ZS 75

APF185878

Instruction book
Atlas Copco

ZS 75
APF185878

Instruction book
Original instructions

Copyright Notice
Any unauthorized use or copying of the contents or any part thereof is prohibited.
This applies in particular to trademarks, model denominations, part numbers and drawings.

This instruction book is valid for CE as well as non-CE labelled machines. It meets the
requirements for instructions specified by the applicable European directives as identified
in the Declaration of Conformity.

2013 - 08

www.atlascopco.com
 Instruction book

Table of contents

1 Safety precautions..........................................................................................................4

1.1 SAFETY ICONS...................................................................................................................................4

1.2 SAFETY PRECAUTIONS, GENERAL...........................................................................................................4

1.3 SAFETY PRECAUTIONS DURING INSTALLATION...........................................................................................5

1.4 SAFETY PRECAUTIONS DURING OPERATION..............................................................................................6

1.5 SAFETY PRECAUTIONS DURING MAINTENANCE OR REPAIR...........................................................................7

2 General description........................................................................................................9

2.1 INTRODUCTION...................................................................................................................................9

2.2 REGULATION...................................................................................................................................11

2.3 FLOW DIAGRAM AND COOLING SYSTEM..................................................................................................15

3 Installation.....................................................................................................................19

3.1 DIMENSION DRAWING........................................................................................................................19

3.2 INSTALLATION PROPOSAL...................................................................................................................21

3.3 SERVICE DIAGRAM............................................................................................................................22

3.4 OIL COOLER FAN INSTALLATION...........................................................................................................24

3.5 ELECTRIC CABLE SIZE.......................................................................................................................26

3.6 QUALITY OF SAFETY COMPONENTS.......................................................................................................30

3.7 PROTECTION OF ELECTRICAL EQUIPMENT..............................................................................................30

3.8 GENERAL PICTOGRAPHS....................................................................................................................34

4 Minimum requirements for safe regulation................................................................35

5 Operating instructions.................................................................................................46

5.1 INITIAL START-UP..............................................................................................................................46

5.2 BEFORE STARTING............................................................................................................................47

5.3 TAKING OUT OF OPERATION................................................................................................................48

2 APF185878
Instruction book

6 Maintenance..................................................................................................................49

6.1 PREVENTIVE MAINTENANCE SCHEDULE..................................................................................................49

6.2 MOTOR GREASING............................................................................................................................50

6.3 OIL SPECIFICATIONS..........................................................................................................................50

7 Servicing procedures...................................................................................................51

7.1 AIR FILTER......................................................................................................................................51

7.2 OIL AND OIL FILTER CHANGE...............................................................................................................53

7.3 DISPOSAL OF USED MATERIAL.............................................................................................................53

8 Problem solving............................................................................................................54

8.1 PROBLEM SOLVING...........................................................................................................................54

9 Technical data...............................................................................................................55

9.1 READINGS.......................................................................................................................................55

9.2 REFERENCE CONDITIONS AND LIMITATIONS............................................................................................55

9.3 BLOWER DATA.................................................................................................................................56

9.4 NOISE LEVEL DATA...........................................................................................................................56

10 Pressure equipment directives...................................................................................57

APF185878 3
 Instruction book

1 Safety precautions

1.1 Safety icons

Explanation

Danger for life

Warning

Important note

1.2 Safety precautions, general

General precautions
1. The operator must employ safe working practices and observe all related work safety requirements and
regulations.
2. If any of the following statements does not comply with the applicable legislation, the stricter of the two
shall apply.
3. Installation, operation, maintenance and repair work must only be performed by authorized, trained,
specialized personnel.
4. The compressor is not considered capable of producing air of breathing quality. For air of breathing quality,
the compressed air must be adequately purified according to the applicable legislation and standards.
5. Before any maintenance, repair work, adjustment or any other non-routine checks, stop the compressor,
press the emergency stop button, switch off the voltage and depressurize the compressor. In addition, the
power isolating switch must be opened and locked.
On units powered by a frequency converter, wait 10 minutes before starting any electrical repair.

If the machine is equipped with an automatic restart after voltage failure function and if this
function is active, be aware that the machine will restart automatically when the power is
restored if it was running when the power was interrupted!

6. Never play with compressed air. Do not apply the air to your skin or direct an air stream at people. Never
use the air to clean dirt from your clothes. When using the air to clean equipment, do so with extreme
caution and wear eye protection.
7. The owner is responsible for maintaining the unit in safe operating condition. Parts and accessories shall
be replaced if unsuitable for safe operation.
8. It is prohibited to walk or stand on the unit or on its components.

4 APF185878
Instruction book

1.3 Safety precautions during installation

All responsibility for any damage or injury resulting from neglecting these precautions, or
non observance of the normal caution and care required for installation, operation,
maintenance and repair, even if not expressly stated, will be disclaimed by the
manufacturer.

Precautions during installation

1. The machine must only be lifted using suitable equipment in accordance with the applicable safety
regulations. Loose or pivoting parts must be securely fastened before lifting. It is strictly forbidden to
dwell or stay in the risk zone under a lifted load. Lifting acceleration and deceleration must be kept within
safe limits. Wear a safety helmet when working in the area of overhead or lifting equipment.
2. The unit is designed for indoor use. If the unit is installed outdoors, special precautions must be taken;
consult your supplier.
3. In case the device is a compressor, place the machine where the ambient air is as cool and clean as possible.
If necessary, install a suction duct. Never obstruct the air inlet. Care must be taken to minimize the entry
of moisture at the inlet air.
4. Any blanking flanges, plugs, caps and desiccant bags must be removed before connecting the pipes.
5. Air hoses must be of correct size and suitable for the working pressure. Never use frayed, damaged or
worn hoses. Distribution pipes and connections must be of the correct size and suitable for the working
pressure.
6. In case the device is a compressor, the aspirated air must be free of flammable fumes, vapors and particles,
e.g. paint solvents, that can lead to internal fire or explosion.
7. In case the device is a compressor, arrange the air intake so that loose clothing worn by people cannot be
drawn in.
8. Ensure that the discharge pipe from the compressor to the aftercooler or air net is free to expand under
heat and that it is not in contact with or close to flammable materials.
9. No external force may be exerted on the air outlet valve; the connected pipe must be free of strain.
10. If remote control is installed, the machine must bear a clear sign stating: DANGER: This machine is
remotely controlled and may start without warning.
The operator has to make sure that the machine is stopped and depressurized and that the electrical isolating
switch is open, locked and labelled with a temporary warning before any maintenance or repair. As a
further safeguard, persons switching on or off remotely controlled machines shall take adequate
precautions to ensure that there is no one checking or working on the machine. To this end, a suitable
notice shall be affixed to the start equipment.
11. Air-cooled machines must be installed in such a way that an adequate flow of cooling air is available and
that the exhausted air does not recirculate to the compressor air inlet or cooling air inlet.
12. The electrical connections must correspond to the applicable codes. The machines must be earthed and
protected against short circuits by fuses in all phases. A lockable power isolating switch must be installed
near the compressor.
13. On machines with automatic start/stop system or if the automatic restart function after voltage failure is
activated, a sign stating "This machine may start without warning" must be affixed near the instrument
panel.
14. In multiple compressor systems, manual valves must be installed to isolate each compressor. Non-return
valves (check valves) must not be relied upon for isolating pressure systems.
15. Never remove or tamper with the safety devices, guards or insulation fitted on the machine. Every pressure
vessel or auxiliary installed outside the machine to contain air above atmospheric pressure must be
protected by a pressure relieving device or devices as required.

APF185878 5
 Instruction book

16. Piping or other parts with a temperature in excess of 70˚C (158˚F) and which may be accidentally touched
by personnel in normal operation must be guarded or insulated. Other high temperature piping must be
clearly marked.
17. For water-cooled machines, the cooling water system installed outside the machine has to be protected by
a safety device with set pressure according to the maximum cooling water inlet pressure.
18. If the ground is not level or can be subject to variable inclination, consult the manufacturer.
19. If the device is a dryer and no free extinguishing system is present in the air net close to the dryer, safety
valves must be installed in the vessels of the dryer.

