# Modbus tags have bad quality, not sure what to check further **URL:** \ **Category:** Ignition\ **Tags:** modbus, ignition80, ignition81, vision\ **Created:** [October 14, 2025, 11:26am UTC](https://forum.inductiveautomation.com/t/modbus-tags-have-bad-quality-not-sure-what-to-check-further/111432 "2025-10-14T11:26:42Z")\ **Posts on this page:** 17\ **Page:** 1
**Author:** ![hoangduong.vu83](https://avatars.discourse-cdn.com/v4/letter/h/85e7bf/32.png) [@hoangduong.vu83](https://forum.inductiveautomation.com/u/hoangduong.vu83)\ **Post date:** [October 14, 2025, 11:26am UTC](https://forum.inductiveautomation.com/t/modbus-tags-have-bad-quality-not-sure-what-to-check-further/111432/1 "2025-10-14T11:26:42Z")
Hi all, this is my first time setting up Modbus with Ignition. The device here is an Air Compressor with Modbus RTU. I used gateway device USR-TCP232-304 as the bridge to TCP and connected to Ignition successfully. I have created an address following the instruction in the Modbus table but the tag quality is bad. Zero-base is not set to True. I have tried Start: 4006, End: 4007; Start: 4005, End: 4006 as well but no luck, not sure if the address is the problem or not I’m not sure what to check beyond this, any suggestion would be appreciated! ![Screenshot 2025-10-14 221653](https://us1.discourse-cdn.com/inductiveautomation/original/3X/2/4/2457a4d653c58ed11c9e4b6d620124f0553a1cfb.png) ![Screenshot 2025-10-14 221344](https://us1.discourse-cdn.com/inductiveautomation/original/3X/b/e/be21a767ca20df4dff8f39b813ad137c466ea842.png) ![Screenshot 2025-10-14 220618](https://us1.discourse-cdn.com/inductiveautomation/original/3X/c/5/c558e6fae54be7dae3f20e2a73c085aadf9ae125.png) ---
**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:** [October 14, 2025, 12:43pm UTC](https://forum.inductiveautomation.com/t/modbus-tags-have-bad-quality-not-sure-what-to-check-further/111432/2 "2025-10-14T12:43:04Z")
Ditch the address mapping. Try these OPC Item Paths: - `[VOC75 Air Compressor]1.HRF6` - `[VOC75 Air Compressor]1.HRF4006` edit: actually, looking at the docs, those appear to be in hex. Try this as well: - `[VOC75 Air Compressor]1.HRF16390` I don't see any clear indicator from the docs that the data is actually in IEEE 754 floating point format, so you might need to try `HRI` or `HRUI` as well. ---
**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\ **Post date:** [October 14, 2025, 12:46pm UTC](https://forum.inductiveautomation.com/t/modbus-tags-have-bad-quality-not-sure-what-to-check-further/111432/3 "2025-10-14T12:46:17Z")
Hex addresses in docs have always meant zero-based addresses, in my experience. ---
**Author:** ![hoangduong.vu83](https://avatars.discourse-cdn.com/v4/letter/h/85e7bf/32.png) [@hoangduong.vu83](https://forum.inductiveautomation.com/u/hoangduong.vu83)\ **Post date:** [October 15, 2025, 4:15am UTC](https://forum.inductiveautomation.com/t/modbus-tags-have-bad-quality-not-sure-what-to-check-further/111432/4 "2025-10-15T04:15:26Z")
Does it mean that the address are ready to use or I need to change it back by 1? ---
