selected tag location1 location2 location3 location4 location5 sourcetag
x outputtag1 1 PLC-ID 106 0 Address sourcetag1
Create a tag ，named “sourcetag1”，set it's pointsource "L"，then modify it's value 。the outputtag1 write to PLC'S address.
I am not a Modbus expert but you can have a look at this to see if it helps.
PI Interface for Modbus PLC
If you are trying to write to a INT16 -> Output single holding register, then your configuration appears to be fine. Are you having issues? Have you tried writing with a modbus tool to that register to confirm that it works properly on that side?
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