# Modbus

**URL:** <https://forum.inductiveautomation.com/t/modbus/2008>\
**Category:** Ignition\
**Created:** [July 6, 2010, 8:17pm UTC](https://forum.inductiveautomation.com/t/modbus/2008 "2010-07-06T20:17:50Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![jaepark](https://avatars.discourse-cdn.com/v4/letter/j/c6cbf5/32.png) [@jaepark](https://forum.inductiveautomation.com/u/jaepark)\
**Post date:** [July 6, 2010, 8:17pm UTC](https://forum.inductiveautomation.com/t/modbus/2008/1 "2010-07-06T20:17:50Z")

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I have a couple difference recording devices. A Honeywell EZTrend QXe and a LogicBeach IL-80  
Using the Ignition UA OPC server,I am able to connect and read the correct data using modbus TCP to the Honeywell unit.  
However on the Logicbeach unit, I get a Bad\_InvalidArgument error in the Quality column.

Using Matrikon OPC I am able to read the data through modbus TCP on both units.  
Modscan32 and SimplyModbus also work on both units.  
Any suggestions?

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**Author:** ![jaepark](https://avatars.discourse-cdn.com/v4/letter/j/c6cbf5/32.png) [@jaepark](https://forum.inductiveautomation.com/u/jaepark)\
**Post date:** [July 8, 2010, 2:22pm UTC](https://forum.inductiveautomation.com/t/modbus/2008/2 "2010-07-08T14:22:33Z")

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Turns out, using 0 as the modbus address instead of 40000 fixed the problem.