Weidmuller WI-MOD-945-E: 900Mhz Wireless Ethernet & Device Server v2.16 - Manual (Page 50)

Weidmuller Wireless Ethernet Modem & Device Server WI-MOD-945-E User Manual
Page 50 www.weidmuller.com Rev 2.136
The third mapping takes the 8 registers read by the second mapping and writes them to the serial unit A. The specified
Device ID 5 is the Modbus Address of the serial device A, and the Server IP Address 192.168.0.196 is the IP Address of
the local unit B since the local Modbus TCP to RTU Gateway is to route the message out the serial port to unit A.
Since the WI-MOD-945-E supports Modbus TCP Client and Server simultaneously, the Modbus TCP Server for unit B
above could also be enabled. This would allow one (or more) external Modbus TCP Clients anywhere on the extended
wired or wireless network to connect to unit B and monitor the status of the I/O registers
– including the I/O at units A, C,
and D. This is a very powerful and flexible feature which could, for example, be exploited by a central monitoring facility or
SCADA.
Modbus TCP Configuration on I/O Transfer Menu:
Enable Modbus TCP
Server (Slave) Check this box to enable the onboard Modbus TCP Server. All Modbus
TCP connections to the module IP Address and specified Modbus
Server Device ID will be routed to the onboard I/O registers.
Modbus Server Device ID Specify the Modbus Device ID for the onboard Modbus TCP Server.
Allowed values are 0 to 255.
Enable Modbus TCP
Client (Master) Check this box to enable the onboard Modbus TCP Client. I/O to be
transferred via the Modbus TCP client is specified with Modbus TCP
Client Mappings.
Modbus Client Scan Rate Enter the delay (in milliseconds) between execution of consecutive
Modbus TCP Client Mappings to the same Server.
Reset Registers on
Comm’s Fail When Enabled the value in any onboard I/O register will be reset to zero
if a valid Modbus transaction directed to/from the given register has not
been completed for longer than the Comms Fail Timeout.
Comms Fail Timeout The period of time after which onboard I/O registers will be reset if a
valid Modbus transaction directed at that register has not completed.
Enable Modbus Statistics Enables the Modbus Diagnostic registers as shown in Section 4.9 -
“Internal Diagnostic Modbus Registers”. Disabling this option will free up
the registers and also slightly increase processing resources.
Log background Noise RSSI & BGND on Rx messages are made available in the diagnostic
registers (Section 4.9 -
“Internal Diagnostic Modbus Registers” for
details. For a Hex value of 5F5D the 5D byte = RSSI and the 5F byte =
BGND (Convert value from hex to decimal
and add a “-“e.g. 5F = -
95dB). Enabling this option removes the Background Noise byte from
these registers and so only the RSSI value is made available.
Modbus TCP Client Mappings on I/O Transfer Menu:
Local Register Enter the starting onboard I/O register number that the specified
Modbus Master transaction will transfer I/O to/from.
I/O Count Specify the number of consecutive I/O register to be transferred for the
specified transaction.
Function Code Specify the Modbus Function Code for the transaction.
Destination Register Enter the starting I/O register number in the destination device that the
specified Modbus Master transaction will transfer I/O to/from.
Device ID Enter the Modbus Device ID of the destination Modbus device
Server IP Address Specify the IP Address of the destination Modbus TCP Server for the
specified transaction.