Also consult following safety precautions: Safety precautions during operation and Safety
precautions during maintenance.
These precautions apply to machinery processing or consuming air or inert gas.
Processing of any other gas requires additional safety precautions typical to the application
which are not included herein.
Some precautions are general and cover several machine types and equipment; hence
some statements may not apply to your machine.

1.4 Safety precautions during operation

All responsibility for any damage or injury resulting from neglecting these precautions, or
non observance of the normal caution and care required for installation, operation,
maintenance and repair, even if not expressly stated, will be disclaimed by the
manufacturer.

Precautions during operation

1. Never touch any piping or components of the compressor during operation.
2. Use only the correct type and size of hose end fittings and connections. When blowing through a hose or
air line, ensure that the open end is held securely. A free end will whip and may cause injury. Make sure
that a hose is fully depressurized before disconnecting it.
3. Persons switching on remotely controlled machines shall take adequate precautions to ensure that there
is no one checking or working on the machine. To this end, a suitable notice shall be affixed to the remote
start equipment.
4. Never operate the machine when there is a possibility of taking in flammable or toxic fumes, vapors or
particles.
5. Never operate the machine below or in excess of its limit ratings.
6. Keep all bodywork doors shut during operation. The doors may be opened for short periods only, e.g. to
carry out routine checks. Wear ear protectors when opening a door.
On compressors without bodywork, wear ear protection in the vicinity of the machine.
7. People staying in environments or rooms where the sound pressure level reaches or exceeds 80 dB(A)
shall wear ear protectors.
8. Periodically check that:
• All guards are in place and securely fastened
• All hoses and/or pipes inside the machine are in good condition, secure and not rubbing
• No leaks occur
• All fasteners are tight
• All electrical leads are secure and in good order
• Safety valves and other pressure relief devices are not obstructed by dirt or paint
• Air outlet valve and air net, i.e. pipes, couplings, manifolds, valves, hoses, etc. are in good repair, free
of wear or abuse

6 APF185878
Instruction book

• Air cooling filters of the electrical cabinet are not clogged

9. If warm cooling air from compressors is used in air heating systems, e.g. to warm up a workroom, take
precautions against air pollution and possible contamination of the breathing air.
10. On water-cooled compressors using open circuit cooling towers, protective measures must be taken to
avoid the growth of harmful bacteria such as Legionella pneumophila bacteria.
11. Do not remove any of, or tamper with, the sound-damping material.
12. Never remove or tamper with the safety devices, guards or insulations fitted on the machine. Every pressure
vessel or auxiliary installed outside the machine to contain air above atmospheric pressure shall be
protected by a pressure relieving device or devices as required.
13. Yearly inspect the air receiver. Minimum wall thickness as specified in the instruction book must be
respected. Local regulations remain applicable if they are more strict.

Also consult following safety precautions: Safety precautions during installation and Safety
precautions during maintenance.
These precautions apply to machinery processing or consuming air or inert gas.
Processing of any other gas requires additional safety precautions typical to the application
which are not included herein.
Some precautions are general and cover several machine types and equipment; hence
some statements may not apply to your machine.

1.5 Safety precautions during maintenance or repair

All responsibility for any damage or injury resulting from neglecting these precautions, or
non-observance of the normal caution and care required for installation, operation,
maintenance and repair, even if not expressly stated, will be disclaimed by the
manufacturer.

Precautions during maintenance or repair

1. Always use the correct safety equipment (such as safety glasses, gloves, safety shoes, etc.).
2. Use only the correct tools for maintenance and repair work.
3. Use only genuine spare parts.
4. All maintenance work shall only be undertaken when the machine has cooled down.
5. A warning sign bearing a legend such as "work in progress; do not start" shall be attached to the starting
equipment.
6. Persons switching on remotely controlled machines shall take adequate precautions to ensure that there
is no one checking or working on the machine. To this end, a suitable notice shall be affixed to the remote
start equipment.
7. Close the compressor air outlet valve before connecting or disconnecting a pipe.
8. Before removing any pressurized component, effectively isolate the machine from all sources of pressure
and relieve the entire system of pressure.
9. Never use flammable solvents or carbon tetrachloride for cleaning parts. Take safety precautions against
toxic vapours of cleaning liquids.
10. Scrupulously observe cleanliness during maintenance and repair. Keep dirt away by covering the parts
and exposed openings with a clean cloth, paper or tape.
11. Never weld or perform any operation involving heat near the oil system. Oil tanks must be completely
purged, e.g. by steam-cleaning, before carrying out such operations. Never weld on, or in any way modify,
pressure vessels.

APF185878 7
 Instruction book

12. Whenever there is an indication or any suspicion that an internal part of a machine is overheated, the
machine shall be stopped but no inspection covers shall be opened before sufficient cooling time has
elapsed; this to avoid the risk of spontaneous ignition of the oil vapour when air is admitted.
13. Never use a light source with open flame for inspecting the interior of a machine, pressure vessel, etc.
14. Make sure that no tools, loose parts or rags are left in or on the machine.
15. All regulating and safety devices shall be maintained with due care to ensure that they function properly.
They may not be put out of action.
16. Before clearing the machine for use after maintenance or overhaul, check that operating pressures,
temperatures and time settings are correct. Check that all control and shut-down devices are fitted and that
they function correctly. If removed, check that the coupling guard of the compressor drive shaft has been
reinstalled.
17. Every time the separator element is renewed, examine the discharge pipe and the inside of the oil separator
vessel for carbon deposits; if excessive, the deposits should be removed.
18. Protect the motor, air filter, electrical and regulating components, etc. to prevent moisture from entering
them, e.g. when steam-cleaning.
19. Make sure that all sound-damping material and vibration dampers, e.g. damping material on the bodywork
and in the air inlet and outlet systems of the compressor, is in good condition. If damaged, replace it by
genuine material from the manufacturer to prevent the sound pressure level from increasing.
20. Never use caustic solvents which can damage materials of the air net, e.g. polycarbonate bowls.

Also consult following safety precautions: Safety precautions during installation and Safety
precautions during operation.
These precautions apply to machinery processing or consuming air or inert gas.
Processing of any other gas requires additional safety precautions typical to the application
which are not included herein.
Some precautions are general and cover several machine types and equipment; hence
some statements may not apply to your machine.

8 APF185878
Instruction book

2 General description

2.1 Introduction

General views

General view, ZS Standard

APF185878 9
 Instruction book

Front view, ZS Basic

Rear view, ZS Basic

10 APF185878
Instruction book

Ref. Name
AF Air filter
AO Air outlet
Co Oil cooler
CV Check valve
E Blower element
M1 Blower motor
M2 Motor, oil pump
OF Oil filter
OP Oil pump
PD Pulsation damper
SG Oil level sight glass
ST/BLV Start valve/blow-off valve
1 Vibration dampers

ZS are air-cooled, low-pressure, single-stage, electric motor-driven screw blowers which deliver oil-free,
pulsation-free air.
The blowers can be provided with an optional sound-insulated bodywork.
The blowers include mainly:
• Air filter
• Blower element
• Check valve
• Pulsation damper
• Drive coupling
• Motor
• Gear casing
• Start-up valve
• Oil cooler with cooler fan
• Frame

2.2 Regulation

Valve description
The start-up / safety valve combination is an assembly of a main valve and a pilot valve. The maximum
pressure is pre-set and cannot be manipulated or adjusted (sealed). In case of damage or wrong valve settings,
the complete valve assembly has to be replaced by Atlas Copco.

APF185878 11
 Instruction book

Main valve

The blow-off valve is mounted on the flanged opening on the pipe of the blower outlet. The inlet opening and
valve seat are located in the bottom base (1). The main valve is formed by the rubber bellows (2), which is
fixed to the top base (3). The top base is firmly connected to the bottom base (1) by guide rods (4). Pressure
is fed from the inlet opening to the control valve (5) by the tube (6). The movable base (7) fixed to the bottom
of the bellows (2), moves on guide rods (4) and forms the main valve disc. The inner area of the bellows (2)
is connected to the control valve (5). When getting pressurized with process air, the movable base (7) seals
off the valve seat. The pressure in the bellows (2) is relieved by releasing the air in the control valve (5).

