Ametek IPS-4-UV, User Manual

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Modbus Communication Interface
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8-3
Analyzer Modbus Interface Parameters
A number of analyzer Modbus interface parameters need to be set up in
order to establish communication with the Modbus master. These pa-
rameters are accessed via the service port on the analyzer using a service
program running on a PC.
Modbus Address
The analyzer needs to be assigned a Modbus slave address, which can be
a number from 1 to 247 .
Modbus Functions
As the Modbus protocol is designed for communication among Program-
mable Logic Controllers (PLCs), not all Modbus function codes supported
by a slave PLC are applicable to the Model IPS-4 analyzer. Only the fol-
lowing relevant function codes are implemented:
In accordance with MODBUS protocol specifications, all address referenc-
es in Modbus messages are numbered relative to zero. For example, the
first holding register in a Modbus slave being referenced as 40001 would
be addressed as 0.
CODE DESCRIPTION
03 read m ultiple holding register (4x references)
06 w rite one holding register (4 references)
16 w rite m ultiple holding registers (4x references)