only

Heating

Air change

Defrost

Room drying
In cooling mode, the chilled water valve output is activated. The
type of control law applied to a variable speed fan is Integrated
Proportional (IP). Fan speed is controlled by phase splitting.
The control law applied to a three-speed fan allows automatic
switching between fan speeds 1, 2 or 3 in relation to ambient
temperature and setpoint.
In fan only mode, the heating and chilled water valve outputs
are disabled.
A variable speed fan delivers the minimum flow rates of cold
and warm air defined in the parameters.
A three-speed fan operates at its minimum speed.
In heating mode, the type of control law applied to the fan is
Integrated Proportional (IP). The heating output is activated.
If additional heating has been configured, it will be used at
maximum capacity if the heat output is not enough to maintain
the temperature within the dead band.
The type of control law applied to a variable speed fan is
Integrated Proportional (IP). Fan speed is controlled by phase
splitting.
The control law applied to a three-speed fan allows automatic
switching between fan speeds 1, 2 or 3 in relation to ambient
temperature and setpoint.

Desired setpoint

Desired setpoint + dead band/2

Temperature

User
reset

Dead band/2

Dead band/2

17

The air change mode is only available with a variable speed

fan. It can only be accessed from the Zone User Interface and
then only when the controller is in OCCUPIED mode.

Control law applied in the case of a three-speed fan:

It provides the air conditioned zone with a rapid air change. This
mode may be cancelled manually at any time, or automatically
after a definable timeout.
While this mode is operating, the fan is activated at maximum
speed (100%) and the cooling valve output is activated.
The defrost and room drying modes take priority over other
operating modes.

Defrost mode is activated if the controller detects that a

window is open or that the water level in the condensate
drain pan has reached the alarm threshold or there is a
BMS command to that effect (see chapter 3.2.3.3 - How
defrost mode operates).

Room drying mode is activated if the controller cannot

read the ambient temperature and if this function is enabled
by the configuration parameter Room Drying Select. This
very special mode consists of activating the fan at
maximum speed and operating the heating output at
maximum capa-city. It is generally used in the final
construction phase of a building (e.g. for drying out
plaster).

Operating
mode

When configured opening time for

chilled or hot water valve has expired

For

Fan
speed
variation

Cooling

If temperature to control > SpCont + 3/8

DBOcc

2 min

+1

Cooling

If temperature to control < SpCont + 3/8

DBOcc

3 min

-1

Cooling

If temperature to control < SpCont +

DBOcc/4

At once

Minimum
speed

Heating

If temperature to control < SpCont - 3/8

DBOcc

2 min

+1

Heating

If temperature to control > SpCont - 3/8

DBOcc

3 min

-1

Heating

If temperature to control > SpCont DBOcc/4

At once

Minimum
speed

Heating

Only if additional heating is configured: If

temperature to control < SpCont DBOcc/2 (fan speed is maximum until
temperature to control exceeds SpCont 3/8 DBOcc) (see next page: functional
diagram of the control)

At once

Maximum
speed

NOTE: In the case of a Zone User Interface the fan speed

selected must be AUTO in order for the controller to apply this
algorithm.

SpCont - DBOcc/4

SpCont + DBOcc/4
SpCont + 3/8 DBOcc

SpCont - 3/8 DBOcc

SpCont

SpCont - DBOcc/2

SpCont + DBOcc/2

Temperature
(C)

Heating output activated

Cooling valve output activated

Time 2

Time 1

Fan output controlled by algorithm

Fan output controlled by algorithm

Time 3

Additional heating output activated

Heating mode

Fan only mode

Key:
SpCont = Occupied Setpoint + User Reset
DBOcc = Occupied Dead Band

Cooling mode

Time 1: Waiting time before authorisation to use fan algorithm in cooling mode
Time 2: Waiting time before authorisation to use fan algorithm in heating mode
Time 3: Waiting time before authorisation to use additional heating

Functional diagram showing how occupied status is adjusted

The fan is kept at its minimum configured speed in cooling
mode:

from point SpCont+DBOcc/4 (cooling mode)

to point SpCont-DBOcc/4 (heating mode).

Similarly, the fan is kept at its minimum configured speed in
heating mode:

from point SpCont-DBOcc/4 (heating mode)

to point SpCont+DBOcc/4 (cooling mode).

The fan speed selected shall be AUTO when switching from
unoccupied to occupied mode.
18

Special case of a shielded coil as a heating element:

In heating mode, and up to a point in the shielded coils capacity equal to 50% of its maximum capacity, for safety reasons
the minimum authorised fan speed shall be the intermediate
speed (speed 2). Beyond this 50% of maximum capacity, the
only authorised fan speed shall be maximum speed (speed 3).

3.2.3.2 - How the controller operates in Unoccupied mode

This mode is generally used in order to reduce energy consumption during periods when the air conditioned zone is unoccupied.

Default value Minimum value Maximum value

Unoccupied setpoint

20C

Unoccupied dead band 10C

This mode can be enabled from the Zone User Interface

(micro-terminal), the wall-mounted thermostat or the BMS.

15C

30C

2.5C

14C

The main control parameters for this mode are as follows:

Unoccupied setpoint

Unoccupied dead band.

Setpoint - dead band/2

Setpoint + dead band/2

Configured setpoint

Temperature

Dead band/2

Dead band/2

In UNOCCUPIED mode, the following operating modes are

managed by the controller:

Cooling

Off

Heating

Defrost

Room drying

In heating mode, the heating output is activated.

If additional heating has been configured it will also be activated.
A variable speed fan delivers the maximum flow rate of warm
air defined in the parameters.
A three-speed fan delivers warm air at its maximum speed.

In the Off mode, the fan is stopped and the outputs for heating
and cooling are disabled.
In cooling mode, the output for the chilled water valve is
activated.
A variable speed fan delivers the maximum flow rate of cold
air defined in the parameters.
A three-speed fan runs at its maximum speed.

The defrost and room drying modes take priority over other
operating modes.

Defrost mode is activated if the controller detects that a

window is open or that the water level in the condensate
drain pan has reached the alarm threshold or there is a
BMS command to that effect (see chapter 3.2.3.3 - How
defrost mode operates).

Room drying mode is activated if the controller cannot

read the ambient temperature and if this function is enabled
by the configuration parameter Room Drying Select. This
very special mode consists of activating the fan at
maximum speed and activating the heating output.
SpUnocc + 1/2 DBUnocc - e

SpUnocc - 1/2 DBUnocc + e

SpUnocc + 1/2 DBUnocc

SpUnocc - 1/2 DBUnocc

SpUnocc

e
Temperature

Cooling valve output activated

Heating output activated

Fan max. cooling flow

Fan max. heating flow

Heating mode

Key:
SpUnocc: Unoccupied Setpoint
DBUnocc: Unoccupied Dead Band
e: Hysteresis 1C

Off mode

Cooling mode

Functional diagram showing how unoccupied status is adjusted

19

Special case of a shielded coil as a heating element:

For safety reasons, the fan is only allowed to stop after running
for a further 40 sec. at minimum speed after the shielded coil is
switched off.
Special case of a return air temperature sensor:
The fan is activated to run at its maximum speed for 6 minutes
every 40 minutes in order to measure the ambient temperature.
This is not a configurable option.
3.2.3.3 - How Defrost mode operates
This mode is used to place the air conditioned zone on defrost
status. The mode may be activated from either OCCUPIED or
UNOCCUPIED status.

Defrost mode is activated if the controller detects that a

window is open or that the water level in the condensate
drain pan has reached the alarm threshold or there is a
BMS command to that effect.

The controller returns to its previous operating mode when the

window is closed or when the water level in the condensate
drain pan falls below the alarm threshold or when the BMS
cancels defrost mode.

A variable speed fan delivers the maximum flow rate of warm

air defined in the parameters.
A three-speed fan operates at its maximum speed.
Above the defrost setpoint + hysteresis, the fan is stopped and
the outputs for heating and for the chilled water valves are
disabled.
3.2.3.4 - Setpoint reset
The value of the setpoint can be changed from the user interface during OCCUPIED mode.
Seven reset steps are allowed:
one null position
(reset = 0),
3 positions above 0 (reset = 1, 2 or 3),
3 positions below 0 (reset = -3, -2 or -1)
The controller multiplies the reset value by the reset step value
and adds the result to the setpoint:
Setpoint = Setpoint in occupied mode + (Reset x Reset step
value)

The main control parameter for this mode is the defrost

setpoint.

Defrost setpoint

Below defrost setpoint the heating and additional heating

outputs are activated at their maximum capacity.

Default value

Minimum value

Maximum value

7C

4C

14C

NOTE: The parameters for setpoint in occupied mode and

Reset step value form part of the configuration parameters for
the controller.

SpDF + e

SpDF

Temperature

Heating output open

Fan max. heating flow

Heating mode

Defrost mode

Key:
SpDf: Defrost Setpoint
e: Hysteresis 1C

Functional diagram showing how defrost mode is adjusted

20

3.2.3.5 - Determining the temperature to control

The controller uses either a room temperature sensor or a return
air temperature sensor in order to determine the temperature to
control.
A configurable parameter tells the controller which type of
sensor to use.
REMINDER: In UNOCCUPIED mode, if a return air temperature sensor has been configured, the fan is activated to run at
its maximum speed for 6 minutes every 40 minutes. This is not
a configurable option.
Master/slave architecture:
Slave controllers always take account of the temperature
which the master controller sends them. They therefore do not
need their own temperature sensors.
3.2.3.6 - Correcting the measured temperature
The controller may add a temperature reset (which may be
positive or negative) to the measurement given by the room
temperature sensor or return air temperature sensor, as follows:
Control temperature = Measured temperature +
Temperature sensor correction
NOTE: The control temperature is the temperature which is
required to be maintained.
3.2.3.7 - Changeover mode
The controller can only be operated in changeover mode in the
case of a two-pipe terminal unit with or without additional heating. It allows the controller to operate in cooling or heating mode
using a single water valve that can carry hot or chilled water.
This mode can be validated by means of the permitted changeover configuration parameter.
The controller measures the temperature of the water circulating
through the tubes in the unit with the aid of information it
receives from the water distribution network or by using a temperature sensor (known as the changeover temperature sensor).