**Author:** ![David\_Stone](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/david_stone/32/79749_2.png) [@David\_Stone](https://forum.inductiveautomation.com/u/David_Stone)\ **Post date:** [October 15, 2025, 6:16am UTC](https://forum.inductiveautomation.com/t/modbus-tags-have-bad-quality-not-sure-what-to-check-further/111432/5 "2025-10-15T06:16:01Z")
> [@hoangduong.vu83](#): > > USR-TCP232-304 Please provide a screenshot of the web config for the USR device, I’ve used them a bunch and you need the settings set up on them correctly in order for ignition to communicate. ---
**Author:** ![hoangduong.vu83](https://avatars.discourse-cdn.com/v4/letter/h/85e7bf/32.png) [@hoangduong.vu83](https://forum.inductiveautomation.com/u/hoangduong.vu83)\ **Post date:** [October 15, 2025, 6:37am UTC](https://forum.inductiveautomation.com/t/modbus-tags-have-bad-quality-not-sure-what-to-check-further/111432/6 "2025-10-15T06:37:44Z")
![Screenshot 2025-10-15 173352](https://us1.discourse-cdn.com/inductiveautomation/original/3X/5/1/51af17c14a9f4a0e3faa801482c0c4306bf5c04b.png) ![Screenshot 2025-10-15 173435](https://us1.discourse-cdn.com/inductiveautomation/original/3X/8/2/8209ee1e60cbd41ff8f8119f36046000418ab186.png) ![Screenshot 2025-10-15 173414](https://us1.discourse-cdn.com/inductiveautomation/original/3X/1/a/1aa03915a72e8f51301c85a1363335a63d34e01b.png) HI David, this is the web config of the device. ---
**Author:** ![hoangduong.vu83](https://avatars.discourse-cdn.com/v4/letter/h/85e7bf/32.png) [@hoangduong.vu83](https://forum.inductiveautomation.com/u/hoangduong.vu83)\ **Post date:** [October 15, 2025, 6:39am UTC](https://forum.inductiveautomation.com/t/modbus-tags-have-bad-quality-not-sure-what-to-check-further/111432/7 "2025-10-15T06:39:42Z")
[Modbus For AirCom.pdf](https://forum.inductiveautomation.com/uploads/short-url/qSPTs50oWWuu0eXqN76n0pkxtJE.pdf) (1.0 MB) This is the modbus document of the air compressor ---
**Author:** ![hoangduong.vu83](https://avatars.discourse-cdn.com/v4/letter/h/85e7bf/32.png) [@hoangduong.vu83](https://forum.inductiveautomation.com/u/hoangduong.vu83)\ **Post date:** [October 15, 2025, 6:40am UTC](https://forum.inductiveautomation.com/t/modbus-tags-have-bad-quality-not-sure-what-to-check-further/111432/8 "2025-10-15T06:40:47Z")
![Screenshot 2025-10-15 173521](https://us1.discourse-cdn.com/inductiveautomation/original/3X/c/9/c9e5852f315a71cccda9c3d83d70c8d89becc0d6.png) ![Screenshot 2025-10-15 173506](https://us1.discourse-cdn.com/inductiveautomation/original/3X/a/0/a0943e5069df7a7a3327c9400e2f8690036f8029.png) ---
**Author:** ![David\_Stone](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/david_stone/32/79749_2.png) [@David\_Stone](https://forum.inductiveautomation.com/u/David_Stone)\ **Post date:** [October 15, 2025, 6:41am UTC](https://forum.inductiveautomation.com/t/modbus-tags-have-bad-quality-not-sure-what-to-check-further/111432/9 "2025-10-15T06:41:41Z")
That Web admin looks correct. the Remote IP tx/rx counter shows the data is actually sending. ---
**Author:** ![David\_Stone](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/david_stone/32/79749_2.png) [@David\_Stone](https://forum.inductiveautomation.com/u/David_Stone)\ **Post date:** [October 15, 2025, 6:47am UTC](https://forum.inductiveautomation.com/t/modbus-tags-have-bad-quality-not-sure-what-to-check-further/111432/10 "2025-10-15T06:47:08Z")
Did you try Kevin's suggestions above? ---
