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AT-MGS-408 User Manual
5. MODBUS
5.1. MODBUS Overview
MODBUS RTU protocol is utilized both for down line detector communication and
up line BMS communication. Communication parameters may be set from the
MODBUS CONFIG menu.
The AT-MGS-408 controller acts as a MODBUS master device on the detector side,
and as a MODBUS slave device on the BMS side.
Main Menu
MODBUS CONFIG
press
OK
to access the
MODBUS CONFIG
menu:
Figure 5-1 -
MODBUS Menu
5.1.1 MASTER BAUD RATE
Slave devices
(gas detectors)
communicate with the master device
(MGS4088
Controller)
at this baud rate, either 9600
(default)
or 19200.
Main Menu
MODBUS CONFIG
MASTR BAUD
press
OK
, to change the
Master BAUD
.
Press the
arrow keys
to select entry, press
OK
.
5.1.2 SLAVE NODE ADDRESS
This is the Modbus node address (1-247) that the upstream BMS will need to use
when sending queries to the controller.
Main Menu
MODBUS CONFIG
SLAVE NODE
press
OK
, to change the slave
node address.
Press the
Up/Down arrows
to select the value,
Left/Right arrows
to move cursor,
press
OK
.