NOTE: The threshold temperature is a configurable

parameter.
Master/slave architecture:
Slave controllers always take account of the changeover temperature which the master controller sends them. They therefore
do not need their own changeover sensors.
3.2.3.8 - Overriding the actuators
Overriding (forcing) enables the system to check that the various
components in the unit are working correctly, and to assist in
the adjustment and commissioning of a system (for instance
balancing the hot and chilled water circuits in a building).
Overriding an actuator takes priority over the current operating
mode. The current mode is permitted to resume control of the
actuator when override mode is cancelled.
Actuators may only be overridden from the BMS, the Floor
Manager or the parameter assignment software tool. This
applies to the following:

the fan speed,

the heating and cooling valve outputs

the additional heating output.

3.2.3.9 - Load shedding
The controller includes a load shedding function.
If this is not authorised (default), current load shedding
information has no effect on heating and additional heating.
If it is authorised and the current load shedding information is
Yes (default), then heating or additional heating will not be
authorised if they are the PTC electric heater or shielded
coil type.

If the heating is the electric heater type, fan and off

modes are active in occupied and unoccupied mode
respectively.
If the additional heating is the electric heater type,
heating mode is authorised and only the heating output
(hot water valve) will be activated.

In this way the controller determines a changeover mode

which is appropriate to the operating modes it can deliver
(cooling or heating).

Overriding the current load shedding information to No allows

heating or additional heating of the PTC electric heater or
shielded coil type to be authorised.

NOTE: Information received from the water distribution network takes priority over a reading from a temperature sensor.

NOTE: Defrost and room drying modes are unaffected by the

load shedding function.

In changeover mode, the laws governing the operating modes

in OCCUPIED or UNOCCUPIED mode remain the same.
Note however that if the operating mode and the changeover
mode are incompatible, the controller will stay in ventilation
only mode (if the mode is OCCUPIED) or Off (if the mode is
UNOCCU-PIED) until changeover mode is able to satisfy the
demand.

3.2.3.10 - Mail waiting and outdoor temperature indicator

This information is written by an override from a BMS system.
The controller does not use this information, which is quite
simply transmitted to the Zone User Interface to be displayed.

The following decision logic enables the controller to determine

its changeover mode:
IF Changeover Temperature < Threshold Temperature
THEN
Changeover Mode = Cooling
ELSE Changeover Mode = Heating
END

IMPORTANT: These overrides are not saved or backed up by

the controller, and will therefore be lost in the event of a loss
of mains power.

Note that displaying the outdoor temperature depends on a

configuration parameter.

21

3.2.4 - Assigning parameters to the Maestro controller

The Zc controller must be configured in accordance with the
terminal unit to which it is fitted, the system it serves and the
requirements of the customer:
When assigning parameters to the Maestro controller it is
possible to do the following:

Declare which operator interface is to be used (Zui

microterminal or wall-mounted thermostat)

Declare the zone temperature measurement mode

Declare whether a Power Module is present

Declare the changeover function

Declare the direction in which the window contact works

(if fitted)

Declare the heating source

Adjust the minimum and maximum rates of air flow in

heating and cooling modes

Modify the various setpoints

(This list is not exhaustive)
When assigning parameters, there are essentially six different
parameter types:

FACTORY parameters, which depend on the type of

terminal unit used.

SERVICE parameters, which depend on the customers

system,

SETPOINT parameters, which determine the desired

control range,

IDENTIFICATION AND SYSTEM parameters, which

depend on the customers system,

ALARM parameters, which also depend on the customers

system,

TIMETABLE parameters, which enable alarms to be

dated and time-stamped.
Thereafter, maintenance variables keep us informed of the
controllers operating status and the status of the outputs from
the Power Modules connected to it. The concept of authorised
overriding is in fact based on these parameters. Overriding can
apply to:

the controllers outputs (overriding actuators),

activating defrost mode,

refreshing the variable representing the outdoor

temperature,

activating the mail waiting indicator,

indicating the changeover temperature to the controller.

IMPORTANT: When the controller has been configured, it is
essential to power it down and then up again before use,
other-wise it may not function exactly as expected.

3.2.4.1 - Parameter assignment tools

When there are very few units to be configured (twenty or less),
the controller may be configured with the Carrier Network
Service Tool (not supplied) over the secondary bus (by Carrier
Service only).
With this tool, English is the default language. If parameter
names are required in French, the Native Language parameter
has to be changed in the controller (see chapter called Configuring the factory parameters) and the controller must then be
remotely reloaded in its entirety.
If there are many terminal units to be configured (over 20), it is
preferable to use the Maestro configuration tool from Carrier
(not supplied) over the secondary bus (currently available in
French and English).
3.2.4.2 - Configuring the FACTORY parameters
Parameter

Description

Default
value

Fan type

0/1 (0 = variable speed/1 = three-speed)

Type of fan motor connected to terminal
unit.

Cool Enable Duration

0 to 1800s
This parameter allows the fan motor
0
command to take place at a different time in
relation to the valve opening command.
0/1/2/3 (0 = none/1 = PTC electric heater/2
= shielded electric heater/3 = water valve)

Heat Type

Heat Enable Duration

CAUTION: A shielded electric heater must

always be installed with a three-speed fan.
A PTC electric heater may be installed with
either type of fan.

0 to 1800s
This parameter allows the fan motor
0
command to take place at a different time in
relation to the valve opening command.
0/1/2/3 (0 = none/1 = PTC electric heater/2
= shielded electric heater/3 = water valve)

Additional Heat Type

CAUTION: A shielded electric heater must

always be installed with a three-speed fan.
A PTC electric heater may be installed with
either type of fan.

CLWT Sensor Present

No/Yes
Defines whether there is a sensor for the
0
Chilled Leaving Water Temperature (CLWT)
on the terminal unit.

HLWT/CHG Sensor
Present

No/Yes
Defines whether there is a sensor for the
0
Hot Leaving Water Temperature (HLWT), or
for changeover (CHG).

0/1/2/3 (0 = window contact normally

open/1 = window contact normally closed/2
0
Window/Drain Pan Type = drain pan contact normally open/3 = drain
pan contact normally closed).

Factory Test Info

8 ASCII characters
Information about the test carried out in the
factor y.

CAUTION: This parameter can be written to

the controller once only.

Native Language

22

0/1 (0 = English/1 = French)

English is the default language. If
parameters are required in French, this
parameter must be changed in the
controller, and the controller must then be
remotely reloaded in its entirety.

3.2.4.3 - Configuring the SERVICE parameters

3.2.4.4 - Configuring the SETPOINT parameters

Default
value

Parameter

Description

Master Address

0 to 128 Master/Slave configuration

- Parameter = 0: controller is master without a slave.
- Parameter = controller address (coding wheel):
controller is master with slaves.
0
- Parameter does not equal controller address (coding
wheel): controller is slave and this parameter is the
address of the master.

Local Bus Device

Type

0/1/2 (0 = Power Module/1 = none/2 = Zone User

Interface microterminal).
Describes the type of device connected over the
controller's local bus or Zui bus.

Room Drying Select

0/1/2 (0 = never/1 = only when the user interface is

disconnected/2 = always authorised).
Defines when room drying mode is authorised.

Loadshed Enabled

No/Yes
Defines whether load shedding function is authorised.

No

Control Temp
Sensor

0/1 (0 = room temperature sensor/1 = return air

temperature sensor)
Defines the type of temperature sensor used to control 0
room temperature. The room temperature sensor is in
the Zone User Interface when this is connected.

-7.0 to 7.0C
Correction applied to the return air or ambient
temperature measurement (reset).
This correction enables a positive or negative reset to
be permanently applied to the room temperature or
return air temperature sensor reading.

0.0

Delta T Control
Select

(Not applicable)

Changeover Enable

0/1 (No/Yes)
Defines authorisation of changeover mode (applies to
two-pipe terminal unit only)

Threshold
Temperature

10 to 40C
The threshold temperature for changeover mode.
Below threshold temperature, the water is treated as
cold and the controller is authorised to operate in
cooling mode.
Above threshold temperature, the water is treated as
hot and the controller is authorised to operate in
heating mode.

18

Enable Delay

0 to 30 min
Delay before authorising additional heating to be
star ted.

Purge Duration

1 to 15 min
Duration of room air renewal mode.
During this period the chilled water valve is activated
and the fan motor is operated at its maximum speed
(100%).

Cooling Minimum
Speed

20 to 80% of maximum speed

Minimum speed of variable speed fan when operating
in cooling mode.

Heating Minimum
Speed

20 to 80% of maximum speed

Minimum speed of variable speed fan when operating
in heating mode.

Cooling Maximum
Speed

Control Sensor Bias

Parameter

Description

Default
value

Occupied Setpoint

15.0 to 30.0C
Setpoint for occupied mode

20.0

Occupied Dead Band

1.0 to 8.0C
Dead band for occupied mode

2.5

Unoccupied Setpoint

15.0 to 30.0C
Setpoint for unoccupied mode

20.0

Unoccupied Dead Band

2.5 to 14.0C
Dead band for unoccupied mode

10.0

Frost Protect Setpoint

4.0 to 14.0C
Setpoint for defrost mode

7.0

Setpoint Reset Step

0.0 to 2.0C
Value of setpoint reset step.
The user interface allows the setpoint to be
changed by reset steps. The reset can vary 0.5
from -3 to +3 compared with the setpoint
value. This value is the reset step value
expressed in degrees Celsius.