12 APF185878
Instruction book

Control valve

The control valve is opened and closed by a pin (8) pushing on a ball (9) which is positioned by a spring (10).
The spring force is regulated by a setting screw (11). Chamber (U) is pressurized by a tube connection to
chamber (X). Through the opening to the main valve the bellows (2) is pressurized. If the pressure in chamber
(X) increases the spring force (set maximum pressure), the membrane (13) acts on the pin (8) to move the
ball (9). Pressurized air is released along the pin (8) into chamber (V) which is open to the ambient atmosphere.

Valve function
The valve has two functions:
• Starting valve function:
while the blower is starting, the valve ensures gradual pressure and torque increase.
• Safety valve function:
while the blower is in operation, the valve protects the blower from overload (pressure increase above the
permissible limit).
Starting valve function:

APF185878 13
 Instruction book

In the state without pressure, the main valve is open. The bottom base is held by the springs.

While the blower is starting, some pressure is generated in the space between the seat and the movable base.
The pressure is then transported into the compensator through the control valve.
As the surface of the bottom of the compensator is larger than the seat surface and thus the force is higher,
the metal compensator will close within a few seconds due to the gradual pressure increase.
This will result in starting the blower with continuous load rise. The metal compensator must press the springs,
which ensure that the valve is open while it is not under load.
If the valve was not open in the unloaded state, it would not be able to perform the starting valve function.
By removing the springs, the starting valve function can be disengaged or eliminated.

Safety valve function

While the blower is in normal operation, i.e. after start-up, the main valve disc is closed and the pressure in
the control valve is on both sides of its cone (small ball). The force generated by pressure against the
membrane, the surface of which is larger than the surface of the small ball contacting in the seat, is smaller
than the total forces generated by the spring and by pressure against the small ball surface in the seat. The
control valve is closed.

14 APF185878
Instruction book

If the pressure exceeds the set limit, this is when the force generated by pressure against the annulus (the
membrane surface minus the surface of the small ball contact) is higher than the force generated by the spring,
the small ball will lift and release gas under pressure into the atmosphere.
The pressure in the metal compensator will then drop and the main valve will open.
Due to the pressure drop, the control valve will close (and the release of gas into the atmosphere will stop).
The pressure in the metal compensator will rise again and the main valve will close again.

2.3 Flow diagram and cooling system

Flow diagram

Text on figure:

(1) Air outlet

(2) Customer's installation
(3) Atlas Copco's installation
(4) To atmosphere
(5) Blow off
(6) Customer's installation
(7) Only ZS 18-30
(8) Air inlet
(9) Only ZS 7-75

APF185878 15
 Instruction book

(10) Only ZS 7-22 VSD

Component list

100 Air inlet filter process air

101 Expansion joint
102 Inlet silencer
104 Oil-free air compressor stage
105 Air outlet silencer
106 Compensator
107 Control valve (optional)
108 Start-up / blow-off valve
109 Expansion joint
110 Valve assembly
115 Check valve
130 Oil sump
131 Oil pump + motor
134 By-pass valve (integrated in oil pump)
133 Oil filter
132 Oil cooler
150 Drive motor
135 Fan + motor
136 Oil manifold
160 Electrical cubicle
169 Oil sump breather with filter

Air flow
Air drawn through filter (100) is compressed in blower element (104) and discharged through check valve
(115) towards the air net.

16 APF185878
Instruction book

Oil system

The oil system may only be pressurized if the blower is in operation.

APF185878 17
 Instruction book

To guarantee an optimum operation of the blower, proper lubrication of bearings and gears is necessary. After
switching on the power to the motor (M2) oil is sucked in from the oil tank by oil pump (OP). The oil flows
through cooler (Co) and oil filter (OF) to the oil manifold (136). From the oil manifold the oil is distributed
to the gears and bearings. The gears are lubricated by means of a nozzle (1.5 mm / 0.059 in).
On ZS 37 up to ZS 75, after lubricating the bearing at the drive end side, the oil is returned to the oil tank.
The optimum oil pressure is 2.5 bar (36.26 psi). The blower must be protected against low oil pressure and
high oil temperature by the customer. See section Minimum requirements for safe regulation. The oil pump
is provided with a pressure relief valve to protect the oil system in case of overpressure.
The oil system includes a pressure switch to stop the blower immediately if the oil pressure should drop below
2 bar (29 psi).
The oil tank is provided with an oil level sight glass (SG) to check the oil level, and a breather to neutralize
oil vapor generated by the heated oil.
The oil cooler is cooled by a fan which must be connected locally. (See section Oil cooler fan installation).
Check the rotation direction of the fan: air must be drawn in from the outside of the blower and blown through
the cooler.

Cooling system
The blowers are provided with an air-cooled oil cooler (132), the cooling air is generated by an electric motor
driven fan.

18 APF185878
Instruction book

3 Installation

3.1 Dimension drawing

Dimensions

Dimensions for ZS 37, ZS 55 and ZS 75 Standard

APF185878 19
 Instruction book

Text on figure

Reference Name
(1) Electrical cable passage
(2) Center of gravity
(3) Compressor air inlet
(4) Compressor cooling air outlet
(5) View-A
(6) View-A
(8) Cooling air inlet oil cooler
(9) Compressor cooling air inlet
(10) Compressed air outlet
(11) Mass
(12) Compressor air outlet
(13) View-B

20 APF185878
Instruction book

3.2 Installation proposal

Blower room example

ZS 37, ZS 55 and ZS 75 Standard

Text on figure

Reference Name
(1) Compressed air inlet
(2) Compressor cooling air outlet
(3) Cooling air inlet, oil cooler
(4) Compressor cooling air inlet
(5) Compressed air outlet
(6) Top view

APF185878 21
 Instruction book

Reference Name
(7) Ventilation flow

Warning

The maximum pressure allowed on the blower from the air net is 1.3 bar (18.9 psi).

Thermal insulation should be provided to protect against the high temperature of the air outlet
valve and air delivery pipe.

Installation guidelines
1. Install the blower on a level floor suitable for taking its weight.
The minimum distance between the top of the unit and the ceiling is 1200 mm (47 in).
Distances between units and walls stated are minimum.
2. Calculate the maximum pressure drop over the delivery pipe as follows in bar:
dp = (L x 450 x Qc1.85) / (d5 x P)
dp = pressure drop (recommended maximum = 0.1 bar)
L = length of delivery pipe in m
d = inner diameter of the delivery pipe in mm
P = absolute pressure at the blower outlet in bar(a)
Qc = free air delivery of the blower in l/s
3. Avoid recirculation and intake of hot air in compressed air inlet grating
4. Electrical power supply entry

Prevention of noise radiation caused by resonance of the discharge pipe

• Wall thickness of the pipe to be considered.
• Acoustic insulation of the discharge pipe is recommended.
• The anchoring method needs to decouple pipe resonance from the building.
• Be advised on the air velocity in the discharge pipe to prevent noise radiation due to resonance.

3.3 Service diagram

Star-delta connection

Only the part with the electrical connection is shown below; a complete service diagram is
delivered loose with the blower.

22 APF185878
Instruction book

Electrical connections ZS 7 up to ZS 75

Fan motor connections ZS 7 up to ZS 75

APF185878 23
 Instruction book

Text on figures

(1) With 6 fuses Type 1 or Type 2

(2) With 6 fuses Type 1 or Type 2
(3) Customer's installation
(4) Main drive motor
(5) Star connection

Component list

Reference Description
F1 Fuse
F2 Fuse
F3 Fuse
F4 Fuse
F5 Fuse
F6 Fuse
F10 Fuse
F11 Fuse
F12 Fuse
F15 Overload relay
F21 Overload relay
K15 Control relay
K21 Line contactor
K22 Star contactor
K23 Delta contactor
K25 Phase sequence protection
M1 Main drive motor
M2 Pump motor
T1 Transformer

3.4 Oil cooler fan installation

Instruction
The electrical connection of the oil cooler fan depends on the supply voltage.
Check that the fan is rotating in the correct direction as shown by the symbol below!

