Modbus TCP devices intermittently disconnecting and reconnecting

[Dustin_Kwok]

Hi I am working with 3 Modbus TCP devices along with a handful of DNP3 devices. The 3 Modbus TCP would intermittently disconnect and reconnect causing countless alarms. Alarms seem to occur every couple minutes with random gaps (15-20 minutes) where everything seems fine. There are three alarms that seem to cycle for each device…

The alarms are as follows:

1. ReadHoldingRegistersRequest -
   

   

2. SocketIODelegate
   

   

3. TimeoutDaemon

Devices are all under one tag group > Direct > 1000ms > subscribed

[pturmel]

You will almost certainly need to collect wireshark captures focused on the problem devices, and start a support ticket. Those errors indicate something broke the TCP connnection between Ignition and the device.