I've the same problem with a genset controller, and i've found a walk around:
- Create a new data source for your modbus slave with just one point (the write only register) and without slave monitor points.
- Disable point read exception alarms
- Use an update period of 9999999 hours (it'll bother just at first update, never alarm again 'cause next update will be at 10 years ;))
You need to create a new data source because you need to receive point read exception alarms from all the other read and read/write points on your modbus slave.
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