Delta T CLWT Setpoint

(Not applicable)

12

Delta T HLWT Setpoint

(Not applicable)

40

3.2.4.5 - Configuring the identification and system

parameters
Parameter

Description

Default value

Device Name

8 ASCII characters
The name of the device concerned
(optional)

Description

24 ASCII characters
Description (optional)

Location

24 ASCII characters
Location (optional)

Software Part Number

16 ASCII characters
The last two figures correspond to CSA - SRthe controller version (not
42F22C11
modifiable)

Model Number

20 ASCII characters
(not modifiable)

Serial Number

12 ASCII characters
(not modifiable)

40

Reference Number

24 ASCII characters
(not modifiable)

40

Bus Number

1 to 239
Number of secondar y bus to which 1
the controller is assigned.

30 to 100% of maximum speed

Maximum speed of variable speed fan when operating 90
in heating mode.

Secondary Bus Com

Speed

9600 to 38400 baud

Communication speed over the
secondar y bus.

Heating Maximum
Speed

30 to 100% of maximum speed

Maximum speed of variable speed fan when operating 70
in heating mode.

IMPORTANT: The default bus number is 1.

Proportional Gain
(variable speed fan)

0.0 to 20.0
IP propor tional gain for variable speed fan.

7.0

Integral Gain
(variable speed fan)

0.0 to 5.0
IP integral gain for variable speed fan.

0.7

Proportional Gain
(shielded electric
heater)

0.0 to 20.0
IP propor tional gain for shielded electric heater.

1.0

Integral Gain
(shielded electric
heater)

0.0 to 5.0
IP integral gain for shielded electric heater.

1.0

User Fan Control

Enable

0/1 (No/Yes)
Defines authorisation to select fan speed from Zone
User Interface.

Zui Control Temp

Icon

0/1 (No/Yes)
Defines authorisation to display ambient temperature
on Zone User Interface.

Zui OAT Icon

0/1 (No/Yes)
Defines authorisation to display outdoor ambient
temperature on Zone User Interface.

Zui Window Icon

0/1 (No/Yes)
Defines whether 'window' icon is displayed when
window is open.

Version 1.1

38400

The bus number parameter must be configured for application

architectures which make use of a Floor Manager.
It must be the same as the element number of the Floor
Manager to which it is assigned.

23

3.2.4.6 - Configuring the alarm management parameters

Default
value

Parameter

Description

Re-Alarm Time

0 - 1440 min
Timeout for re-issuing alarms when
they are acknowledged by the BMS.
They will be re-issued at the end of the
0
period specified in this parameter if still
present. If this parameter is set at 0 it
means that no alarms will be re-issued
over the bus after acknowledgement.

Alarm Routing

3.2.4.8 - Controller maintenance variables

The following variables represent the operating status of the
controller. They can only be accessed from Carrier parameter
assignment tools or the Floor Manager.
They are used to check whether the controller is operating
satisfactorily.
Description

Override
possible

Occupied

No/Yes

No

Operating Mode

Purge/Off/Fan/Heating/Cooling/Frost/Drying No

Changeover Mode

None/Cool/Heat

Master/Slave Status

None/Master/Slave
Configured status: Master only/Master with No
Slave(s)/Slave

Variable

0-11111111
This parameter defines the device(s)
that will take alarms generated by the
controller into account and
acknowledge them: 1 = authorised, 0 =
not authorised.
11010000
| b7 | b6 | b5 | b4 | b3 | b2 | b1 | b0 |
bit 7 = 1 => Local alarm (e.g. BMS)
bit 6 = 1 => Autodial Gateway
bit 5 = 1 => OTIS Gateway
bit 4 = 1 => Translator
bit 3 to 0 => Reser ved

No/Yes
Defines whether the Alarm Summar y
message is enabled.
If this parameter is YES, it allows a
single alarm message to be generated
Summary Alarm Enable over the secondar y bus, containing a
No
summar y of all the alarms detected.
If this parameter is NO, the number of
alarm messages generated over the
secondar y bus can be the same as the
number of alarms detected.

Zone Controller Status

No

Temperature Status

Space Temperature

3.2.4.7 - Configuring the timetable parameters

Parameter

Description

Default
value

Time

(00 :00 to 23 :59)

00.00

Day of Week

(1 to 7)
(1: Monday, 2: Tuesday .... 7: Sunday)

...

Holiday Today

0 or 1
Defines public holidays

Month

1 to 12

Day of Month

1 to 31

Year

0 to 99

(nnn.nC)
This is the temperature readout from the
temperature sensor in the Zone User
Interface or the wall-mounted thermostat,
or from the room temperature sensor. It is
expressed in degrees Celsius.

Yes

(nnn.nC)
This is the temperature readout from the
Return Air Temperature
return air temperature sensor. It is
expressed in degrees Celsius.

Yes

Cold Leaving Water

Temp

(nnn.nC)
This is the temperature readout from the
chilled water temperature sensor.
Expressed in degrees Celsius.

Yes

HLWT/Changeover
Temp

(nnn.nC)
This is the temperature readout from the
hot water temperature sensor or
changeover temperature sensor.
Expressed in degrees Celsius.

Yes

Outside Air
Temperature

(nnn.nC)
This value is not a control parameter but is
for information only. It may be displayed on
the Zone User Interface microterminal,
depending on the status of configuration
Yes
parameter "Zui OAT Icon". The only way
this value can be written is by overriding
this entr y in the controller. Expressed in
degrees Celsius.

Control Data Status

NOTE: These timetable parameters are not saved or backed

up.

Control Temperature

(nnn.nC)
This is the return air temperature or room
temperature according to the "Control
Temp Sensor" parameter. A correction may
Yes
be applied to this temperature by the
control sensor bias parameter. This
temperature is the temperature to be
controlled. Expressed in degrees Celsius.

Control Point

(nnn.nC)
This is the Occupied setpoint, reset from
the desired value by the user in Occupied
mode. It is the Unoccupied or Defrost
No
setpoint in Unoccupied mode and Defrost
operating mode respectively. Expressed in
degrees Celsius.

Control Dead Band

(nnn.nC)
This is the Occupied dead band in
Occupied mode. It is the Unoccupied dead No
band in Unoccupied mode. Expressed in
degrees Celsius.

Reset Position

-3 to 3
Number of reset steps from the setpoint
desired by the user.

Reset Value

(n.nC)
Reset value desired by the user, derived
from the product of the "reset position" and No
the value of the "setpoint reset step".
Expressed in degrees Celsius.

If there is a mains power failure, they are lost and will return
to their default values when power is restored.

24

No

Variable

Description

Override
possible

Alarm Status Flags:

This value represents the absence or presence of an alarm.

Cooling Status

b7
On/Off
This determines whether the chilled water
valve is activated.

Yes

Heating Output

On/Off
This determines whether the heating output
is activated (hot water valve or electric
heater).

Yes

Shield Heat Duty Cycle

0 to 100%
Duty cycle for activation of the shielded
electric heater. One cycle equals 5 minutes.
Yes
100% means the heater is activated all the
time. 50% means that the heater is activated
for 2 minutes 30 seconds in every 5 minutes.

Cooling Output

Primary Heat Status

Additional Heat Status

Additional Heat Output

On/Off
This determines whether the additional
heating output is activated (hot water valve
or electric heater).

Yes

b6

b5

b4

b3

b2

b1

b0

b0 = 1 if communication is defective between Zc and Pm or

between Zc and Zui.
b1 = 1 if the value measured by the outdoor temperature
sensor is incorrect.
b2 = 1 if an internal error is detected in the Zc.
b3 = 1 if the Zc is a slave and has not received the control
temperature sent out by the master Zc.
b4 = 1 if the water level in the condensate drain pan has
reached the alarm threshold.
b5 = 1 if the chilled water leaving temperature measurement
is incorrect.
b6 = 1 if the hot leaving water temperature or changeover
temperature measurement is incorrect.
b7 = 1 if an internal error is detected in the Pm.
Zc Status Flags:

Fan Status
Fan Type

Variable/Three Speeds

Fan Mode

Manual/Auto
Fan mode is manual if fan speed is given by
the user from the Zone User Interface and
not by the controller. For the variable speed
No
fan this applies in "Air Renewal" (Purge)
operating mode. For the three-speed fan it
applies when the user selects fan speed 1, 2
or 3.

Three Speed Fan

0/1/2/3
Fan speed on the three-speed fan.
(Stop/Speed 1 (lowest)/Speed 2/Speed 3
(highest))

Yes

Variable Fan Speed

0 to 100%
A fan speed of 100% on the variable speed
fan corresponds to the maximum speed of
the fan motor.
The power supplied to the fan motor is then
equal to the available single-phase mains
voltage.

Yes

Zc Status Flags

(See definition below)

No

Alarm Status Flags

(See definition below)

No

S/S Contact Status

Close/Open
Status of star t-stop contact connected to the Yes
controller (closed/open)

Window/Drain Ct Status

Close/Open
Status of window contact and/or drain pan
alarm threshold contact (closed/open)

Yes

Frost Protect Enable

No/Yes
Defrost mode active yes/no.
This operating mode can be triggered by
overriding this entry in the controller.

Yes

Loadshed In Effect

No/Yes
Validates the load shedding function.
If Yes, heating outputs of the electric heater
type are disabled.
If No, heating outputs of the electric heater
type are authorised.

