Issue
I/A Series G3 Modbus TCP communications to Siemens Moore 353 controller stops updating after a period of time after ENC/JACE reboot or station start. The controllers do not drop offline and the associated Modbus proxy points no longer appear to update.
Environment
I/A Series G3, Modbus TCP 3.6.47 and lower
Cause
Modbus TCP transaction Identifiers are used to associate the future response with the request. The transaction ID is a two byte value that can range between 0 and 65535. The Siemens Moore 353 controller appears unable to process Modbus transaction IDs at or higher than 1024.
Resolution
The I/A Series G3 Modbus TCP driver has been modified to allow the configuring of the maximum transaction ID for each device.
- Download the following modules from The Exchange Download Center:
- Install to the appropriate I/A Series G3 Workbench modules folder and upgrade the modules in the ENC/JACE.
- Modify the transaction ID to a value lower than 1024 and reboot the ENC/JACE station.
