Nexus OnCore™ Hardware Manual NCM118586, Ver.
2.6 MDO53 16-Channel Discrete Output Module
2.6.1 Functional Description
The MDO53 16-Channel Discrete Output Module is an intelligent data acquisition and
processing module. It contains a processor subsystem and an acquisition circuit specific
to the digital output function and can provide up to 16 relay outputs. Each digital output
has a dedicated status indication on the cover of the module, and command readback is
also provided by the module.
The module has two redundant intelligent I/O bus (iLink) connectors, which are used to
feed power to the module, communicate with the controller and receive process control
commands from the controller. Field signal wires connect to four 12-pin terminal blocks
located on both sides of the module. Operation status and diagnostics are provided via
indicator LEDs on the front of the module cover.
Figure 2.6-1. Module Front/Rear View
Figure 2.6-2. MDO53 Block Diagram
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NCM118586, Ver. A Nexus OnCore™ Hardware Manual
2.6.2 Installation
2.6.2.1 Installing the Module
Refer to Figure 2.2-3 Nexus OnCore I/O Module Installation and follow the
steps shown below to install the MDO53 module.
1) Determine the module position for the MDO53 in the cabinet, with I/O bus
(iLink) cable installed.
2) Set up the module address jumper per system design. Refer to
Configuration section 2.6.6 for details.
3) Connect the iLink bus cable with the module by its rear DB-9 connectors,
R net – Black, S net – White and tighten the connector screws.
4) If the I/O bus power is present, the module will be powered on. After a
few seconds, the module will go to normal operation.
5) Securely mount the module on the cabinet mounting pillars by its
mounting holes on each corner.
6) Align the module cover with the module base and push it in, until the
upper and lower tabs of the cover securely lock to the module base.
7) Configure the module on the HMI as necessary.
NOTE
The I/O module’s electrical circuit board (PCBA) grounding is provided
through the tinned PCB around board mounting holes. The cabinet’s
mounting pillar connects to the grounding bar through the grounding cables.
The mounting holes of the I/O module’s metal base are specially treated.
Tighten the mounting screws until the module is firmly grounded.
2.6.2.2 Removing the Module
Refer to Figure 2.2-4 Nexus OnCore I/O Module Removal and follow the
steps shown below to remove the MDO53 module.
1) Press the module cover upper and lower tabs simultaneously and remove
the cover from the module base.
2) Unscrew all four corner screws from the module base and remove the
module from the cabinet mounting pillars.
3) Loosen the I/O bus connector screws, which are located on the rear of
the module. Remove the I/O bus cable from the module’s R/S
connectors.
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Nexus OnCore™ Hardware Manual NCM118586, Ver. A
2.6.2.3 Terminal Wiring
Field signal wires connect to four 12-pin terminal blocks located on both
sides of the module. The MDO53 can provide one pair of NO/NC contacts for
each output channel.
Typical 1.5mm2 (#15 AWG or #16 AWG) wires (shielded twisted pair) are
used. Grounding bars are provided adjacent to the cabinet entrance of field
cables for shield grounding. For better shielding and to prevent external
electromagnetic interference, it is recommended that the field cable shield
layer be stripped near the cabinet cable entrance.
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NCM118586, Ver. A Nexus OnCore™ Hardware Manual
COM COM
Control
Loop
NC NC
Control
Loop
RELAY
NO NO
Figure 2.6-3. MDO53 Wiring, Jumper Positions and Cable Connections
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Nexus OnCore™ Hardware Manual NCM118586, Ver. A
2.6.3 Operation
2.6.3.1 Processor
Each I/O module contains a processor circuit which is common to all Nexus
OnCore I/O modules. The processor subsystem is based on ARM®
CortexTM-M3 System-on-chip technology, with high performance and
comprehensive hardware resources integrated into one single chip, including
RAM, flash memory, UART, timer, watchdog, DMA and GPIO. It contains the
following:
High performance CPU with integrated RAM and flash memory
Two independent half-duplex serial communication interfaces, up to
1Mbps I/O bus communication, Plug and Play for bus connection
Embedded I/O module temperature sensor
Three status and alarm LED indicators
Online upgradeability for bootloader/firmware via I/O bus (iLink)
NOTE
At power up, if there is valid firmware in the flash memory, the processor will
go to normal operation within 10 seconds. Otherwise, the processor will
remain in bootloader mode until valid firmware has been downloaded into the
flash memory.
2.6.3.2 Physical Address
Each Nexus OnCore I/O module has a unique physical address within the
same iLink, and this address can be set by the module’s address jumper.
There are four bits used to identify the module’s address, which means up to
16 addresses can be configured (the first 14 addresses are valid). During
module initiation, the process system of the module will acquire a unique
physical address. If the address is the same as any other I/O modules within
the I/O link, communication between the module and controller will not be
established because of address conflict. In such cases, the status LEDs of
the I/O module will indicate the problem. Refer to Diagnostics section 2.6.5
for detailed information.