Yes

b7

Yes

b6

b5

b4

b3

b2

b1

b0

b0 = 1 if the cooling output is in an overridden status.

b1 = 1 if the heating output is in an overridden status.
b2 = 1 if the additional heating output is in an overridden
status.
b3 = 1 if the electric heater is in an overridden status.
b4 = 1 if the fan output is in an overridden status.
b5 = 1 if the air renewal (purge) operating mode is in effect.
b6 = if equals 0 => changeover mode = cooling, if equals 1
=> changeover mode = heating.
b7 = if equals 0 => terminal unit is two-pipe, if equals 1 =>
terminal unit is four-pipe.
The following maintenance variables provide status information
about the lights and controlled outputs (sockets) on the Power
Modules connected to the controller:

General Unit Status

Variable

Description

Power Module Maintenance

Mail Flag

Power Module 1 Light

On/Off
Status of lighting output on master Power Module.

On/Off
Power Module 1 Socket Status of controlled output socket on master Power
Module.
Power Module 2 Light

On/Off
Status of lighting output on slave 1 Power Module.

On/Off
Power Module 2 Socket Status of controlled output socket on slave 1 Power
Module.

No/Yes
This value is not a control parameter but is
for information only. It will be displayed on
the Zone User Interface microterminal as a
Yes
small flashing icon in the form of an
envelope if set at Yes. This value can only be
written by overriding this entry in the
controller.

Power Module 3 Light

On/Off
Status of lighting output on slave 2 Power Module.

On/Off
Power Module 3 Socket Status of controlled output socket on slave 2 Power
Module.
Power Module 4 Light

On/Off
Status of lighting output on slave 3 Power Module.

On/Off
Power Module 4 Socket Status of controlled output socket on slave 3 Power
Module.

NOTE: The default value for load shedding shall be NO if the

load shedding function is not authorised. It is YES if the load
shedding function is authorised.
25

3.2.5 - Initialising a controller with its default parameters

A controller can be reinitialised with its default parameters.
The procedure for this is as follows:
1 - Power down the controller,
2 - Set both of the coding wheels under the transparent
window on the casing to 0, and set switch 4 on the microswitch to the On position,
3 - Power up the controller,
4 - Wait 5 sec until the LED flashes once a second,
5 - Initialisation is finished; power down,
6 - Configure the new address,
7 - The controller is now configured with its default parameters
and ready to be restarted.
3.2.6 - Restarting a controller after a mains power failure
Following a mains power cut the controller restarts in the
occupation mode it had before the power went off.
Timetable parameters are reinitialised at their default values.
No actuators or variables are overridden.
The fan mode is in the AUTO position and the air renewal
operating mode (purge) is deactivated.
The network address given by the two coding wheels on the
controller is taken into account.
3.2.7 - Controller operation LED
A controller continuously tests whether its electronics are
working properly. A red LED fitted to the board can be seen
beneath the transparent cover on the casing and indicates
whether the electronic circuits are operating correctly.
If the LED flashes regularly about once a second, this means
the module is working correctly.
If the LED is flashing rapidly or not at all, the controller is not
working correctly (see chapter 3.2.9 - Troubleshooting).
3.2.8 - Alarms
The controller is capable of detecting malfunctions and issuing
alarm messages over the secondary bus as follows:
Alarm

Description

Alarm 1

Defective communication with the Power Module or Zone User Interface.

This alarm goes away once communication is re-established.

Alarm 2

Incorrect measurement of return air temperature or room temperature. This

alarm goes away when temperature measurement is correct once again.

Alarm 3

Internal Fatal Error in the controller.

Alarm 4

A slave controller has not received a control temperature from the master
controller for 10 min. This alarm goes away when the slave controller once
again receives a control temperature.

Alarm 5

The water level in the condensate drain pan has reached the alarm
threshold. This alarm goes away when the water level in the condensate
drain pan drops below the alarm threshold again.

Alarm 6

Incorrect chilled water leaving temperature. This alarm goes away when the
temperature measurement is correct once again.

Alarm 7

Incorrect hot water leaving temperature. This alarm goes away when the
temperature measurement is correct once again.

Alarm 8

Internal Fatal Error in the Power Module.

Alarm 9

Alarm summary: ALARM 1 + ALARM 2 + ALARM 3 + ALARM 4 + ALARM

5 + ALARM 6 + ALARM 7 + ALARM 8
If the alarm parameter known as "Summary Alarm Enable" is Yes, only this
alarm is sent. This alarm goes away when all other alarms have gone away.

3.2.9 - Troubleshooting
The following table lists the main problems that may be met
and how they can be remedied:
26

Symptom

Remedy

Controller in ventilation 1 - Incorrect controller configuration

only mode instead of
2 - Incompatible changeover mode status
cooling or heating mode 3 - Faulty changeover temperature sensor
4 - Faulty return air or room temperature sensor
5 - User interface disconnected or faulty
6 - Controller is a slave and has not received ambient
temperature
Controller stays in room 1 - Incorrect controller configuration; check configuration
drying mode
of Room Drying Select parameter
2 - Faulty changover temperature sensor
3 - Faulty return air or room temperature sensor
4 - User interface disconnected or faulty
Controller stays in
defrost mode

1 - Incorrect controller configuration; check NO or NC

declaration of window contact
2 - A device (controller or Power Module) has detected an
open window (if window icon is flashing ) or the water
level in the condensate drain pan has reached the alarm
threshold.

Controller operation LED 1 - Faulty PROM

flashing rapidly
Controller operation LED 1 - Faulty board power supply
not flashing
2 - Faulty board fuses
Additional electric
heater command not
working

1 - Incorrect controller configuration; check configuration

of the additional heating parameters
2 - Jumper J8 missing

Zone User Interface not

displaying information

1 - Incorrect controller configuration; check configuration

of Local Bus Device type parameter
2 - Faulty Zui bus connections
3 - Faulty microterminal power supply

Controller in Off
operating mode instead
of room drying

1 - Incorrect controller configuration; check configuration

of Room Dr ying Select parameter
2 - Faulty connections between controller and power
module

Unexpected controller
operation

1 - Controller was not powered down after configuration

Zone User Interface

1 - Defective communication between controller and
mode is Unoccupied but Power Module; check whether one or more devices are
On/Off button for
applying a line termination impedance over the bus.
switching to Occupied
mode not working
Defective
communication with
controller

1 - Check connections
2 - Check controller address (controller bus number
default is 1)
3 - Check communication speed of controller or Carrier
tool (controller communication speed default is 38400
baud)
4 - In event of defective communication with Carrier tool,
check that TS232/RS485 conver ter is capable of 38400
baud communication
5 - In event of defective communication with Carrier tool,
add line termination impedance over the bus then cancel
it after configuration.

IMPORTANT: The MAESTRO control system is a communication system with the ability to drive a large number of devices.
It is therefore advisable to pay special attention to all connections and the paths of the communication buses around the
system.
3.2.10 - Controller connections
IMPORTANT: A system is provided for maintaining and/or
locking out each electric cable that enters or leaves the
controller. This maintenance system depends on the terminal
unit delivered with the controller. It is described in the selection
and installation manual for each terminal unit.
3.2.10.1 - Controller power supply
The controller is powered from a single-phase mains network
at 230 VAC ( 10%) 50 Hz.
The recommended connection cable for the controller (J7) is
of the type: Earth - Neutral - Line 3 G 1.5 mm2.
It must meet the quality and installation standards of IEC
Recommendation 364 corresponding to Europe HD 384,
France NFC 15 100, UK IEE Wiring Regulation.

For wiring, see connection terminal diagram.

The maximum length of the connector cable is 30 metres.

Earth circuit connection (Earth):

The power supply cable enables the protection circuit to be
continuous. It must be connected to the terminal unit at the PE
terminal provided for the purpose.

Shielded electric heater safety command

The connection to J8 (shielded electric heater safety
command) is made at the factory. It consists of the following:
a female 2-pin MOLEX connector - Ref. 5264-2 (Order
Number Nb 50-37-5023)
a single pair 9/10 cable.

3.2.10.2 - Actuator output connections

The controller is delivered fully assembled, and connected to
the terminal unit control devices (valves, electric heater, fan
motor) through an appropriate electrical wiring bundle.

Temperature sensors
These sensors do not require special connectors (clip terminals).

3.2.10.3 - Input connections

Window/condensate drain pan contact - ON/OFF contact
Connection to the window/condensate drain pan contact input
(J2B) and to the ON/OFF contact input uses the following:
a female 2-pin WAGO connector - Ref. 231-102/026-000
a single pair 9/10 cable.
3.2.10.4 - Connecting the communication buses

Terminal block for the Zc controller

27

Secondary bus
The male connector (J9) is used to connect the controller to slave
controllers, to a Floor Manager or to a Building Management
System. The secondary bus (J9) is connected using a 3-pin
female WIELAND connector - Ref. 25 320 3353-0.

Local bus
The male connector (J5) is used to connect a Power Module.

The secondary bus connector is located at the extreme left of

the terminal block. It is a three-pin connector:
Pin 1: communication Pin 2: communication 0V
Pin 3: communication +

The local bus connector is located at the extreme left of the

terminal block. This is a five-pin connector:
Pin 1: communication Pin 2: communication 0V
Pin 3: communication +

The local bus (J5) is connected using a 5-pin female WIELAND

connector - Ref. 25 320 3553-0.

