# OPC UA with IdentifierType=String on Node-Red

**URL:** https://discourse.nodered.org/t/opc-ua-with-identifiertype-string-on-node-red/4083
**Category:** General
**Created:** [18 October 2018 10:40 UTC](https://discourse.nodered.org/t/opc-ua-with-identifiertype-string-on-node-red/4083 "2018-10-18T10:40:20Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![mec](https://avatars.discourse-cdn.com/v4/letter/m/3ab097/32.png) [@mec](https://discourse.nodered.org/u/mec)
#### Post date: [18 October 2018 10:40 UTC](https://discourse.nodered.org/t/opc-ua-with-identifiertype-string-on-node-red/4083/1 "2018-10-18T10:40:21Z")

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Hi,  
I'm testing OPC UA Client on Node-RED.  
I installed node-red-contrib-iiot-opcua v.3.1.0.  
If I try to read a OPC UA node from client Nod-RED to my OPC UA Server I can read node with IdentifierType=Number (for example: ns=0;i=85) so I'm sure that the connection work fine.  
But if I try to read a node with the IdentifierType=String (for example: ns=36;i=Endpoints.nc1\_r.EndpointSet.nc1\_r500) I have the follow message "Error: String cannot be coerced to a nodeId : ns=36;i=Endpoints.nc1\_r.EndpointSet.nc1\_r500".

Is there a way to read a OPC UA with a string identifier type?

If you need most information ask me.  
Thanks a lot.

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<div class="post-metadata">

### Author: ![mec](https://avatars.discourse-cdn.com/v4/letter/m/3ab097/32.png) [@mec](https://discourse.nodered.org/u/mec)
#### Post date: [18 October 2018 11:40 UTC](https://discourse.nodered.org/t/opc-ua-with-identifiertype-string-on-node-red/4083/2 "2018-10-18T11:40:13Z")

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I finded the solution.

## Examples:

ns=2;s=MyTemperature (namespace index 2, string identifier)  
i=2045 (namespace index 0, numeric identifier)  
ns=1;g=09087e75-8e5e-499b-954f-f2a9603db28a (namespace index 1, GUID identifier)  
ns=1;b=M/RbKBsRVkePCePcx24oRA==' (namespace index 1, Opaque/ByteString identifier)

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### Author: ![chiaradifelice](https://avatars.discourse-cdn.com/v4/letter/c/b3f665/32.png) [@chiaradifelice](https://discourse.nodered.org/u/chiaradifelice)
#### Post date: [16 November 2021 11:31 UTC](https://discourse.nodered.org/t/opc-ua-with-identifiertype-string-on-node-red/4083/3 "2021-11-16T11:31:38Z")

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Hi, I have the same problem. I would to read variable through the variable tree (example root -\> objects-\> fwplchost-\> PLCModules...) instead the node id.  
Is it possible?  
thank you.