24 APF185878
Instruction book

115V/60Hz

230V/50Hz

Text on figure:

1 Blue
2 Yellow/Green
3 Black

APF185878 25
 Instruction book

4 Brown
5 Top
6 Front view

3.5 Electric cable size

General

• The voltage on the motor terminals must not deviate more than 10% of the nominal
voltage.
It is however highly recommended to keep the voltage drop over the supply cables at
nominal current below 5% of the nominal voltage (IEC 60204-1). If cables are grouped
together with other power cables, it may be necessary to use cables of a larger size than
those calculated for the standard operating conditions.
• Use the original cable entry. See section Dimension drawings.
To preserve the protection degree of the electric cubicle and to protect its
components from dust from the environment, it is mandatory to use a proper cable
gland when connecting the supply cable to the blower.
• Local regulations remain applicable if they are stricter than the values proposed below.
• All electrical components should be earthed; also the frame should be earthed at the
foreseen earthing point. All earthing points must be on the same potential.
• When there are sharp edges they shall be removed.
• When necessary use cable glands and conduits for cable protection.

Control wiring/ sensor wiring

• The cables shall be built according to IEC60332-1
• All wires shall be built according to IEC60288 CI.5
• The required nominal voltage is HAR300/500V or for CSA/UL 600V for control cable/wires.
• The required nominal voltage is HAR 300/300V and for CSA/UL 300V for sensor wiring.
• All earthing cables should be green/yellow.
• The cables must be calculated according to the regulations.
• When the cable is installed it can not touch any hot components like: element, piping, silencer,…
• The sensor wiring has to be screened and there must be a minimum distance of 10cm/ 4 inch between the
main motor wiring and the sensor cables.
• The minimum temperature design of the cable shall be 70°C.

Motor wiring/unit wiring

The motor cable must be installed in a conduit. If a VSD drive controls the motor the conduit shall be of metal.
The conduit must be oil resistant.
IEC versions
For IEC designed control panels, the below suggested cable sections are calculated according to IEC
60364-5-52 electrical installations of buildings, part 5: selection and erection equipment, section 52: current-
carrying capacities in wiring systems.
Standard conditions refer to loose copper conductors or multi-core cable with 70˚C PVC insulation in free
air or on open cable trays (installation method C) at 30˚C ambient temperature and operating at nominal
voltage. The cables may not be grouped with other power circuits or cables.

26 APF185878
Instruction book

Worst case conditions refer to:

• ambient temperature > 30˚C (86 ˚F)
• cables in closed raceway, conduit or trunking system (installation method B2) at 40 ˚C ambient temperature
• cables not grouped with other cables

Fuse calculations for IEC are done according to IEC 60364-4-43 electrical installations of buildings, part
4: protection for safety- section 43: protection against overcurrent. Fuse sizes are calculated in order to protect
the cable against short circuit. Fuse type aM is recommended but gG/gL is also allowed.
CSA/UL versions
For UL designed industrial control panels, calculations for cable sections and fuses are done according to
UL508a (Industrial control panels).
For CSA, calculations for cable sections and fuses are done according to CSA 22.2 (Canadian electrical
code).
Standard conditions: maximum 3 copper conductors in raceway or cable with 85-90˚C (185-194 ˚F)
insulation at ambient temperature 30 ˚C (86 ˚F), operating at nominal voltage; cables not grouped with other
cables.
Worst case conditions: ambient temperature > 30 ˚C (86 ˚F), maximum 3 copper conductors in raceway or
cable with 85-90 ˚C (185-194 ˚F) insulation at 46 ˚C (115 ˚F) ambient temperature and operating at nominal
voltage. Cables not grouped with other cables.
Fuse size is the maximum fuse size in order to protect the motor against short circuit. For CSA fuse HRC
form II, for UL fuse class RK5.
If the local conditions are more severe than the described standard conditions, the cables and fuses for worst
case conditions should be used.

Maximum allowed fuse ratings

Cable size (mm2) Maximum fuse (A)

6 40
10 50
16 63
25 80
35 100
50 125

APF185878 27
 Instruction book

Cable size (mm2) Maximum fuse (A)

70 160
95 175
120 200

Motor installation
Make sure that the interior components of the terminal box (such as the terminal board and cable connections)
are not damaged. Foreign bodies, dirt and moisture must not be allowed to get into the terminal box. For
information on entries into the terminal box, please refer to DIN 42925. Any other open entries must be sealed
with O-rings or suitable flat gaskets to prevent dust and water from entering, while the terminal box itself
must be sealed against dust and water using the original seal.
Please observe the tightening torques for cable glands and other screws.
Knockout openings
• Knockout openings in the terminal box must be knocked out using appropriate methods.
• Take care not to damage the terminal box or its interior components (the terminal board, cable connections,
and so on).
Protruding connection cables
It must be ensured that there are no foreign bodies, dirt or moisture in the terminal base of the machine
enclosure.
• Use O-rings or suitable flat gaskets to seal entries in cover plates (DIN 4925) and other open entries.
• Seal the terminal base of the machine enclosure using the original seal of the cover plate to prevent dust
and water from entering.
• Please observe the tightening torques for cable glands and other screws.
• When performing a test run, secure the feather keys without output elements.
During disassembly and particularly when installing the cover plate, make sure that the connection cables are
not clamped between enclosure parts and the cover plate. Short-circuit hazard!
Final checks
Before closing the terminal box/ terminal base of the machine enclosure, check the following:
• The electrical connections in the terminal box have been made in accordance with the specifications above
and tightened to the required tightening torque.
• The clearances between non-insulated parts have been maintained: ≥ 5.5mm to 690V, ≥ 8mm to 1000V.
• There are no protruding wire ends.
• The connecting cables are laid so that they are not touching one another, to avoid damaging the cable
insulation.
• The machine is connected so that it rotates in the direction specified.
• The inside of the terminal box is clean and free of any pieces of cable.
• All seals and sealing surfaces are clean and undamaged.
• Any unused openings in the terminal boxes have been sealed correctly.
• The pressure relief device is undamaged (depending on the type of terminal box, this involves either cast-
in slots or an overpressure diaphragm). Any damage is only repaired following discussion with the person
responsible for the safety of the installation and using original parts.
Tightening torques
Table Tightening torques for cable glands

28 APF185878
Instruction book

Metal +/-10% Plastic +/-10% O ring

Nm Nm mm
M12 x 1.5 8 1.5
M16 x 1.5 10 2
M20 x 1.5
12 4
M25 x 1.5
2
M32 x 1.5
18
M40 x 1.5
6
M50 x 1.5
20
M63 x 1.5

Tightening torques for screws on the terminal box, end shields, screw-type grounding conductor connections

Thread M4 M5 M6 M8 M10 M12 M16 M20

min 2 3.5 6 16 28 46 110 225
Nm
max 3 5 9 24 42 70 165 340

Tightening torques for self-tapping screws on the terminal box, end shields, screw-type grounding conductor
connections, sheet metal fan covers

Thread M4 M5 M6
min 4 7.5 12.5
Nm
max 5 9.5 15.5

Cable size ZS blowers

CSA/UL

V I total (1) Recommended wire Maximum Recommended wire Maximum

section (2) cable length section (3) cable length
(m) (m)
3xAWG2/0+AWG6 212 3xAWG3/0+AWG6 212
125
ZS 75 440 2x(3xAWG3+AWG6) 167 2x(3xAWG3+AWG6) 167
3xAWG2/0+AWG6 212 3xAWG3/0+AWG6 212
125
ZS 75 460 2x(3xAWG3+AWG6) 167 2x(3xAWG3+AWG6) 167

(1) Current in the supply lines at maximum load

(2) Recommended wire section under standard conditions
(3) Recommended wire section under worst case conditions

Settings overload relay, circuit breaker and fuse for ZS blowers

CSA/UL

APF185878 29
 Instruction book

Main fuses (A) Overload

V I total (1) Q15 (A) F15 (A) (5)
(4) relay F21(A)
ZS 75 440 125 225 (110) 86.00 1.20 1.20
ZS 75 460 125 225 (110) 86.00 1.20 1.20

(4) Fuse value between () valid in case of 6 fuses for parallel supply cables
• Fuse specifications IEC: gL/gG
• Fuse specifications CSA: HRC Form II - UL: Class 5
The fuse protects the starting device, the overload relay protects the motor.
(5) For IT network install fuses instead of a circuit breaker

3.6 Quality of safety components

When installing a remote emergency button or a motor contactor, the following B10d values are advised:
• Emergency stop button: 500 000
• Main contactor: 1 333 333

3.7 Protection of electrical equipment

General
• In order to assure grounding of all conductive components that may be touched by personnel and thereby
eliminating shock hazards, the frame has to be earthed to the same potential as the motor earthing.
• The customer installation has to apply with the local EMC (electro-magnetic compability) regulations.

