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CGW-MB Installation and Users’ Manual | P/N:LS10248-000HW-E | REV.G | JUL/31/2022
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NFN Network
Modbus Communications
7.7.3 Legacy Modbus CLSS Gateway mainboard
A panel’s network might already be using a Modbus CLSS Gateway mainboard in its
network. You can add the CGW-MB to the network or replace the legacy Modbus CLSS
Gateway mainboard with the CGW-MB.
Replacing the Modbus CLSS Gateway mainboard (Modbus-GW)
Following changes occur when the CGW-MB replaces the Modbus CLSS Gateway
mainboard in the network.
The Mapping of Registers
The CGW-MB and the Modbus CLSS Gateway mainboard have different mapping of
registers.
Example:
The register range for loop-1 detectors:
In the Modbus CLSS Gateway mainboard: 40001 to 40200
In the CGW-MB: 40001 to 40300
Change the client-side scripting as required to change to the registry mapping of the
CGW-MB.
For register mapping details for the CGW-MB, refer to the
Device Types
The device types are different for these two CLSS Gateway mainboards.
Example:
Device Type value of Heat detector:
In the Modbus CLSS Gateway mainboard: 1
In the CGW-MB: 0100H
For device type details for the CGW-MB, refer to the
section.
System Troubles
There are new troubles in the CGW-MB, and some of the system trouble names are
different.
Example 1: New Troubles
In the CGW-MB: 460016-12
th
bit is
Workstation Failure
.
Example 2: Different trouble name
In the Modbus CLSS Gateway mainboard: The
General PS Fault
and the
Power Supply
Trouble
are two different events.
In the CGW-MB: The 460015 - 8
th
bit is one single event for these two.
For system trouble details for the CGW-MB, refer to the
Using Both the CGW-MB and the Modbus CLSS Gateway mainboard
Ensure the following:
•
The
Node Number
of the CGW-MB should be different from other CLSS Gateway
mainboards in the network.
•
The
IP address
of the CGW-MB should be different from other CLSS Gateway
mainboards and devices in the network.
NOTE:
To know the Modbus CLSS Gateway mainboard values of the following, refer to the
document:
LS10015-000NF-E Rev. C2
.
NOTE:
The changes described in the