Weidmuller WI-I/O-9-U2: Wireless Mesh I/O & Gateway User Manual V1.2.2 - Manual (Page 66)

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The default serial parameters of the RS485 port are 9600, N, 8, 1 which match the
defaults of the WI-I/O-EX-1-S serial expansion modules. The parameters can be
changed, to increase poll speeds in larger systems however the serial modules will
need to match that of the WI-I/O 9-U2 RS485 port.
Also if more than 3 serial expansion modules are added the “Maximum Connections” for
the RS485 port on the
“Serial” page will need to be adjusted.
Note: Reducing the “Maximum connections” will slightly improve the
serial scan time however make sure the slave addresses fall within the
“Maximum connections”. If the Slave address is above the “Maximum
connections”, it will not be polled.
Next, connect the serial expansion module and take note of the module address (Rotary
switches on the bottom) as this address will be used as an offset to locate the I/O within
the WI-I/O 9-U2.
Also make sure the last module in the RS485 loop has the termination switch on
(down).
Failure to terminate the RS485 correctly will result in the modules not
operating correctly.
WI-I/O-EX-1-S Expansion I/O Memory Map
I/O data on the WI-I/O-EX-1-S module is read into memory locations according to their
Modbus address. The maximum number of Modbus addresses is 24.
Each WI-I/O-EX-1-S module has an “Offset” which applies to the location of all of its
registers. This Offset is equal to the units Modbus address (selected on the rotary
switch on the end of the WI-I/O-EX-1-S expansion I/O module) multiplied by 20.
If the modules Modbus address is 15, the Offset value will be 15 X 20 = 300.
E.g. If connecting a WI-I/O-EX-1-S-11 (16 x DIO) with address #15

Digital input 1 will be at register location 10301.

Digital Output 1 will be at register location 301
If using a WI-I/O-EX-1-S-12 (8 x DIO & 8 AIN) with address 16

Digital input 1 will be at register location 10321

Analog input 1 will be at register location 30321
See Appendix C: “Expansion I/O Registers”. For a more detailed address map of the
serial expansion I/O modules.
When adding expansion I/O modules to the WI-I/O 9-U2, there are two inbuilt register
associated to indicating the communication status of the expansion I/O module.
 The first is a ‘Communication Fail’ which is located at register location 10019 +
offset value. This register will indicate “1”when the module is in failure.