# Modbus RTU to TCP times out and disconnects

**URL:** <https://forum.inductiveautomation.com/t/modbus-rtu-to-tcp-times-out-and-disconnects/52800>\
**Category:** Ignition\
**Tags:** ignition80\
**Created:** [November 5, 2021, 10:39pm UTC](https://forum.inductiveautomation.com/t/modbus-rtu-to-tcp-times-out-and-disconnects/52800 "2021-11-05T22:39:28Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Kallie\_Winners](https://avatars.discourse-cdn.com/v4/letter/k/a4c791/32.png) [@Kallie\_Winners](https://forum.inductiveautomation.com/u/Kallie_Winners)\
**Post date:** [November 5, 2021, 10:39pm UTC](https://forum.inductiveautomation.com/t/modbus-rtu-to-tcp-times-out-and-disconnects/52800/1 "2021-11-05T22:39:28Z")

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I’m trying to connect an ISCO Signature Flow Meter [https://www.rshydro.co.uk/files/Signature-Manual.pdf](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.

 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/e/1/e127fa23c7cd14033ef9922db90178429cbc9af0.png)

interestingly, when I use a modbus poller I can pull the data.  
 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/7/c/7ccae0c54551437898e88870db65cd3954944ea5.png)

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.

 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/e/5/e56262e8337801c2d6c3b5d260540ee3f5a28fab.png)

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!

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**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\
**Post date:** [November 5, 2021, 10:44pm UTC](https://forum.inductiveautomation.com/t/modbus-rtu-to-tcp-times-out-and-disconnects/52800/2 "2021-11-05T22:44:43Z")

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

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<div class="post-metadata">

**Author:** ![Kallie\_Winners](https://avatars.discourse-cdn.com/v4/letter/k/a4c791/32.png) [@Kallie\_Winners](https://forum.inductiveautomation.com/u/Kallie_Winners)\
**Post date:** [November 5, 2021, 11:11pm UTC](https://forum.inductiveautomation.com/t/modbus-rtu-to-tcp-times-out-and-disconnects/52800/3 "2021-11-05T23:11:31Z")

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