Modbus RTU to TCP times out and disconnects

Ignition
1

I’m trying to connect an ISCO Signature Flow Meter https://www.rshydro.co.uk/files/Signature-Manual.pdf over network to our Ignition gateway and read the tags. The ISCO is modbus 485 output, we are going through a Moxa I3270 to convert over to TCP. The Gateway connects, but the tag status shows disconnected and timeout.

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interestingly, when I use a modbus poller I can pull the data.
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And when I monitor the traffic, the requests from Slave ID 68 and 197 are from the gateway, the requests from the Modbus poller show Slave ID 2.

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I believe the registers are set up properly in the gateway.
So, I’m kind of at a loss because I’m just getting bad data in Ignition.
I could use some fresh ideas if anyone has any. Thank you!

2

If you’ve got a Moxa MGate in front you should just be using the Modbus TCP driver, not RTU over TCP.

3

Effing hell. You’re 100% right. I’m shaking my head in utter disappointment right now. Apparently it’s been a long week.

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