# Tag Read Discrepancy

**URL:** <https://forum.inductiveautomation.com/t/tag-read-discrepancy/98896>\
**Category:** Ignition\
**Tags:** opcua, siemens\
**Created:** [November 20, 2024, 9:29pm UTC](https://forum.inductiveautomation.com/t/tag-read-discrepancy/98896 "2024-11-20T21:29:30Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Alex\_Rayburg](https://avatars.discourse-cdn.com/v4/letter/a/ee59a6/32.png) [@Alex\_Rayburg](https://forum.inductiveautomation.com/u/Alex_Rayburg)\
**Post date:** [November 20, 2024, 9:29pm UTC](https://forum.inductiveautomation.com/t/tag-read-discrepancy/98896/1 "2024-11-20T21:29:30Z")

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Hello I am trying to read a tag from a 1200 series siemen PLC.

Here is my Tag Configuration inside ignition,

 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/1/3/13ecfa22d68e9163b00ddfd97f4ea5f13164b09f.png)

Here is the tag inside of TIA Portal,

 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/3/4/348f65af889fa8602efc1ead0fc93108a4a9eecd.png)  
 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/4/5/45c570b160cd6f902804f4d007a0f3c6acf48af7.png)

The PLC is configured correctly and connected under device connections in the gateway.

PLC: 6ES7 215-1AG40-0XB0  
Firmware: V4.2

Why is the ignition value this large seemingly unrelated number compared to the monitored value in TIA. Is my OPC Item path syntax incorrect? Thank you!

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<div class="post-metadata">

**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 20, 2024, 9:31pm UTC](https://forum.inductiveautomation.com/t/tag-read-discrepancy/98896/2 "2024-11-20T21:31:56Z")

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> [@Alex\_Rayburg](#):
>
> Is my OPC Item path syntax incorrect?

Yes, you need to use the sytnax indicating the datatype is Real (`REAL`) instead of DWord (`D`).

> **[Siemens | Ignition User Manual](https://docs.inductiveautomation.com/docs/8.1/ignition-modules/opc-ua/opc-ua-drivers/siemens#configuring-siemens-addressing)**
>
> The Siemens drivers in Ignition support basic connections to S7 devices. Ignition connects to these PLCs via TCP/IP using the S7 protocol. Similar to Modbus and some Allen Bradley connections, the Siemens S7 devices do not support tag browsing. You...

Try `[Control_TL_1]DB8,REAL22` instead.