Zone Controller
Cable shielding to be
J5 local connected to terminal unit
side
bus
casing

Not supplied
by Carrier

Power Module side

local bus

Circuit diagram for Power Module to Zc controller

Zui bus
Pin 3: communication +
The controller is connected to the Zone User Interface (microPin 4: +10 V (user interface power supply)
terminal) using a male connector (J5). The Zui bus (J5) is
Pin 5: 0 V (user interface power supply)
connected using a 5-pin female WIELAND connector - Ref. 25
320 3553-0. This is a five-pin connector in which only pins 1,
A complete package containing all the connectors needed for
3, 4 and 5 are used:
installing the controller is available as an accessory. For specific
Pin 1: communication requirements please make direct contact with the supplier of
Pin 2: not used
this component.
Connectors supplied as accessories

Cable not supplied by Carrier

Zui terminal block side

Zone Controller
side

J5 local bus

Key:
Blanc = White
Bleu = Blue
Jaune = Yellow

Circuit diagram for the microterminal

28

Powering up the controller

NOTES: The voltage on the outputs for fan (J3), hot water
valve (J4A) and chilled water valve (J4B) is always the
same as the single-phase mains voltage (regardless of their
status) whenever they are not assigned a load (e.g. fan, valve
servomotor).
An operating controller or commands from the Zone User
Interface, Power Module, Floor Manager or master controller
(in the case of a slave controller) are used to power these
outputs up or down.
The voltage on the outputs for fan, hot water valve,
chilled water valve and additional heating is always the
same as the single-phase mains voltage if they are not
connected, regardless of the type of command received.
3.2.11 - Technical characteristics
3.2.11.1 - Electrical characteristics
The Zc controller takes its power from the low tension 230 VAC
mains supply.
Inputs

Power supply to the controller (J7) 230 VAC ( 10%) 16 A - 50 Hz

Setpoint reset when using the Carrier wall-mounted

thermostat (analogue input: J1 - T1) 0 to 100 kOhms

Water circuit temperature sensor for changeover function

(analogue input: J1 - T2) - 10 kOhms at 25C

Return air sensor or individual room temperature sensor or

room temperature sensor incorporated in the wall-mounted
thermostat (analogue input: J1 - T3) - 10 kOhms at 25C
Chilled water circuit entering temperature sensor for use
in subsequent application (analogue input: J1 - T4) - 10
kOhms at 25C
Remote on/off (Discrete input: J2A)
Window contact (Discrete input: J2B)
Electric heater safety fuse (Discrete input: J8)

NOTE: There is no input for Shielded Electric Heater Safety

Fuse (J8) on the Maestro controller for water applications.
Outputs

Variable speed fan (J3) 230 VAC ( 10%) - 1.1 A - 50 Hz

Chilled water valve (J4B) 230 VAC ( 10%) - 25 mA 50 Hz

Hot water valve (J4A) 230 VAC ( 10%) - 25 mA - 50 Hz

PTC electric heater (J6) 230 VAC ( 10%) - 16 A - 50 Hz

NOTE: There is no electric heater output (J6) on the Maestro
controller for water applications.
3.2.11.2 - Mechanical characteristics

Protection index of controller: IP 205

Operating environment: 0 to 50C at 30 to 90% relative

humidity (non-condensing)

Storage conditions: -40 to 85C at 30 to 95% relative

humidity (condensing)

Impacts during operation: Peaks of 5G in all planes and

all directions for 11 ms

Controller fastening method: Attached to terminal unit

with sheet metal screws.

4 holes 6

Dimensional drawing of controller

29

3.3 - The user interface (accessory)

Two user interfaces are available for connection to the controller:
the Zone User Interface (microterminal) and the wall-mounted
thermostat.
3.3.1 - The Zone User Interface
3.3.1.1 - Description
The Zone User Interface (microterminal) is the link between
the controller installed on the terminal unit and the user
occupying the air conditioned zone.
The Zone User Interface is fitted with a temperature sensor (10
kOhms) with which it measures the ambient temperature in the
air conditioned space.

Switching between Occupied and Unoccupied status;

Resetting the setpoint in the occupied status;
Selecting the fan speed and selecting air renewal mode.

The liquid crystal display unit allows the following to be

displayed:

A moving bar graph indicating the occupation status and

the setpoint reset relative to the value of the parameter;

The temperature of the air conditioned zone (definable by

parameter; default is Not Displayed);

The outside temperature (in conjunction with BMS only);

Fan status: automatic, 1, 2, 3 or air renewal;

Window status (if connected);

Mail waiting indicator (in conjunction with BMS only).

It can be connected:

either directly to the Maestro controller

or to the Power Module if there are lighting sources or

window blinds to be controlled.
A polarised double-pair connection is used for communication
(Zui bus). The power supply to the Zone User Interface is
provided by the controller or the Power Module.
The Zone User Interface can be installed on a desk-top or
placed in a wall-mounted holder (available as an accessory).
The wall-mounted holder is fixed to the wall by two screws not
supplied by Carrier. The microterminal is held in the holder by
two grips and a self-adhesive strip.
Choose the location of the microterminal carefully.
It is essential not to leave the microterminal in a draught or
close to a heat source (such as a lamp, computer, window,
direct sunlight, etc.) since these can have an adverse effect on
the ambient temperature reading.
If the Zone User Interface is connected directly to the controller,
only those functions related to air conditioning are accessible:

The Zone User Interface (microterminal)

Dimensional drawing of Zone User Interface

30

If a Power Module is incorporated in the system, the Zone

User Interface also allows control of the outputs available on
the Power Module in addition to the functions specifically
related to air conditioning:

Select required menu (Lights/Air conditioning/Controlled

output/Blinds);

Select lighting output to be actioned and On/Off command;

Select controlled output to be actioned and On/Off

command;
or

Lighting dimmer remote control (not supplied by Carrier)

on the controlled output (definable by parameter);

Select window blind to be actioned and Raise/Lower/

Angle command for window blinds (see chapter 3.4.8 Technical characteristics of the Power Module).
Master/slave architecture
Slave controllers and Power Modules do not necessarily have
to be connected to a Zone User Interface.
A Zone User Interface connected to a master Power Module
can have an effect on the following:

Control functions;

The lighting/controlled output/blind connected to the

Power Module concerned;

On an individual basis, the lighting/controlled output/blind

connected to three slave Power Modules defined as slave
No. 1, No. 2 and No. 3;

On a collective basis, the lighting/controlled outputs/blinds

belonging to the master Power Module and its slaves.

A Zone User Interface connected to a slave Power Module can

have an effect on the following:

Control functions;

The lighting/controlled output/blind connected to the slave

Power Module concerned;

The lighting/controlled outputs/blinds belonging to the

whole group of master and slave Power Modules.
The configuration parameters for the Zone User Interface are
stored in the controller in respect of parameters connected
with air conditioning and BMS data, and in the Power Module
in respect of parameters for controlling functions connected
with the lighting, controlled output and blinds.
NOTE: A detailed description of the Zone User Interface is
contained in a special user information sheet supplied with the
product.
3.3.1.2 - Zone User Interface connections
The Zone User Interface is supplied with three metres of doublepair connector cable fitted with a WAGO brand connector ref.
231-604.
A double-pair 9/10 cable + shielding is required to connect the
Zone User Interface to the Zc controller or Power Module.
The maximum length of the connector cable is 50 metres.
The connectors needed for making the link are:

Zone User Interface side: WAGO brand Ref. 231-104/

026-000

Zc controller side: WIELAND brand Ref. 25 320 3553-0

Power Module side: not required (fixed connector on

Power Module).

Connectors supplied as accessories

Cable not supplied by Carrier

Zui terminal block side

Zone Controller side

J5 local bus

Key:
Blanc = White
Bleu = Blue
Jaune = Yellow

Circuit diagram for Zone User Interface (microterminal) to controller

31

Connector supplied as accessory

Cable not supplied by Carrier

Zui terminal block side

Power Module side

Key:
Blanc = White
Bleu = Blue
Jaune = Yellow

Circuit diagram for Zone User Interface (microterminal) to Power Module

3.3.1.3 - Technical characteristics
Electrical characteristics

10 V DC very low voltage power supply from controller

or Power Module.
Mechanical characteristics

Dimensions: 135 x 67 x 27 mm

Colour of microterminal and wall holder: Pantone Blue

5467 U

Protection index: IP405

Operating environment: 0 to 50C at 30 to 90% relative

humidity (non-condensing)

Storage conditions: -40 to 70C at 30 to 95% relative

humidity (condensing)

Impacts during operation: Peaks of 5G in all planes and

all directions for 11 ms.

The following functions are available:

Switching between occupied and unoccupied status

Resetting the setpoint.

A light-emitting diode (LED) indicates the current occupation
status:
LED lit: Occupied
LED out: Unoccupied.

3.3.2 - Wall-mounted thermostat

3.3.2.1 - Description
The wall-mounted thermostat is the link between the controller
installed on the terminal unit and the user occupying the air
conditioned zone.
It is connected directly to the board on the controller (Zc).
It is fixed to the wall of the air conditioned zone. Choose the
location of the thermostat carefully.
It is recommended that the place chosen for the wall-mounted
thermostat should be representative of the temperature that
needs to be measured. It is important to avoid draughts and
exposure to direct sunlight.

32

Wall-mounted thermostat

Dimensional drawing of the wall-mounted thermostat

NOTE: A detailed description of the wall-mounted thermostat
is contained in a special user information sheet supplied with
the product.
3.3.2.2 - Wall-mounted thermostat connections
A triple-pair 9/10 cable + shielding is required to connect the
wall-mounted thermostat to the Zc controller.
Maximum length of connector cable: 30 metres.
The connectors needed for making the link are:

Wall-mounted thermostat side: not required (screw

terminals on thermostat)

Zc controller side: WIELAND brand Ref. 25 320 3553-0

3.3.2.3 - Technical characteristics

Electrical characteristics

10 V DC very low voltage power supply (for the LED)

from controller.
Mechanical characteristics

Dimensions: 80 x 80 x 44 mm

Colour: RAL 9010

Protection index: IP30

Operating environment: 0 to 50C at 10 to 90% relative

humidity (non-condensing)

Storage conditions: -10 to +70C

Maestro wall-mounted thermostat

Not supplied by Carrier

Wall-mounted thermostat terminal side

Zone Controller side

J5 local bus

J1 analogue inputs

The cable screening must be connected

to the terminal unit casing

Circuit diagram for wall-mounted thermostat to controller

33

3.4 - The Power Module

3.4.1 - The external Power Module

This optional module is used in applications which prefer to

use a Zone User Interface or BMS to control a lighting source
and/or to manage the power supply to a controlled output and/
or to raise/lower/angle a window blind.