Protection and switching of motors

Electromechanical starter
The starter is designed to :
• start motors
• ensure continuous functioning of motors
• disconnect motors from the supply line
• guarantee protection of motors against working overloads.
The starter is typically made up of a switching device (contactor) and an overload protection device (thermal
release).
The two devices must be coordinated with equipment capable of providing protection against short–circuit
(typically a circuit-breaker with magnetic release only), which is not necessarily part of the starter.
The characteristics of the starter must comply with the international Standard IEC60947-4-1, which defines
the above as follows :
Contactor
A mechanical switching device having only one position of rest, operated otherwise than by hand, capable of
making, carrying and breaking currents under normal circuit conditions including operating overload
conditions.
Thermal release :

30 APF185878
Instruction book

Thermal overload relay or release which operates in the case of overload and also in case of loss of phase.
Circuit-breaker :
Defined by IEC 60947-2 as a mechanical switching device, capable of making, carrying and breaking currents
under normal circuit conditions and also making, carrying for a specified time and breaking currents under
specified abnormal conditions.
Table 1: Utilization categories and typical applications

Current type Utilization categories Typical applications

Alternating current ac AC-3 squirrel-cage motors:
• starting
• switching off during running

Star-delta starter
The most common reduced voltage starter is the Star-Delta starter (Y-∆), in which :
• On starting, the stator windings are star-connected, thus achieving the reduction of peak inrush current.
Once the normal speed of the motor is nearly reached, the switchover to delta is carried out.
After the switchover, the current and the torque follow the progress of the curves associated with normal
service connections (delta).
As can be easily checked, starting the motor with star-connection gives a voltage reduction of √3, and the
current absorbed from the line is reduced by 1/3 compared with that absorbed with delta-connection.
The start-up torque, proportion to the square of the voltage, is reduced by 3 times, compared with the
torque that the same motor would supply when delta-connected.
This method is generally applied to motors with power from 15 to 355kw, but intended to start with a low
initial resistant torque.

Starting sequence
By pressing the start button, contactors KL and KY are closed. The timer starts to measure the start time with
the motor connected in star. Once the set time has elapsed, the first contact of the timer opens the star-delta
contactor and the second contact, delayed by approximately 50 ms, closes the K∆ contactor, the motor becomes
delta-connected.
Coordination type
• Type 1 (IEC60947-4-1)
It is acceptable that, in the case of short-circuit, the contactor and the thermal release are damaged. The
starter may not be able to function and must be inspected; if necessary, the contactor and/or the thermal
release must be replaced, and the breaker release reset.
• Type 2 (IEC60947-4-1)

APF185878 31
 Instruction book

In the case of short-circuit, the thermal release must not be damaged, while the welding of the contactor
contacts is allowed, as they can easily be replaced (with a screwdriver, for example), without any
significant deformation.
In order to clearly determine a coordination type, and the equipment necessary to achieve it, the following
information must be available:
• Power of the motor in KW
• Motor type
• Rated system voltage
• Rated motor current
• Short-circuit current at installation point
• Starting type :DOL or Y/∆
• Normal or heavy duty operation
• Type 1 or Type 2.
400 V 50kA DOL normal type 2 (Tmax, Isomax-Contactor-TOR)

Motor MCCB Thermal Overload Release

Pe Ir l3 Minimum Maximum
(kW) (A) (A) (A) (A)
0.75 1.90 1.70 2.40
15 28.5 392 29 42
18.5 36 469 36 52
22 42 547 36 52
30 56 840 60 80
37 68 960 60 80
45 83 1200 80 110
55 98 1440 80 110
75 135 1800 130 175
90 158 2400 150 200
110 193 2720 100 320
132 232 3200 100 320
160 282 4000 100 320

500V 50kA DOL Normal Type 2 (Tmax, Isomax-Contactor-TOR)

Motor MCCB Thermal Overload Release

Pe Ir (A)l3 Minimum Maximum
(kW) (A) (A) (A)
0.75 1.5 21 1.3 1.8
11 17.5 240 13 19
15 23 336 18 25
18.5 29 392 22 32
22 34 469 29 42
30 45 624 36 52
37 56 840 45 63
45 67 960 60 80
55 82 1200 65 90

32 APF185878
Instruction book

Motor MCCB Thermal Overload Release

75 110 1440 60 200
90 132 1875 60 200
110 158 2250 60 200
132 192 2720 100 320
160 230 3600 100 320

Standard to fulfil
Selection of cables: IEC 60364-5-52
Protection against overload: IEC 60364-4-43
Starter selection: IEC60947-4-1
Electrical installation: IEC/EN 60204-1
Cables: IEC 60332-1
Wires: IEC60288CI.5
Low voltage switchgear and control gear assemblies: EN 60439-1
Safety of machinery: EN 62061:2005
Safety of machinery: EN 13849-1:2006
Safety of machinery: EN13850
Follow the EMC regulations:
• EN 61000-6-2
• EN 61000-6-4
• ANSI C37.90
Cable selection and fuses: Ul508a or CSA22.2

APF185878 33
 Instruction book

3.8 General pictographs

Pictographs

Reference Name
1 Pictograph, Automatic start - Read manual - No service with voltage and pressure on
2 Pictograph, warning: blow off
3 Pictograph, warning: under tension
4 Pictograph, warning: hot surface
5 Pictograph, transport instructions
6 Stop the blower before maintenance or repair
7 Pictograph, earthing
8 Pictograph, wear ear protection
9 Only use Roto-Z oil
10 Check the air flow direction
11 Rotation direction arrow

34 APF185878
Instruction book

4 Minimum requirements for safe regulation

General
• In order to assure grounding of all conductive components that may be touched by personnel and thereby
eliminating shock hazards, the frame has to be earthed to the same potential as the motor earthing.
• The customer installation has to apply with the local EMC (electro-magnetic compability) regulations.
• All functions and parameters marked with * are only valid if the Blow-off valve is installed. When a Start-
up valve is used, these functions can be ignored.

General settings
Service levels
1. Service level A: show after 4000 hours of running the message “Service level A”.
2. Service level B: show after 16000 hours of running the message “Service level B”.
3. Service level C: show after 24000 hours of running the message “Service level C”.
4. Service level D: show after 40000 hours of running the message “Service level D”.
For the explanation of the service levels, see section Preventive maintenance schedule.
Counters
1. Counter running hours: program a running hour counter
2. Counter loaded hours: program a loaded hour counter
3. Counter Motor starts: program how many times the main motor has started.
4. Counter Load relay: program how many times the load relay has switched.
Check area’s
• At Stop : the blower is switched ON but not running (stopped in automatic operation, programmed stop
or shut-down)
• At Load: the blower is running loaded *
• At Unload: the blower is running, but not loaded (during start-up, or when net pressure has reached unload
pressure)
E.g. when a sensor has to be checked only at Load and Unload phase, the settings (warning, shut-down) will
be ignored at STOP phase.
Automatic restart after voltage failure
• In case an automatic restart after voltage failure or voltage dip is required, the minimum delay since the
voltage failure time to restart the unit has to be 60 seconds. For safety reasons, it is advised to limit the
stop time to a maximum of 500 seconds.