2.6.3.3 ID Line
The module’s electrical circuitry contains an ID part number which uniquely
identifies the module type. This allows the controller to confirm correct
matching between the target I/O module and the module’s firmware. Five bits
are used to identify module type, which means up to 32 module types can be
identified.
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NCM118586, Ver. A Nexus OnCore™ Hardware Manual
2.6.3.4 Power Management
The Nexus OnCore I/O module includes power management on the 24V dc
input circuit. Transformers are utilized for module power isolation and prevent
short circuit between internal 24V and ground. The I/O module continuously
monitors internal power operation power voltage. Any abnormal condition will
be reported to the controller and alarmed on the HMI screen.
2.6.3.5 Processor Temperature Monitoring
The processor contains a temperature sensor which can be used to measure
actual temperature on the electrical circuit board. The acquired data will be
transferred to the controller via the I/O link by the I/O module.
2.6.3.6 Discrete Output Hardware
The MDO53 has 16 discrete output channels. Each channel applies to
electrical control circuit with voltage class less than 250V AC. Each digital
output section consists of opto-couple isolation, output drive circuit and AC
relay. All output channels are electrically isolated from each other as well as
from the processor and I/O bus.
24Vin - A
MDO53 AC Relay Output DO Module
Isolation Power source
24Vin - B
Power
Source
iLink R
iLink Cable
DB9-R
DO Opto-coupler
Processor
AC Relay
Module
Terminal iLink S
(16 outputs)
iLink Cable
DB9-S
Controller
Figure 2.6-4. MDO53 Hardware Block Diagram
The module accepts digital output commands from the controller, then drives
the output circuit through the opto-coupler to energize the output relay. Each
DO channel has one LED for real-time command indication. If there is a
command output to energize the relay, the corresponding LED will be lit, and
vice versa. Refer to Configuration section 2.6.6 and Installation section 2.6.2
for module configuration and wiring.
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Nexus OnCore™ Hardware Manual NCM118586, Ver. A
2.6.3.7 Status LEDs
Three LEDs are provided on the module’s front panel for operation status
and diagnostics display.
STAT COMR COMS
Figure 2.6-5. I/O Module Status Indicator (LEDs)
Color Label Description
Red STAT Module operation status indication
Green COMR Module communication status indication (iLink R)
Green COMS Module communication status indication (iLink S)
Table 2.6-1. LED Status Indication
For detailed information about Status LEDs, refer to Diagnostics section
2.6.5.
2.6.3.8 Connectors
The module has the following connectors:
Two DB-9 connectors (male) on the rear of the module to connect I/O
bus (iLink) for I/O network connection and 24V dc power supply. Refer
to NCM118585 Nexus OnCore™ System Manual for pin definition of
the connectors.
Four 16-pin removable terminal blocks for field signal wiring.
One programming port (JTAG) on the front of the module’s electrical
circuit board for embedded processor programming and tuning.
2.6.4 Specifications
Item Specification
Number of Channels 16
Output Type Relay output, dry contact
Max Load Current Resistive Load - 12A/250VAC; 12A/30VDC
Inductive Load - 7.5A/250VAC; 6A/30VDC
Response Time On 15 ms typical
Response Time Off 10 ms typical
Contact Material AgNi
Contact Life Electrical operations: 200,000 (AC); 100,000 (DC)
Mechanical operations: 30 x 106 (AC); 50 x 106 (DC)
Frame Rate Refresh all channels within 1ms;
System dependent scan rate for control purposes
Isolation Channel to channel ≥ 1000VAC@50/60Hz
Channel to ground ≥2500VAC@50/60Hz
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Item Specification
Channel to system ≥3000VAC@50/60Hz
Power Supply Dual redundant 24V dc (±10%)
Power Consumption Typical 1.3W, Max 11W
Typical 1.3W, Max 27W (including heat dissipation of external
Heat Dissipation control loop on relay contact)
Physical
Size 209mm x 129.5mm x 51mm (height x width x depth)
Weight 780g
Operating Temperature -20 - 70ºC (-4 - 158ºF)
Storage Temperature -40 - 85ºC (-40 - 18 ºF)
Operating Relative Humidity 5-95% (non-condensing)
Table 2.6-2. MDO53 Specifications
2.6.5 Diagnostics
The MDO53 module performs the following self-diagnostic tests:
1) A power up self-test that includes RAM and flash memory. In case of fault
detection, the module will remain in initialization state, the onboard program will
be halted, and no command will be transmitted.
2) Module’s physical address conflict detection. When an address conflict is
detected, the module will remain offline.