3.4.1.1 - Outputs
The following apply to the external Power Module:

There are two power outlets capable of providing power

for office lighting. There are two duplicate outputs so that
several lighting sources can be connected if necessary.
The power supply for the lighting comes from the Power
Module.

There is another power outlet capable of providing power

for an additional lighting source, having either a remotely
controlled or conventional dimmer (see chapter 3.4.8.1 Electrical characteristics).

There is also a window blind command output (FRANCIAFLEX brand ) with a 24 VDC power supply.

It supports the following system functionalities:

Transmitting exchanges of information between the Zone

User Interface and its associated Zc controller

Transmitting window status to the associated controller

(if this facility is connected).
NOTE: The controlled output can take an additional lighting
source or lighting dimmer (an auxiliary module must be added
for the second of these) - Not supplied by Carrier.
There are two types of Power Module: the external Power
Module and the internal Power Module. The internal Power
Module cannot be used to control window blinds or deal with
window status.

3.4.1.2 - Inputs
An external Power Module can detect when a window is open,
as can the controller. The window status is transmitted to its
associated controller which then determines which operating
mode to apply.
The direction in which the window contact works can be
defined by parameter:

NO: Normally Open =>

Window closed: contact open
Window open: contact closed

NC: Normally Closed =>

Window closed: contact closed
Window open: contact open

Factory setting: Normally Open

Several windows can be connected to the same input.
In the case of NC logic, the contacts are to be cabled in series.
External Power Module

In the case of NO logic, the contacts are to be cabled in parallel.

Master/slave architecture and window contact:
If a Power Module detects a change of status in any of its
windows, it sends this information to its associated controller.
The operating mode then switches to defrost mode.
The controller stays in defrost mode until all windows have
returned to their initial status.

34

External Power Module - the terminal block

35

3.4.2 - The internal Power Module

3.4.2.1 - Outputs
The following apply to the internal Power Module:

There are two power outlets capable of providing power

for office lighting. There are two duplicate outputs so that
several lighting sources can be connected if necessary.
The power supply for the lighting comes from the Power
Module.

There is another power outlet capable of providing singlephase power for an additional lighting source, having
either a remotely controlled or conventional dimmer (see
chapter 3.4.8.1 - Electrical characteristics).
3.4.2.2 - Inputs
An internal Power Module has neither logical nor analogue
inputs.

3.4.3 - Communication buses

RS485 local bus (J7) - Carrier Comfort Network (CCN)

communication protocol enables a Power Module to be
connected to the associated controller.

RS485 Zui bus (J8) - Carrier Sensor Input/Output (SIO)

communication protocol enables a Zone User Interface
(microterminal) to be connected.
The local bus connector on the Power Module has three
pins:

Pin 1: signal
Pin 2: 0 V

Pin 3: signal +
The Zui bus connector on the Zone User Interface has four
pins:

Pin 1: signal +

Pin 2: 0 V

Pin 3: signal
Pin 4: VEE (positive (+) terminal of the user interface
power supply)

Internal Power Module - the terminal block

36

3.4.4 - Assigning parameters to Power Modules

3.4.4.1 - Parameter assignment software tool
There is just one software tool available: the Carrier MAESTRO
Configuration Tool.
This enables parameters to be assigned to Power Modules over
the local bus.

NOTE: Zone User Interfaces connected to slave Power

Modules cannot be used to control the individual outputs of
other Power Modules.
3.4.4.3 - Configuring the SERVICE parameters
Parameter

Description

Default
value

Light

0/1 (Absent/Present)
Declares the presence or absence of
lighting connected to the Power Module

3.4.4.2 - Configuring the SYSTEM parameters

Parameter

Description

Default value

Bus Number

1 to 128
This must be the same as the
address of the master controller to
which the Power Module is
attached (coding wheels)

Element Number

1 to 99
Bus element number (for
explanation see below)

Baud Rate

19200
Communication speed (not
modifiable)

19200

Priority

2
2
Communication protocol parameter
(not modifiable)

Software Part Number

16 characters
Software version (not modifiable)

Name

8 characters
Name of device (optional)

Description

24 characters
Description of device (optional)

Location

24 characters
Physical location of device
(optional)

CSA-SR-xxxxxx

Configuration of the Element Number parameter:

When it is connected to the master Power Module, the Zone User
Interface offers the possibility of individually controlling four
lighting sources, four controlled outputs and four window blinds.

Blind Move Up/Down

0/1 (Authorised/Not authorised)

Declares the presence of a window blind *
connected to the Power Module

Blind Inclination

0/1 (Authorised/Not authorised)

Declares the possibility of also
controlling the angle of a window blind

Socket Control

0/1/2
(Absence of any controlled output
connected to the Power Module.
/Presence of a controlled output
1
connected to the Power Module.
/Presence of a controlled output
connected to the Power Module and to a
remotely controlled dimmer.)

Zui Led On

0/1 (No/Yes)
Authorisation for back-lighting of the
translucent ON/OFF button on the Zone
User Interface

0/1/2/3
If the Power Module is the master, this
parameter represents the number of
slaves that the Zone User Interface
connected to it can control.
If the Power Module is a slave, this
parameter is 0.

Attached Slave

Window Contact

0/1
(Window contact Normally Open/Window 0
contact Normally Closed)

Window Icon For Purge 0/1 (No/Yes)

If YES, the Zone User Interface will
display the window icon continuously
(not flashing) on all accessible screens
during controller operating mode "Air
Renewal" (Purge).

3.4.4.4 - MAINTENANCE variables

Using the Element Number configuration parameter, the Power
Modules intended to be used for this purpose must be configured
to accept an individual command.
Master/Slave Configuration

Value of Element Number

parameter in power modulee

The Power Module is master

The Power Module is 1st slave

The Power Module is 2nd slave

The Power Module is 3rd slave

The Power Module is an additional slave

5 to 99

The effect of this is as follows:

The Power Module configured as 1st slave will execute

the Lighting/Controlled Output/Window Blind commands
from the Zone User Interface connected to the master
when icon 2 is selected from the selection window,

The Power Module configured as 2nd slave will

execute the Lighting/Controlled Output/Window Blind
commands from the Zone User Interface connected to the
master when icon 3 is selected from the selection
window,

The Power Module configured as 3rd slave will execute

the Lighting/Controlled Output/Window Blind commands
from the Zone User Interface connected to the master
when icon 4 is selected from the selection window.

Parameter

Description

Default
value

End Termination Line?

0/1 (No/Yes)
0
The "End Termination Line" variable is
read-only. It results from reading the
micro-switch located under the
transparent window on the terminal block.
If this micro-switch is in the ON position it
adds an impedance of 120 ohms on the
bus.

Rotary Element
Address

0 to 99
*
The "Power Module Address" variable is
read-only. This parameter corresponds to
the Power Module address given with the
aid of the two coding wheels that can be
seen through the transparent window on
the terminal block.

3.4.5 - Restarting a Power Module after a power failure

After a mains power cut, the Power Module restarts in such a
way that its lighting output(s) and controlled output are not
energised. The window blind output is powered with a 24 VDC
supply.

37

3.4.6 - Troubleshooting
The following table lists the main problems that may be met
and how they can be remedied:
Symptom

Remedy

Lighting output or controlled output

from Power Module not working

1 - Check the fuses on the power module.

Is the lighting or load capacity matched?

Window blind angle command not

working

1 - A window blind angle command from

the Zone User Interface is prohibited if
"ALL" is selected.
2 - Check the Power Module configuration.
3 - Check all connections.

Controller operation LED flashing

rapidly

1 - Faulty PROM

Controller operation LED not flashing

1 - Faulty board power supply

2 - Faulty board fuses

Zone User Interface not displaying

information

1 - Incorrect controller configuration; check

configuration of Local Bus Device type
parameter on controller local bus.
2 - Faulty Zui bus connections.
3 - Faulty microterminal power supply.

Zone User Interface mode is

Unoccupied but On/Off button for
switching to Occupied mode not
working

1 - Defective communication between

controller and Power Module; check
whether one or more devices are applying
a line termination impedance over the bus.

Window blind does not lower or stops

halfway

1 - Faulty window blind output

connections.
2 - Window blind problem.
3 - Faulty master Power Module controller
connections.

Defective communication with

controller

1 - Check connections.
2 - Check Power Module address.
3 - In event of defective communication
with Carrier tool, check that RS232/RS485
conver ter is capable of 19200 baud
communication.
4 - In event of defective communication
with Carrier tool, add line termination
impedance over the bus then cancel it
after configuration.

Blinds and lights operate at random

1 - Power up the controller so that it

acknowledges the messages from the
Power Module.
2 - Check Zc-Pm connections.