Star Delta specific settings

Graphs
The following graph describes the start, stop and emergency stop functions which will be explained in the
next paragraphs.

APF185878 35
 Instruction book

Graph 1: With start-up valve

Graph 2: With blow-off valve

Text on figures:

(1) Inputs

36 APF185878
Instruction book

(2) Start
(3) Stop
(4) Emergency stop
(5) Outputs
(6) Oil pump
(7) Oil cooler fan
(8) Time
(9) Main motor
(10) Minimum stop time
(11) Unload to load delay time
(12) Blow-off valve

Load/Unload control
• Minimum pressure: 300 mbar(e)
• Loading pressure: Value between “Minimum pressure” and “Unloading pressure”
• Unloading pressure: Value between “Loading pressure” and “Maximum pressure”
• Maximum pressure: maximum working pressure on data plate
Motor starter

Parameter Unit Minimum Advised Maximum

Y-time s 3 7 10
Load delay * s 3 3 120
Starts per day 10 120 240
Y/D transition time ms -- 300 --

Control timers
Minimum stop time:
After stopping, the control system prevents the motor from restarting within a programmed time period. A
start command during this time will be memorized and executed after running out of this period.

Parameter Unit Minimum Advised Maximum

Minimum stop time s 30 30 99

VSD specific settings

Graphs
The following graph describes the start, stop and emergency stop functions which will be explained in the
next paragraphs.

APF185878 37
 Instruction book

Graph 1: With start-up valve

Graph 2: With blow-off valve

Text on figures:

(1) Inputs

38 APF185878
Instruction book

(2) Start
(3) Stop
(4) Emergency stop
(5) Outputs
(6) Oil pump
(7) Oil cooler fan
(8) Time
(9) Motor speed
(10) Setpoint RPM
(11) Minimum RPM
(12) 0 RPM
(13) Minimum stop time
(14) Stop delay time
(15) Unload to load delay time
(16) Blow-off valve

Basic Settings
1. General
If the machine will be driven by a customer installed frequency converter, the following instructions and
installation rules have to be followed in order to guarantee safety and to ensure correct use of the equipment.
• The frequency converter has to be suitable for constant torque applications.
• The minimum and maximum motor speed need to be fixed in the frequency converter.
• The frequency drive installation (incl. the cabling, the grounding and shielding) has to be designed in
order to eliminate or reduce damaging bearing currents protecting the motor bearings against premature
failure.
• Power cables between frequency converter and motor have to shielded.
• The tracing of sensor cables to the machine has to be separate from the power cables.
• The maximum acceleration/deceleration time may never exceed the Ramp-up /Ramp-down time.
2. VSD set-up
Motor parameters
Set up the motor parameters according the motor data plate.
Ramp-up and Ramp-down time
Ramp-up time: ≥10s
• Ramp-up time: Time taken for motor to accelerate from standstill to maximum speed.
Ramp-down time: ≥10s
• (Ramp-down time: Time taken for motor to decelerate from maximum speed to standstill)
Converter Interlock
Contact given by customer controller as a start command for the VSD. When the contact opens, the VSD
will stop.
Motor speed
Minimum and maximum motor speed should be respected.
For specific values, see section Blower data.
3. Start procedure
• Press the “Start” button
• The blower ramps up to minimum speed
• Unload to load delay timer starts counting (See control timers)
• When the timer is past, the blow-off valve closes

APF185878 39
 Instruction book

• The blower starts regulating to the set point

4. Stop procedure
• Press the “Stop” button
• The blower ramps down to the minimum speed
• The blow-off valve opens and the stop delay time starts counting
• The blower will stop when the stop delay timer is past
5. Emergency stop procedure
• Press the Emergency stop button
• Motor will stop immediately
• Blow-off opens immediately without using the stop delay timer
• After an emergency stop, the minimum stop time should be respected
6. Set point Blower (Constant Pressure):
• Value between minimum and maximum pressure, see section Blower data.
7. External speed control (mA control):
Motor speed will be controlled by an external speed signal. Atlas Copco proposes the following procedure:
• Connect mA-signal at the customer controller
• Define start, stop and unload speed
• Stop speed: Reaching this value, the blower will stop. The stop speed can be changed between 0
rpm and the start speed.
• Unload speed: Based on the start and stop speed, the unload speed is calculated *.

• Start speed: Reaching this value, the blower will start-up to the minimum speed. The start speed
can be changed between 0 rpm and the minimum rpm of the blower.
•

Remarks
• During this control, all protection functions remain active.
• The 4-20mA input signal has a working range. If the mA signal is out of range, a sensor error is shown
and the blower needs to shut down.
• It is strongly recommended to use an optocoupler to separate the earth level of the signal coming from
the customer and the earth level of the blower.
8. Control timers

Timer Unit Minimum setting Actual setting Maximum setting

Minimum stop s 30 30 99
time
Unload to load s -- 15 --
delay time
Stop delay time s -- 5 --

Minimum stop time: After stopping, the control system prevents the motor from restarting within a
programmed time period. A start command during this time will be memorized and executed after running
out of this period.

40 APF185878
Instruction book

Communication and communication settings

1. With communication protocol:
Converter interlock (K05-1) must be closed to open the communication channel between PLC and
converter.
When the converter interlock is closed the Blower may start running.
Start sending communication messages to the converter to control the Blower motor.
After stopping the Blower, K05-1 will open and the communication will stop.
2. With 4-20mA communication between PLC and converter:
When the converter interlock (K05-1) is closed the Blower speed will be controlled by the mA signal.
During run, the PLC will read out the speed via a 4-20mA feed back signal.
NC fault contact from the converter will be checked by the PLC.
This contact must be checked in LOAD and UNLOAD phase *.
When the contact is closed momentarily, the Blower motor will run.
When the contact is opened momentarily, the Blower will stop.

Sensors
Temperatures
1. Blower outlet temperature (TT11) (customer installation)
ZS 37-75
• This transmitter is used for warning and shut-down.
• This transmitter must be checked at LOAD and UNLOAD phase *.
• A transmitter failure causes a shut-down.
• Output of transmitter depends on the customer’s installation.
• Range of transmitter is -40 to 340 °C.
• This transmitter has a delay at start of 0 seconds.
• This transmitter has a delay at signal of 0 seconds.
• The recommended warning is 135°C (upper level).
• The recommended shut-down is 140°C (upper level).
2. Oil temperature (TT41) (Customer installation)
• This transmitter is used for warning and shut-down.
• This transmitter must be checked at STOP, LOAD and UNLOAD phase *.
• A transmitter failure causes a shut-down.
• Output of transmitter depends on the customer’s installation.
• Type of thread: G1/4 Range of transmitter is -40 to 340 °C. This transmitter has a delay at signal of 0
seconds.
• The recommended warning is 70 °C (upper level). The recommended shut-down is 75 °C (upper level).
Pressures
1. Pressure transmitter Blower Outlet (PT12) (Customer installation)
• This transmitter is used for warning and shut-down.
• This transmitter must be checked at Stop, Load and Unload phase.
• A transmitter failure causes a shut-down.
• Output of transmitter depends on the customer's installation.
• Range of transmitter is -1 to 5 bar(e).
• This transmitter has a delay at start of 0 seconds.
• This transmitter has a delay at signal of 0 seconds.
• The recommended warning is Setpoint + 0.1 bar(e) (upper level).
• The recommended shut-down is Setpoint + 0.15 bar(e) (upper level).
2. Pressure transmitter Oil Pressure (PT41) (Optional in customer installation)
• This transmitter is used for warning and shut-down.

APF185878 41
 Instruction book

• This transmitter must be checked at LOAD and UNLOAD phase *.

• A transmitter failure causes a shut-down.
• Output of transmitter depends on the customer's installation.
• Type of thread: G1/4
• Range of transmitter is -1 to 5 bar(e).
• This transmitter has a delay at start of:

Minimum Advised Maximum

0s 5s 20 s

• This transmitter has a delay at signal of 0 seconds.

