Weidmuller WI-I/O-9-U2: Wireless Mesh I/O & Gateway User Manual V1.2.2 - Manual (Page 73)

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ID” is used to determine if a Modbus transaction is to be routed to the onboard Modbus
TCP Server or to a Modbus RTU device connected to the serial port. Care should
therefore be taken that all serially connected Modbus devices use different Device
ID’s
(i.e. Modbus Slave Address) as well as being different to the onboard Device ID. Up to
32 separate connections to the Modbus TCP Server are supported.
‘Device ID’ Is the Device ID for the modules own Modbus Server/Slave. This is the ID
that and external Modbus Client or Modbus Master would require to allow it to read
values from the internal Modbus registers, i.e. if a DCS or Scada computer needed to
poll the WI-I/O 9-U2 via TCP or serial connection.
Modbus TCP Client & RTU Master
The Modbus Client Scan rate which is common to both the Modbus TCP Client and
Modbus RTU Master can be set here, the default rate is 1000msec and each mapping
is configured with a response timeout (in this case 1000msec). This time is how long the
master will wait for a response before indicating the failure on the Comms Fail Register.
The ‘Modbus TCP Client’ and ‘RTU Master’ tab further separated into sub tabs which
help spit up and explain each function.
The first subnet ‘Modbus TCP Client’ is where Modbus Client mappings are configured
to communicate with remote TCP devices.
The second sub tab ‘RTU Master’ is where Modbus RTU mappings are configured to
communicate with remote serial Modbus devices.
Modbus TCP Client functionality allows connections to a maximum of 24 different
Modbus TCP Servers and up to 100 mappings can be configured.
All Modbus Mappings are directed to/from the onboard I/O registers depending on
configuration (described below).
The Modbus TCP Client can poll Modbus TCP Servers on either the local Ethernet
network or over the WibMesh radio network.
Mapping parameters
To enter a new mapping select the ‘Add’ button, to edit a mapping select the mapping
you wish to edit from
the table and press the ‘Edit’ button and if you wish to delete a
mapping select the ‘Delete’ button.
Both Modbus TCP Client and RTU Master Mappings are made up of the following
parameters.