IMPORTANT: The Maestro control system is a communication

system with the ability to drive a large number of devices. It is
therefore advisable to pay special attention to all connections
and the paths of the communication buses around the system.
3.4.7 - Power Module connections
3.4.7.1 - Power Module power supply
The Power Module is energised from a single-phase mains
network at 230 VAC (10%) - 50 Hz.
The Power Module power supply (J1) must be connected with
the aid of the following items:
3 clips: STOCKO - Ref. RSB 7960 F 6,3-1/tinned brass
1 clip-holder: STOCKO - Ref. EH677
1 x 3-wire cable Earth - Neutral - Line G 1.5 mm2
The connection must meet the quality and installation standards
laid down in IEC Recommendation 364 corresponding to Europe
HD 384, France NFC 15 100 or UK IEE Wiring Regulation.
For wiring, see connection terminal diagram.
Protection circuit connection (Earth):
The power supply cable enables the protection circuit to be
continuous to the lighting output and controlled output
devices.
38

3.4.7.2 - Connections to input devices

Window contact
The window contact input (J2) must be connected using a
single-pair 9/10 cable.
The cable must be kept with the local bus and Zui bus
cables with the aid of a cable-grip.
No additional connectors are needed for the link (clip terminal).

3.4.7.3 - Connections to output devices

Lighting and Controlled outputs:
Each connection to lighting outputs (J4-J5) and the controlled
output (J6) uses the following items:
a male WAGO connector fitted with a strain-relieving
plate - Ref. 723-603/000-042/033-000
a cable-grip for a 3.7 mm2 aperture
a 3-wire cable Earth - Neutral - Line 1.5 mm2
Blinds output
The connection to the blinds output uses the following items:
a male WAGO connector fitted with a strain-relieving
plate - Ref. 231-604/033-000
a cable-grip for a 3.7 mm2 aperture
a double-pair 1.5 mm2 cable
Local bus
The connection to the local bus (J7) uses a 3-pin female
WIELAND connector - Ref. 253203353-0.
The cable must be kept with the window contact and Zui
bus cables with the aid of a cable-grip.
Zui bus
No additional connectors are needed for the link (clip terminal).
The cable must be kept with the window contact and local
bus cables with the aid of a cable-grip.
A complete package containing all the connectors needed for
installing a Power Module is available as an accessory. For
specific requirements please make direct contact with the
supplier of this component.

Zone Controller
side

J5 local
bus

Cable shielding to be
connected to terminal unit
casing

Not supplied
by Carrier

J7 local
bus

Power Module side

Circuit diagram for Power Module to Zc controller

Connectors supplied as accessories

Cable not supplied by Carrier

Zui terminal block side

Key:
Blanc = White
Bleu = Blue
Jaune = Yellow

Power Module side

Circuit diagram for Zone User Interface (microterminal) to Power Module

39

3.4.7.4 - Powering up a Power Module

The voltage on the outputs for lighting and controlled

output connected to the output devices is zero. A
lighting or controlled output command over the Zone
User Interface connected to the Power Module is used to
power these outputs up or down.

The voltage on the outputs for lighting and controlled

output that are not connected is always the same as the
single-phase mains voltage, regardless of the type of
command received.
3.4.8 - Technical characteristics
3.4.8.1 - Electrical characteristics
The Power Module takes its power from the single-phase 230
VAC (10%) 50 Hz mains supply.
Inputs

Power supply for the Power Module (J1) 230 VAC

(10%) - 2.8 A - 50 Hz

Window contact (discrete input: J2) (on external Power

Module)
Outputs

Lighting output (J4 - J5) 230 VAC (10%) - 1.3 A - 50 Hz 300 Watts resistive incandescent distributed over two
outputs.
(Qualified lighting: REGIANI 6416 non-compensated.
For any other type of lighting please contact Carrier as
distributors).

Controlled output (additional lighting) (J6) 230 VAC

(10%) - 1.3 A - 50 Hz - 300 Watts resistive incandescent.

(Qualified lighting: REGIANI 6416 non-compensated.

For any other type of lighting please contact Carrier as
distributors).
(Qualified lighting dimmer or remote control: NIKO
References: control unit C1 Ref. 65230
Dimmer interface Ref. 65330
System for dimmable HF electronic ballasts 1/10V. For any
other dimmer system please contact Carrier as distributors).
Blinds output (J3) 24 VDC (10%) - 200 mA on external
Power Module
(Qualified blind: FRANCIAFLEX. For any other type of
blind please contact Carrier as distributors).

3.4.8.2 - Mechanical characteristics

The recommended installation site for Power Modules is directly
in the air conditioned zone (e.g. false floor, false ceiling, hollow
partition), since this allows shorter cable lengths for lighting
and blinds. Installation zones must have natural ventilation to
allow the heat energy given off by Power Modules to disperse
correctly.
External and internal Power Modules have the same general
characteristics:

Protection index: IP 205

Protection index: IP 235 in test conditions with false-floor

slabs

Operating environment: 0 to 50C at 30 to 90% relative

humidity (non-condensing)

Storage conditions: -40 to 85C at 30 to 95% relative

humidity (condensing)

Impacts during operation: Peaks of 5G in all planes and

all directions for 11 ms

4 holes 6

Dimensional drawing of terminal blocks - internal and external Power Modules

40

3.5 - The Floor Manager (Fm)

A Floor Manager is an electronic card fitted with a display unit

and keypad giving local control over a group of controllers and
displaying the status of the terminal units connected to it.

All of these functions are accessible locally by using the builtin screen and keypad.

Acting as a communication gateway between the

controllers and a BMS.

It is connected to the secondary bus for controllers.

Its main functions are as follows:

Local supervision of the whole group of controllers

connected to the same secondary bus:
Displaying information
Changing parameters
Sending commands
Reading alarms

Creating and managing groups of controllers with the

same functions. For example:
A group containing all the controllers handling
conference rooms
In a multi-occupancy building, each group may
represent the controllers for a particular tenant

Associating automatic commands generated by

programmer units with particular groups (for example:
starting/stopping air conditioning at pre-defined times).

Floor Manager (Fm)

NOTE: A detailed description of the Floor Manager (Fm) is
contained in a special user information sheet supplied with the
product.

3.6 - Typical configurations

3.6.1 - Architecture with controller
Primary bus (optional)

Fm address 10

Secondary bus

Master Zc
address = 1

Slave Zc
address = 8

Master Zc
address = 3

Wall-mounted
thermostat

Zone 1
ZUI

Zone 2

ZUI

Key:
Fm
Floor Manager
Zc
Zone Controller
Pm
Power Module
Zui
Zone User Interface
(microterminal)

Zone 1
Zone 1 is air conditioned by two terminal units of the ICM
type (Individual Comfort Module). They are two-pipe systems
with changeover + additional PTC electric heater. The fan is
variable speed. A condensate drain pan level detector contact is
installed on the ICMs. Zone 1 is a conference room.

Zone 2
Zone 2 is air conditioned by one two-pipe terminal unit with
changeover + additional PTC electric heater. The fan is the
independent three-speed type. Zone 2 is an office.

41

3.6.1.1 - Assigning parameters to controllers

Configuring the Controller Setpoint parameters

Zone 1

Configuring the FACTORY parameters

Zone 1
Parameter
Fan Type

Zc (Address 1)
0 (variable
speed)

Zone 2
Zc (Address 8)
0 (variable
speed)

Parameter

Zc (Address 1)

Zone 2
Zc (Address 8)

Zc (Address 3)

Occupied Setpoint

21.0C

21.0C

21.0C

Occupied Dead Band

2.5C

2.5C

2.5C

1 (Three speed)

Unoccupied Setpoint

18.0C

18.0C

18.0C

4.0C

4.0C

4.0C

Zc (Address 3)

Cool Enable Duration

Unoccupied Dead Band

Heat Type

0 (None)

0 (None)

0 (None)

Frost Protect Setpoint

12.0C

12.0C

12.0C

0.2C

0.2C

0.2C

Heat Enable Duration

Setpoint Reset Step

Additional Heat Type

1 (PTC electric
heater)

1 (PTC electric
heater)

1 (PTC electric
heater)

Delta T CLWT Setpoint

12C

12C

12C

Delta T HLWT Setpoint

40C

40C

40C

CLWT Sensor Present

0 (No)

0 (No)

0 (No)

HLWT/CHG Sensor
Present

1 (Yes)

1 (Yes)

1 (Yes)

Window/Drain Pan
Type

2 (Condensate
drain pan
contact NO)

2 (Condensate
drain pan
contact NO)

0 (Window
contact NO)

Factory Test Info

8 ASCII
characters

8 ASCII
characters

8 ASCII
characters

Native Language

0 (English)

0 (English)

0 (English)

Configuring the SERVICE parameters

Zone 1

Zone 2

Parameter

Zc (Address 1)

Zc (Address 8)

Master Address

Local Bus Device Type

2 (Zone User
Interface)

2 (Zone User
Interface)

Zone 1

Zone 2

Parameter

Zc (Address 1)

Zc (Address 8)

Zc (Address 3)

Device Name

(optional)

(optional)

(optional)

Description

(optional)

(optional)

(optional)

Location

(optional)

(optional)

(optional)

Software Part Number

(not modifiable)

(not modifiable)

(not modifiable)

Model Number

(not modifiable)

(not modifiable)

(not modifiable)

Serial Number

(not modifiable)

(not modifiable)

(not modifiable)

Reference Number

(not modifiable)

(not modifiable)

(not modifiable)

Bus Number

10

10

10

1 (wall-mounted
thermostat)

Secondary Bus Com

Speed

38400 baud

38400 baud

38400 baud

Zc (Address 3)

Room Drying Select

0 (Never)

0 (Never)

0 (Never)

Loadshed Enabled

No

No

No

Control Temp Sensor

0 (Room
temperature sensor
in Zone User
Interface)

0 (Room
temperature
sensor in wallmounted
thermostat)

Control Sensor Bias

0.0C

0.0C

0.0C

Delta T Control Select

0 (No)

0 (No)

0 (No)

Changeover Enable

1 (Yes)

1 (Yes)

1 (Yes)