• The recommended warning is 2.2 bar(e) (lower level).
• The recommended shut-down is 2.0 bar(e) (lower level).
3. Oil pressure switch (S1)
• This switch is used for shut-down.
• This switch must be checked at LOAD and UNLOAD phase *.
• A switch failure causes a shut-down.
• Range of transmitter is -1 to 5 bar(e).
• This switch has a delay at start of:

Minimum Advised Maximum

0s 5s 20 s

• This switch has a delay at signal of 0 seconds.

• The recommended shut-down is 2.0 bar(e) (lower level).

Inputs from local control panel on blower:

Push button “Emergency stop” (S3):
• This contact must be checked at Stop, Load and Unload phase.
• This contact is closed in normal operating condition.
• When the contact opens, the blower will stop (shut-down).
Push button “Start” (S0):
• This contact must be checked at Stop phase.
• This contact is open in normal operating condition.
• When the contact is closed momentarily, the blower will start (start command).
Push button “Programmed stop” (S5):
• This contact must be checked at Load and Unload phase.
• This contact is closed in normal operating condition.
• When the contact is opened momentarily, the blower will stop after the minimum stop time.
Push button “Reset” (S2):
• This contact must be checked at Stop, Load and Unload phase.
• This contact is open in normal operating condition.
• When the contact is closed momentarily, the warning and shut-down circuits will be reset. (Only if failure
is solved)
Blower motor failure (overload and/or undervoltage) and Phase seq relay (K5):
• This contact is used for shut-down.
• This contact must be checked at Stop, Load and Unload phase.

42 APF185878
Instruction book

• This contact must be closed in normal operating condition.

• When the contact opens, the blower will stop (shut-down).
Oil pump motor failure (overload and/or undervoltage) (F15/Q15):
• This contact is used for shut-down.
• This contact must be checked at Stop, Load and Unload phase.
• This contact must be closed in normal operating condition.
• When the contact opens, the blower will stop (shut-down).
Oil pressure switch (PT42):
• This contact is used for shut-down.
• This contact must be checked at Stop, Load and Unload phase.
• This contact must be closed in normal operating condition.
• When the contact opens, the compressor will stop (shut-down).

Inputs from remote (customer) control panel:

Remote start/programmed stop (S1’):
This contact must be checked at Stop, Load and Unload phase.
This contact is open in normal operating condition.
When the contact is closed momentarily, the blower will start (start command).
When the contact is opened momentarily, the blower will unload and stop after the minimum stop time.
Remote Load/Unload (S4’):
This contact must be checked at Load and Unload phase.
This contact is open in normal operating condition.
When the contact is closed, the blower will start to unload.
Remote reset:
For safety reasons, a push button “remote reset” is not allowed.
When a shut-down occurs, the blower has to be reset at the local control panel.

Outputs to local control panel on blower:

Lamp Running (K10-1):
• The lamp will light up when blower motor is running.
Lamp Shut down (K11-1):
• This lamp will light up when the blower is in shut-down.
Lamp Voltage On (K12-1):
• The lamp will light up when blower is powered on.

Outputs to customer's installation:

Automatic operation (K07-1):
• This output indicates that the blower is working in automatic mode.
• Contact open: blower stopped (after stop command or shut-down).
• Contact closed: blower running or stopped in automatic mode.

APF185878 43
 Instruction book

Automatic operation: the regulator stops the blower whenever possible to reduce the power consumption and
restarts automatically when the net pressure decreases.
General warning (K08-1):
• This output indicates that the blower is running but has a warning.
• Contact open: blower off or general warning.
• Contact closed: blower on and no general warning.
General shut-down (K09-1):
• This output indicates that the blower has a shut-down and is stopped.
• Contact open: blower off or general shut-down.
• Contact closed: blower on and no general shut-down.

Outputs to Blower components

1. Load/Unload (K03-1):
• Star-Delta starter
• This output will switch the blow-off valve.
Contact is open at standstill.
Contact open: blow-off valve open (unload).
Contact closed: blow-off valve closed (load).
This contact has a delay at start (see start procedure).
This contact opens:
• When the unload pressure is reached.
• When push button Programmed stop is pressed.
• When blower stops after shut-down or emergency stop.
This contact closes:
• 20 seconds after start.
• When pressure decreases to load pressure value.
• Variable Speed Drive
This output will switch the blow-off valve.
Contact is open at standstill.
Contact open: blow-off valve open (unload).
Contact closed: blow-off valve closed (load).
This contact has a delay at start. (See start procedure). This contact opens:
• When the unload pressure is reached.
• During the stop procedure.
This contact closes:
• During the start procedure.
• When the load pressure is reached.
2. Oil pump motor (K01-1)
Oil pump motor will not be controlled through the customer PLC but will start and stop together with line
contactor K21.
3. Fan oil cooler (K04-1)
• In case of use of the Oil temperature sensor (TT41) (Recommended)
This output will start/stop the oil cooler fan (M3)
Contact closed: oil cooler fan running
Contact open: oil cooler fan stopped
Oil cooler fan will start when the oil temperature is higher than 50°C
Oil cooler fan will stop when the oil temperature is lower than 30°C
This control should work continuously even when Blower is stopped
• In case of use of the Pressure switch (S1)

44 APF185878
Instruction book

This output will start/stop the oil cooler fan (M3)

Contact is open at stand still.
Contact closed: oil cooler fan running
Contact open: oil cooler fan stopped
This contact closes when the push button start (S0) is pressed.
This contact opens when the push button programmed stop (S5) is pressed.

APF185878 45
 Instruction book

5 Operating instructions

5.1 Initial start-up

Safety precautions

The operator must apply all relevant Safety precautions.

Special operating conditions

The standard blower is designed for indoor installation at standard operating conditions. In case the blower
has to be installed outdoors, or if the ambient temperature is below -10 °C/14 °F, or if the blower is operated
at high altitudes, modifications and/or precautions have to be taken by the manufacturer. Please consult the
Atlas Copco Compressor Centre.

Moving/lifting
In order not to damage the frame, the blower must be moved either by a lift truck or by using lifting equipment
as described below.
When moving the blower with a lift truck, use the slots in the frame. Make sure that the forks protrude from
the other side of the frame. When moving the blower with a lifting device, insert beams in the slots. Make
sure that the beams cannot slide and that they protrude from the frame equally. The chains must be held parallel
to the bodywork by chain spreaders in order not to damage the blower. The lifting equipment must be placed
in such a way that the blower is lifted perpendicularly. Lift gently and avoid twisting.

Preparation for initial start-up

46 APF185878
Instruction book

1. Install the blower; see sections Electric cable size and fuses, Installation proposal and Dimension
drawing.
2. The blower and motor are secured to the frame immobilizing the vibration dampers during transport.
• Remove bolts (1) and spacers (2) immobilizing the vibration dampers of the blower element.
• Remove support (3) fixing the motor to the frame.
3. Check that the blower is filled with oil: oil must be visible in oil level sight-glass (SG).
4. Switch on the voltage. Start the motor and stop it immediately. Check for correct direction of rotation as
indicated by the arrow on the motor.
• On ZS blowers, if the rotation direction is wrong, switch off the voltage and reverse two electric input
connections.
5. Check all safety functions.
6. Check all blower control functions.
7. Run the blower for a few minutes; stop the blower and check the oil level, which must be in the middle
of sight-glass (SG). Top up, if necessary.

5.2 Before starting

Attention

The operator must apply all relevant Safety precautions.

APF185878 47
 Instruction book

Procedure

1. Check the oil level, which must be in the middle of sight-glass (SG). Top up, if necessary, with the correct
type of oil.
2. Open the air outlet valve (customer's installation).
3. Switch on the voltage.
4. Check the direction of the air flow of the oil cooler fan.

5.3 Taking out of operation

Procedure
At the end of the service life of the blower, proceed as follows:

Step Action
1 Close the air outlet valve, stop the blower and press the emergency stop button.
2 Switch off the voltage and disconnect the blower from the mains.
3 Shut off and depressurize the part of the air net which is connected to the outlet valve.
4 Disconnect the blower air outlet pipe from the air net.
5 Drain the oil, catch the oil in a receptacle. Dispose of the oil according to local regulations.
6 Also read section Used material for the disposal of used material.