3) I/O link communication check. If any I/O link communication fails, an alarm will be
generated and sent to the controller by the redundant I/O link.
4) Continuous monitoring of the internal power supplies for correct operation. An
alarm will be generated if the power voltage is less than 20V dc.
Details of the individual diagnostics are available from the OptimumC application on the
HMI. The diagnostic signals can be individually latched, and then reset if they become
healthy.
LEDs are provided on the module cover for the module’s status indication.
STAT COMR COMS Description
Solid on Solid on Solid on Module initiating
If all LEDs remain on for a long time, the module’s
firmware may be invalid, or the CPU has failed.
Off Flashing Flashing Normal operation
Flashing Solid on Solid on Module physical address invalid or conflict exists
Flashing Off/Flashing Off/Flashing Internal alarms exist or both I/O communication loss
Per flashing frequency of STAT:
LED flash in turn = In bootloader mode
Flashing Flashing Flashing
LED flash simultaneously = In firmware mode, internal
alarms exist (exclude communication failure)
Flashing Off Flashing iLink R failure, or other internal alarms exist
Flashing Flashing Off iLink S failure, or other internal alarms exist
Table 2.6-3. I/O Module LEDs
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Normally, when the module is powered on, all three LEDs will be on as the module is
initiated. After a few seconds, initiation will be complete, and the processor will start to
run. Depending on the module status, the STAT light will be off or flashing, and the other
two LEDs will stay off until communication between the module and the controller is
established.
In addition, each discrete output channel has its dedicated LED on the module’s cover
for output status indication:
LED Status Meaning
LED On Output command existing, relay is energized
LED Off No output command, relay is de-energized
Table 2.6-4. LED Output Status
2.6.6 Configuration
2.6.6.1 Physical Address Setting
The module’s physical address within the I/O bus can be set by the address
switch. Refer to Table 2.6-5 for all available physical addresses and their
settings.
Table 2.6-5. I/O Module Address Settings
If the OptimumC software version earlier than V2.6.1.2, the module
addresses 12 and 13 are reserved.
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2.6.6.2 Parameter Configuration
Configure the module parameters in the controller configuration prior to using
the MDO53 module.
NOTE
The following information is extracted from the Nexus OnCore system
configuration application. Only hardware related parameters are listed here.
Refer to the Engineer Software Manual and the Function Block Manual for
specific information and detailed operation instructions.
To configure the MDO53 module in SysCfg, click on “Device”, “Link”,
“Module” and “Channel”. Refer to the Engineer Software Manual for detailed
operation instructions.
NOTES
1) For virtual device type, choose “NEXUS”.
2) Insert one “Link” for each I/O link (iLink). It will be mapped as a “Station”
in the controller.
1) Add a module to the controller’s configuration. Insert an I/O module within
the designated “station”. Select “DO53” for the module’s device type.
2) Configure the module’s parameters within the device’s property window.
Parameter Description Choices
Address Module’s physical address 0-13
within the I/O link
Request Controller’s scan rate for the 20, 40, 80, 200, 480, 1000 (units
Interval module are ms)
Description Engineering description for the Text description, manually key in
module
Table 2.6-6. Module Parameters
Figure 2.6-6. MDO53 Module Parameter Setting
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3) Configure each channel of the module. Refer to Figure 2.6-7. Double-
click each row of the module’s output list to configure each I/O point.
Figure 2.6-7. MDO53 Module Output Channel Parameter Setting
Each MDO53 output channel maps an XDO function block. The following
parameters are required for HW related configuration:
Parameter Description Choices
Addr Signal HW address Determined by the module’s
parameter setting and the channel
position within the signal list, read
only
Cvt Conversion type 0=No invert; 1=Invert; 2=SOE, no
invert; 3=SOE, invert.
Table 2.6-7. Parameters Required for Hardware Relate Configuration
2.6.6.3 Failsafe Configuration
The MDO53 module supports the failsafe function. For details, refer to
section 2.4.6.3. Failsafe Configuration of MAO50. The only difference
between the failsafe configuration in the MAO50 and the MDO53 is that the
MDO53 “Outputs” sheet in the SysCfg tool has only one column related to
failsafe, “FailsafeValue”. Select one of three options (“Output_1”, “Output_0”
or “HoldLastVal”) in this column.
2.6.7 Alarms
Alarm ID Alarm Description Possible Cause Solution
32 Channel 1-16 I/O power DC-DC failure. Replace I/O module.
supply voltage low Module DC power Check cabinet DC
supply failure. power supply module.
Table 2.6-8. MDO53 Specific Alarms
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Refer to Table 2.2-9 for the I/O module common alarms.
2.6.8 Ordering Information
Item Code Module Name Description
MDO53 Discrete Output Module Relay Output 16
369B1844G5004 MDO53
channels
Table 2.6-9. MDO53 Ordering Information
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