Threshold Temperature

18C

18C

18C

Enable Delay

10 min

10 min

10 min

Purge Duration

6 min

6 min

6 min

Cooling Minimum Speed

30%

30%

30%

Heating Minimum Speed

30%

30%

30%

Cooling Maximum Speed

90%

90%

90%

Heating Maximum Speed

70%

70%

70%

Proportional Gain
(variable fan speed)

7.0

7.0

7.0

Integral Gain (variable fan

speed)

0.7

0.7

0.7

Proportional Gain
(shielded electric heater)

6.0 (not significant)

6.0 (not significant)

6.0 (not
significant)

Integral Gain (shielded

electric heater)

0.6 (not significant)

0.6 (not significant)

0.6 (not
significant)

User Fan Control Enable

1 (Yes)

1 (Yes)

1 (Yes) (not
significant)

Zui Control Temp Icon

1 (Yes)

1 (Yes)

1 (Yes) (not
significant)

Zui OAT Icon

0 (No)

0 (No)

0 (No) (not
significant)

Zui Window Icon

1 (Yes)

1 (Yes)

1 (Yes) (not
significant)

42

Configuring the Identification and System parameters

Configuring the Alarm Management parameters

Zone 1

Zone 2

Parameter

Zc (Address 1)

Zc (Address 8)

Zc (Address 3)

Re-Alarm Time

15 min

15 min

15 min

Alarm Routing

1000 0000

1000 0000

1000 0000

Yes

Yes

Summary Alarm Enable Yes

Configuring the Timetable parameters

Zone 1

Zone 2

Parameter

Zc (Address 1)

Zc (Address 8)

Zc (Address 3)

Time

(11 :30)

(11 :30)

(11 :30)

Day of Week

(1) (Monday)

(1) (Monday)

(1) (Monday)

Holiday Today

Month

Day of Month

11

11

11

Year

99

99

99

3.6.2 - Architecture with controllers and Power Modules

Secondary bus

Master Zc
address = 1

Master Zc
address = 3

Slave Zc
address = 8

Local bus

Master Pm
address = 59

Slave Pm
address = 6

Master Pm
address = 5
Zui bus

Zui bus

Slave Pm
address = 54

ZUI

Key:
Fm
Zc
Pm
Zui

ZUI

Zone 2

Zone 1

ZUI

Floor Manager
Zone Controller
Power Module
Zone User Interface (microterminal)

Zone 1
Zone 1 is air conditioned by two terminal units of the ATM
type (Air Treatment Module). They are two-pipe systems
without changeover + PTC electric heater.

3.6.2.1 - Assigning parameters to controllers

Configuring the FACTORY parameters
Zone 1

Zone 2

The fan is variable speed.

Parameter

Zc (Address 1)

Zone 1 is an office. It has three opening windows with blinds.

Fan type

0
0
(variable speed) (variable
speed)

1
(three-speed)

Zone 2
Zone 2 is air conditioned by one two-pipe Fan Coil terminal
unit without changeover + shielded electric heater with return
air temperature sensor.

Cool Enable Duration

Heat Type

1 (PTC electric
heater)

1 (PTC electric
heater)

2 (shielded
electric heater)

The fan is three-speed.

Zone 2 is a conference room without windows.
Load shedding is authorised in both zone1 and zone 2:
Heating mode will be active and the electric heaters powered
only when the data for Loadshed In Effect is No (see chapter
3.2.3.9 - Load shedding).

Zc (Address 8) Zc (Address 3)

Heat Enable Duration

Additional Heat Type

0 (None)

0 (None)

0 (None)

CLWT Sensor Present

0 (No)

0 (No)

0 (No)

HLWT/CHG Sensor
Present

0 (No)

0 (No)

0 (No)

Window/Drain Pan Type 0 (window

contact NO)

0 (window
contact NO)

0 (window
contact NO)

Factory Test Info

8 ASCII
characters

8 ASCII
characters

8 ASCII
characters

Native Language

0 (English)

0 (English)

0 (English)

43

Configuring the SERVICE parameters

Zone 1

Configuring the Identification and System parameters

Zone 1

Zone 2

Zone 2

Parameter

Zc (Address 1)

Zc (Address 8)

Zc (Address 3)

Parameter

Zc (Address 1)

Zc (Address 8)

Zc (Address 3)

Master Address

Device Name

(optional)

(optional)

(optional)

Local Bus Device

Type

0 (Power Module) 1 (None)

0 (Power Module)

Description

(optional)

(optional)

(optional)

Room Drying Select

0 (Never)

0 (Never)

0 (Never)

Location

(optional)

(optional)

(optional)

Software Part Number

(not modifiable)

(not modifiable)

(not modifiable)

Model Number

(not modifiable)

(not modifiable)

(not modifiable)

Loadshed Enabled

Yes

Yes

Yes

Control Temp
Sensor

0 (Room
temperature
sensor in Zone
User Interface)

1 (Return air
temperature
sensor in terminal
unit)

Serial Number

(not modifiable)

(not modifiable)

(not modifiable)

Reference Number

(not modifiable)

(not modifiable)

(not modifiable)

Control Sensor Bias

0.0C

0.0C

0.0C

Bus Number

Delta T Control
Select

0 (No)

0 (No)

0 (No)

Secondary Bus Com

Speed

38400 baud

38400 baud

38400 baud

Changeover Enable

0 (No)

0 (No)

0 (No)

Threshold
Temperature

18C (not
significant)

18C (not
significant)

18C (not
significant)

Enable Delay

4 min (not
significant)

4 min (not
significant)

4 min (not
significant)

Purge Duration

6 min

6 min

6 min (not
significant)

Cooling Minimum
Speed

30%

30%

30% (not
significant)

Heating Minimum
Speed

30%

30%

30% (not
significant)

Cooling Maximum
Speed

90%

90%

90% (not
significant)

Heating Maximum
Speed

70%

70%

70% (not
significant)

Proportional Gain
(variable speed fan)

7.0

7.0

7.0 (not
significant)

Integral Gain
(variable speed fan)

0.7

0.7

0.7 (not
significant)

Proportional Gain
(shielded electric
heater)

6.0 (not
significant)

6.0 (not
significant)

6.0

Integral Gain
(shielded electric
heater)

0.6 (not
significant)

0.6 (not
significant)

0.6

User Fan Control

Enable

1 (Yes)

1 (Yes)

1 (Yes)

Zui Control Temp

Icon

1 (Yes)

1 (Yes)

1 (Yes)

Zui OAT Icon

0 (No)

0 (No)

0 (No)

Zui Window Icon

1 (Yes)

1 (Yes)

1 (Yes)

Configuring the Controller Setpoint parameters

Zone 1

Zone 2

Parameter

Zc (Address 1)

Zc (Address 8)

Zc (Address 3)

Occupied Setpoint

21.0C

21.0C

21.0C

Occupied Dead Band

2.5C

2.5C

2.5C

Unoccupied Setpoint

18.0C

18.0C

18.0C

Unoccupied Dead Band 4.0C

4.0C

4.0C

Frost Protect Setpoint

12.0C

12.0C

12.0C

Setpoint Reset Step

0.2C

0.2C

0.2C

Delta T CLWT Setpoint

12C

12C

12C

Delta T HLWT Setpoint

40C

40C

40C

44

Configuring the Alarm Management parameters

Zone 1

Zone 2

Parameter

Zc (Address 1)

Zc (Address 8)

Zc (Address 3)

Re-Alarm Time

0 min

0 min

0 min

Alarm Routing

No

No

Summary Alarm Enable No

Configuring the Timetable parameters

Zone 1

Zone 2

Parameter

Zc (Address 1)

Zc (Address 8)

Zc (Address 3)

Time

(11 :30)

(11 :30)

(11 :30

Day of Week

(1) (Monday)

(1) (Monday)

(1) (Monday)

Holiday Today

Month

Day of Month

11

11

11

Year

99

99

99

3.6.2.2 - Assigning parameters to Power Modules

Configuring the System parameters

Configuring the SERVICE parameters

Zone 1

Zone 2

Zone 1

Zone 2

Parameter

Pm 5

Pm 54

Pm 6

Pm 59

Parameter

Pm 5

Pm 54

Pm 6

Pm 59

Bus Number

Light

1 (Present)

1 (Present)

1 (Present)

1 (Present)

Element
Number

Blind Move
Up/Down

1 (Authorised) 1 (Authorised) 1 (Authorised)

0 (Not
authorised)

Baud Rate

19200 (not
modifiable)

19200 (not
modifiable)

19200 (not
modifiable)

19200 (not
modifiable)

Blind
Inclination

1 (Authorised) 1 (Authorised) 1 (Authorised)

0 (Not
authorised)

Priority

2 (not
modifiable)

2 (not
modifiable)

2 (not
modifiable)

2 (not
modifiable)

Socket Control 0 (Absent)

0 (Absent)

0 (Absent)

0 (Absent)

Zui Led On

1 (Yes)

1 (Yes)

1 (Yes)

Attached Slave 2

1 (Yes)

Software Part 16 characters

Number
(not
modifiable)

16 characters
(not
modifiable)

16 characters
(not
modifiable)

16 characters
(not
modifiable)

Name

(optional)

(optional)

(optional)

(optional)

Window
Contact

1 (Window
contact NC)

1 (Window
contact NC)

1 (Window
contact NC)

0 (Window
contact NO)

Description

(optional)

(optional)

(optional)

(optional)

1 (Yes)

1 (Yes)

1 (Yes)

Location

(optional)

(optional)

(optional)

(optional)

Window Icon
For Purge

0 (Not
significant)

45

46

47

Order No. 18117-76, 1999 09 . Supersedes order No. 1998 07

The manufacturer reserves the right to change any product specification without notice.

Manufactured by Carrier SA, Montluel, France

Printed in France
Printed on totally chlorine-free paper