48 APF185878
Instruction book

6 Maintenance

6.1 Preventive maintenance schedule

Safety precautions

Before carrying out any maintenance, repair work or adjustment, proceed as follows:
• Stop the compressor.
• Press emergency stop button (S2).
• Close the air outlet valve and open the manual condensate drain valves.
• Switch off the voltage.
• Open and lock the isolating switch (installed by the customer).
The operator must apply all relevant Safety precautions.

Service agreements
Atlas Copco Customer Centres have a range of service agreements to suit your needs:
• An Inspection plan
• A Preventive maintenance plan
• A Total responsibility plan
Contact your Customer Centre to agree on a tailor-made service agreement. It will ensure optimum operational
efficiency, minimize downtime and reduce the total life cycle costs.

Warranty-Product Liability
Use only authorized spare parts. Any damage or malfunction caused by the use of unauthorized parts is not
covered by Warranty or Product Liability.

Service kits
Atlas Copco Customer Centres will be glad to provide you with a wide range of service kits. Service kits
comprise all parts needed for servicing components and offer the benefits of genuine Atlas Copco parts while
keeping the maintenance budget low.

Regular checks
To ensure safe operation and long service life carry out following operations at the interval (period or running
hours) which comes first. The longer interval checks must also include the shorter interval checks. The local
Atlas Copco Customer Centre may overrule the maintenance schedule depending on the environmental and
working conditions of the compressor.

Period Running hours Operation

Daily 8 Check the readings.
Daily -- Check the oil level.
Before starting, the level should be in the middle of the sight-glass.
Weekly -- Drain condensate from the air receiver, if installed
Every 3 months -- Clean blower.

APF185878 49
 Instruction book

Period Running hours Operation

Every 3 months -- Check for possible leaks.
Every 3 months 500 Check the cooler; clean if necessary.
When displayed -- Carry out service actions according to the displayed service plans

Service plan
A number of service operations are grouped (called level A, level B, level C, ...). Each level stands for a
number of service actions to be carried out at the time intervals programmed. See part General settings of
section Minimum requirements for safe regulation.

6.2 Motor greasing

The bearing at the non-drive end side is greased for life.
The bearing at the drive end side is lubricated by the oil system.

6.3 Oil specifications

Roto-Z lubricating oil

Use only Atlas Copco Roto-Z oil which is specially developed for oil-free rotary blowers. This oil has a long
service life and ensures optimum lubrication.
Atlas Copco Roto-Z oil can be ordered in following quantities:

Quantity (l) Ordering number

5 l can 2908 8503 00
20 l can 2908 8501 01
209 l drum 2908 8500 00

50 APF185878
Instruction book

7 Servicing procedures

7.1 Air filter

Location of air filter (AF)

ZS 18 up to ZS 75

Recommendations
1. Never remove the air filter element while the blower is running.
2. For minimum downtime, replace the dirty element by a new one.
3. Discard the element when damaged.

APF185878 51
 Instruction book

Procedure

ZS 18 up to ZS 75

ZS 7 up to ZS 75

1. Stop the blower. Switch off the voltage.

2. Release the snap clips (1) of the air filter (AF) and remove the dust trap (2). Clean the dust trap.
3. Remove and discard the filter element.
4. Fit the new filter element.
5. Reinstall the dust trap.
6. Reset the service indicator (3) by pushing the button in the extremity of the body.

52 APF185878
Instruction book

7.2 Oil and oil filter change

Oil system

Procedure

Step Action
1 Run the blower until warm.
2 Stop the blower.
3 Switch off the voltage.
4 Remove filler plug (FC). Drain the blower sump by opening drain valve (Dm1).
Drain the oil cooler by loosening its drain plugs.
Close the drain valves and tighten the drain plugs after draining.
5 Remove the oil filter. Clean the filter seat, oil the gasket of the new filter and screw the
filter into place until the gasket contacts the seat. Then tighten by hand.
6 Fill the oil sump to the middle of the oil level sight-glass (SG).
See section Oil specifications for the correct type of oil.
7 Reinstall the filler plug.
8 Switch on the voltage.
9 Run the blower for a few minutes.
10 Stop the blower, check that the oil level is in the middle of sight-glass (SG).
11 Top up, if necessary.
12 Dispose of the oil according to the environmental regulations.

7.3 Disposal of used material

Used filters or any other used material (e.g. desiccant, lubricants, cleaning rags, machine parts, etc.) must be
disposed of in an environmentally friendly and safe manner, and in line with the local recommendations and
environmental legislation.

APF185878 53
 Instruction book

8 Problem solving

8.1 Problem solving

Before carrying out any maintenance, repair or adjustment work, stop the blower, switch
off the voltage and close the air outlet valve. Press the emergency stop button. Open and
lock the isolating switch.
The operator must apply all relevant Safety precautions.

Faults and remedies

Condition Fault Remedy

Blower capacity or working Air consumption exceeds Check pneumatic plant
pressure lower than normal capacity of blower
Safety/starting valve leaking Have valve inspected
Air leakage Have leaks repaired
Blower element out of order Consult Atlas Copco
Oil pressure too low Oil level too low Top up level to the middle of the oil level
sight-glass
Oil filter clogged Replace filter
By-pass valve malfunctioning Have valve tested
Oil temperature above normal Oil shut-down temperature Correct setting to trip at the specified
incorrectly set temperature
Insufficient cooling air flow Check the cooling fan
Oil cooler clogged Clean cooler

54 APF185878
Instruction book

9 Technical data

9.1 Readings

Important

The readings below are valid when operating at reference conditions. See Reference
conditions.

Readings on display
For the maximum working pressure and the outlet pressure, consult sections Specific data.
The readings depend on the blower type. The values given below are average values and may differ depending
on the blower type.

Item Reading
Outlet pressure Depends on blower type

9.2 Reference conditions and limitations

Reference conditions

Item Condition
Absolute inlet pressure 1 bar(a) (14.5 psi)
Relative air humidity 0%
Air inlet temperature 20 ˚C (68 ˚F)
Nominal effective working pressure See Blower data.

Limitations

Item Limit
Maximum effective working pressure See Blower data.
Minimum effective working pressure 0.3 bar (4.4 psi)
Maximum air inlet temperature 40 ˚C (104 ˚F)
Minimum ambient temperature -10 ˚C (14 ˚F)

APF185878 55
 Instruction book

9.3 Blower data

Fixed speed, 60 Hz blowers

ZS 75

Gearset F G H
Motor shaft speed rpm 3600 3600 3600
Shaft input
- 800 mBar kW -- -- 57.1
- 900 mBar kW -- 57.7 62.2
- 1000 mBar kW 56.1 62.6 67.3
Temperature at outlet of blower
element
- 800 mBar °C -- -- 89
- 900 mBar °C -- 93 94
- 1000 mBar °C 96 97 98

9.4 Noise level data

Data

0.6 bar(e) with canopy 1.0 bar(e) with canopy

A-weighted emission sound pressure level Lp [dB(A)]
- ZS 75 - 79

56 APF185878
Instruction book

10 Pressure equipment directives

PED instructions
The ZS blowers are pressure assemblies of article 3.3 of 97/23/EC and are subject to good engineering practice.

APF185878 57
What sets Atlas Copco apart as a company is our conviction that
we can only excel in what we do if we provide the best possible
know-how and technology to really help our customers produce,
grow and succeed.
There is a unique way of achieving that - we simply call it the Atlas
Copco way. It builds on interaction, on long-term relationships
and involvement in the customers’ process, needs and objectives.
It means having the flexibility to adapt to the diverse demands of
the people we cater for.
It’s the commitment to our customers’ business that drives our
effort towards increasing their productivity through better
solutions. It starts with fully supporting existing products and
continuously doing things better, but it goes much further, creating
advances in technology through innovation. Not for the sake of
technology, but for the sake of our customer’s bottom line and
peace-of-mind.
That is how Atlas Copco will strive to remain the first choice, to
succeed in attracting new business and to maintain our position
as the industry leader.