**Author:** ![hoangduong.vu83](https://avatars.discourse-cdn.com/v4/letter/h/85e7bf/32.png) [@hoangduong.vu83](https://forum.inductiveautomation.com/u/hoangduong.vu83)\ **Post date:** [October 15, 2025, 6:55am UTC](https://forum.inductiveautomation.com/t/modbus-tags-have-bad-quality-not-sure-what-to-check-further/111432/11 "2025-10-15T06:55:31Z")
I just tried Kevin’s solution and starting to get some information with HRI16390, below there are values both in integer and float. Pressure must be around 7 bars so maybe it needs some manipulation? ![Integer](https://us1.discourse-cdn.com/inductiveautomation/original/3X/a/d/ad593736a5c0e84ffc20ee14cca76bb874409192.png) ![Float](https://us1.discourse-cdn.com/inductiveautomation/original/3X/2/6/26a59c93cc76c0eb65504e291fc33c1c01b754ad.png) ---
**Author:** ![David\_Stone](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/david_stone/32/79749_2.png) [@David\_Stone](https://forum.inductiveautomation.com/u/David_Stone)\ **Post date:** [October 15, 2025, 7:17am UTC](https://forum.inductiveautomation.com/t/modbus-tags-have-bad-quality-not-sure-what-to-check-further/111432/12 "2025-10-15T07:17:13Z")
> [@hoangduong.vu83](#): > > HRI16390 Try: 1.HRI16389 1.HRI16391 1.HRF16389 1.HRF16391 ---
**Author:** ![hoangduong.vu83](https://avatars.discourse-cdn.com/v4/letter/h/85e7bf/32.png) [@hoangduong.vu83](https://forum.inductiveautomation.com/u/hoangduong.vu83)\ **Post date:** [October 15, 2025, 7:21am UTC](https://forum.inductiveautomation.com/t/modbus-tags-have-bad-quality-not-sure-what-to-check-further/111432/13 "2025-10-15T07:21:41Z")
I tried it as well and it was reading 84,000-ish ---
**Author:** ![hoangduong.vu83](https://avatars.discourse-cdn.com/v4/letter/h/85e7bf/32.png) [@hoangduong.vu83](https://forum.inductiveautomation.com/u/hoangduong.vu83)\ **Post date:** [October 15, 2025, 7:22am UTC](https://forum.inductiveautomation.com/t/modbus-tags-have-bad-quality-not-sure-what-to-check-further/111432/14 "2025-10-15T07:22:57Z")
HRI16391 giving me 7,4ish which I think correct! It’s actually 7,419 (7 thousands) ---
**Author:** ![David\_Stone](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/david_stone/32/79749_2.png) [@David\_Stone](https://forum.inductiveautomation.com/u/David_Stone)\ **Post date:** [October 15, 2025, 7:26am UTC](https://forum.inductiveautomation.com/t/modbus-tags-have-bad-quality-not-sure-what-to-check-further/111432/15 "2025-10-15T07:26:37Z")
Enable zero based addressing and use 16390. ---
**Author:** ![hoangduong.vu83](https://avatars.discourse-cdn.com/v4/letter/h/85e7bf/32.png) [@hoangduong.vu83](https://forum.inductiveautomation.com/u/hoangduong.vu83)\ **Post date:** [October 15, 2025, 7:32am UTC](https://forum.inductiveautomation.com/t/modbus-tags-have-bad-quality-not-sure-what-to-check-further/111432/16 "2025-10-15T07:32:51Z")
I did that and have also retrieved the total running hours of the machine. Thank you guys very much! ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/7/a/7a31998fe1f1ee7e06f23f96ffb58456ef9d4fd9.png) ---
**Author:** ![hoangduong.vu83](https://avatars.discourse-cdn.com/v4/letter/h/85e7bf/32.png) [@hoangduong.vu83](https://forum.inductiveautomation.com/u/hoangduong.vu83)\ **Post date:** [October 15, 2025, 7:34am UTC](https://forum.inductiveautomation.com/t/modbus-tags-have-bad-quality-not-sure-what-to-check-further/111432/17 "2025-10-15T07:34:26Z")
It works with HRI16390, thank you Kevin!