# Modbus TCP/IP Protocol for Mitsubishi PLC not working **URL:** \ **Category:** Ignition\ **Created:** [July 29, 2013, 10:06pm UTC](https://forum.inductiveautomation.com/t/modbus-tcp-ip-protocol-for-mitsubishi-plc-not-working/6948 "2013-07-29T22:06:41Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![ashish007pict](https://avatars.discourse-cdn.com/v4/letter/a/aca169/32.png) [@ashish007pict](https://forum.inductiveautomation.com/u/ashish007pict)\ **Post date:** [July 29, 2013, 10:06pm UTC](https://forum.inductiveautomation.com/t/modbus-tcp-ip-protocol-for-mitsubishi-plc-not-working/6948/1 "2013-07-29T22:06:41Z")
Hi, I am using Ignition to communicate with Mitsubishi PLC Q06 on Modbus Tcp/IP protocol. I have configured all my tags as HRF13000 onwards. I can see these tags in OPC browser and they are all blue (i.e. no errors). But in my tag browser they r showing red false mark. I donr know why it is happening please guide me. I I have checked PLC communication with ping command n it is good ---
**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:** [July 29, 2013, 10:08pm UTC](https://forum.inductiveautomation.com/t/modbus-tcp-ip-protocol-for-mitsubishi-plc-not-working/6948/2 "2013-07-29T22:08:09Z")
There’s probably errors in your console of some sort - can you export and attach or email the logs.bin.gz file? ---
**Author:** ![ashish007pict](https://avatars.discourse-cdn.com/v4/letter/a/aca169/32.png) [@ashish007pict](https://forum.inductiveautomation.com/u/ashish007pict)\ **Post date:** [July 29, 2013, 10:14pm UTC](https://forum.inductiveautomation.com/t/modbus-tcp-ip-protocol-for-mitsubishi-plc-not-working/6948/3 "2013-07-29T22:14:03Z")
whr it is stored ---
**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:** [July 29, 2013, 10:19pm UTC](https://forum.inductiveautomation.com/t/modbus-tcp-ip-protocol-for-mitsubishi-plc-not-working/6948/4 "2013-07-29T22:19:49Z")
On the console page of the Ignition gateway there’s a link to export the logs. ---
**Author:** ![ashish007pict](https://avatars.discourse-cdn.com/v4/letter/a/aca169/32.png) [@ashish007pict](https://forum.inductiveautomation.com/u/ashish007pict)\ **Post date:** [July 29, 2013, 11:27pm UTC](https://forum.inductiveautomation.com/t/modbus-tcp-ip-protocol-for-mitsubishi-plc-not-working/6948/5 "2013-07-29T23:27:14Z")
Pls check uploaded logs file as requested by u [logs.bin.gz](https://us1.discourse-cdn.com/inductiveautomation/original/2X/e/e5eaa67f8559a18b51e909067eca391a543c47a7.gz) (352 KB) ---
**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:** [July 29, 2013, 11:54pm UTC](https://forum.inductiveautomation.com/t/modbus-tcp-ip-protocol-for-mitsubishi-plc-not-working/6948/6 "2013-07-29T23:54:44Z")
The Mitsubishi PLC is returning an error code of 0x04 - Slave Device Failure in response to Ignition’s read requests. Maybe you have the wrong unit ID set up for your configured addresses, or maybe the slave device is offline, or maybe it means something else (consult your PLC documentation…) ---
**Author:** ![ashish007pict](https://avatars.discourse-cdn.com/v4/letter/a/aca169/32.png) [@ashish007pict](https://forum.inductiveautomation.com/u/ashish007pict)\ **Post date:** [July 29, 2013, 11:56pm UTC](https://forum.inductiveautomation.com/t/modbus-tcp-ip-protocol-for-mitsubishi-plc-not-working/6948/7 "2013-07-29T23:56:50Z")
but some addresses are displayed blue in tag browser ok i will look into PLC manual for ur info i m using Q10UDEH ---
**Author:** ![diat150](https://avatars.discourse-cdn.com/v4/letter/d/a587f6/32.png) [@diat150](https://forum.inductiveautomation.com/u/diat150)\ **Post date:** [July 30, 2013, 2:13am UTC](https://forum.inductiveautomation.com/t/modbus-tcp-ip-protocol-for-mitsubishi-plc-not-working/6948/8 "2013-07-30T02:13:43Z")
not sure if this helps you but I always use a software like modbus poll to poll my modbus devices when I am doing initial configuration. its fast and easy to get connected and gives you many options on ordering your floating point data(if you are using floats). Its a very valuable tool and has saved me a headache on many occasions.