# S7-400 UDT Addressing

**URL:** <https://forum.inductiveautomation.com/t/s7-400-udt-addressing/94766>\
**Category:** Ignition\
**Tags:** siemens\
**Created:** [August 16, 2024, 6:43pm UTC](https://forum.inductiveautomation.com/t/s7-400-udt-addressing/94766 "2024-08-16T18:43:35Z")\
**Posts on this page:** 1\
**Showing post:** 11

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**Author:** ![zxcslo](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/zxcslo/32/61610_2.png) [@zxcslo](https://forum.inductiveautomation.com/u/zxcslo)\
**Post date:** [August 20, 2024, 7:08am UTC](https://forum.inductiveautomation.com/t/s7-400-udt-addressing/94766/11 "2024-08-20T07:08:09Z")

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> [@Attila\_Lazok1](#):
>
> I did.

No, you didn't.  
Why do you keep using `ns=1,s=...`?  
Just do, what @BRYAN_MOBLEY said: put only `[lab_S7_400]DB11,X0.0` in the OpcItemPath.

The syntax `DB11,X0.0` is **CORRECT** one for **Ignition**.

> **[Siemens | Ignition User Manual](https://www.docs.inductiveautomation.com/docs/8.1/ignition-modules/opc-ua/opc-ua-drivers/siemens#address-syntax)**
>
> 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...

The `DBX0.0` is **Siemens** syntax in their software (TIA portal, STEP7).

Have you checked DB11 in the PLC (online) that it is configured correctly?  
Is address 0.0 in DB (online) really configured as boolean?  
Do you REALLY have the latest DB version in the PLC?  
Did you configure the PLC as described in the Ignition instructions? [Siemens | Ignition User Manual](https://www.docs.inductiveautomation.com/docs/8.1/ignition-modules/opc-ua/opc-ua-drivers/siemens#considerations-for-1200-and-1500-devices)  
 ![Screenshot_168](https://us1.discourse-cdn.com/inductiveautomation/original/3X/0/b/0b22874604392594fb443a624fdd8695b6cdeaab.png)

 ![Screenshot_169](https://us1.discourse-cdn.com/inductiveautomation/original/3X/1/9/19dfc904f8fe95888a74c9a0ba8836ada262b3f1.png)

Also, sometimes it happens, if you repeatedly try to configure a tag with wrong data, that '_ **something** _' happens with the Ignition Tag manager (it happened to me a couple of times, especially at the beginning, when I started working with Ignition).  
In that case, it is best to delete all tags (first export all tags without the ones you have problems with) and restart Gateway.  
Then import the tags back and try to configure the tag again.

Also, show us how did you configured the device connection:

 ![Screenshot_171](https://us1.discourse-cdn.com/inductiveautomation/original/3X/1/6/165f437277bccd78f8dc4fcfdf0f84bf4ec34497.png)  
(For s7-300, the CPU slot number is ALWAYS 2.  
For s7-400 is 2 or 3, depends of your power supply (if the power supply is narrow one, then it's 2, if it's wide one, then it is 3)).

and how do you have Ignition OPC UA Server configured:

 ![Screenshot_170](https://us1.discourse-cdn.com/inductiveautomation/original/3X/4/2/421ad875dcc87ba432648ce7a9b9efb38392e009.png)

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