# Unable to read serial data in Node red

**URL:** <https://discourse.nodered.org/t/unable-to-read-serial-data-in-node-red/94972>\
**Category:** General\
**Created:** [29 January 2025 06:04 UTC](https://discourse.nodered.org/t/unable-to-read-serial-data-in-node-red/94972 "2025-01-29T06:04:54Z")\
**Posts on this page:** 10\
**Page:** 1

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**Author:** ![Babu6727](https://avatars.discourse-cdn.com/v4/letter/b/ed8c4c/32.png) [@Babu6727](https://discourse.nodered.org/u/Babu6727)\
**Post date:** [29 January 2025 06:04 UTC](https://discourse.nodered.org/t/unable-to-read-serial-data-in-node-red/94972/1 "2025-01-29T06:04:54Z")

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I am getting data from the Modscan. but the same configuration is not working in Node-RED. need help on this situation  
Node-RED Version : V4.0.8  
Device : CR800 wms data logger  
MOC: SerialR232 to USB

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**Author:** ![TotallyInformation](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/totallyinformation/32/31_2.png) [@TotallyInformation](https://discourse.nodered.org/u/TotallyInformation)\
**Post date:** [29 January 2025 14:35 UTC](https://discourse.nodered.org/t/unable-to-read-serial-data-in-node-red/94972/2 "2025-01-29T14:35:10Z")

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Welcome to the community but I'm afraid that there is nowhere near enough information in your post for anyone to be able to help.

What OS?

Have you checked in the OS that the device is connected to the port you anticipate?

Have you checked in the OS that your node-red user has access to the port?

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<div class="post-metadata">

**Author:** ![Babu6727](https://avatars.discourse-cdn.com/v4/letter/b/ed8c4c/32.png) [@Babu6727](https://discourse.nodered.org/u/Babu6727)\
**Post date:** [29 January 2025 15:48 UTC](https://discourse.nodered.org/t/unable-to-read-serial-data-in-node-red/94972/3 "2025-01-29T15:48:58Z")

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Thank you for the reply.  
It's is connect via RS232 to usb converter to the windows 10 system.

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**Author:** ![Babu6727](https://avatars.discourse-cdn.com/v4/letter/b/ed8c4c/32.png) [@Babu6727](https://discourse.nodered.org/u/Babu6727)\
**Post date:** [29 January 2025 15:51 UTC](https://discourse.nodered.org/t/unable-to-read-serial-data-in-node-red/94972/4 "2025-01-29T15:51:29Z")

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![IMG20250129113825](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/5/f/5fd1d74a396b70c6ff02d3d87c70f7636653e89a.jpeg)  
Check  
 ![FB_IMG_1738166072932](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/6/4/645cdc2c06577968b5aebfe4f54e7913ff334fbd.jpeg)

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**Author:** ![krambriw](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/krambriw/32/5429_2.png) [@krambriw](https://discourse.nodered.org/u/krambriw)\
**Post date:** [29 January 2025 17:05 UTC](https://discourse.nodered.org/t/unable-to-read-serial-data-in-node-red/94972/5 "2025-01-29T17:05:11Z")

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I assume you cannot connect to the port from Node-RED and the tool at the same time (conflict)

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<div class="post-metadata">

**Author:** ![Babu6727](https://avatars.discourse-cdn.com/v4/letter/b/ed8c4c/32.png) [@Babu6727](https://discourse.nodered.org/u/Babu6727)\
**Post date:** [30 January 2025 02:41 UTC](https://discourse.nodered.org/t/unable-to-read-serial-data-in-node-red/94972/6 "2025-01-30T02:41:06Z")

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This is just for reference only. I close the Modscan before injecting in Node-RED.  
Data Reading in Modscan but same configuration not working in Node-RED

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**Author:** ![Steve-Mcl](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/steve-mcl/32/4826_2.png) [@Steve-Mcl](https://discourse.nodered.org/u/Steve-Mcl)\
**Post date:** [30 January 2025 06:31 UTC](https://discourse.nodered.org/t/unable-to-read-serial-data-in-node-red/94972/7 "2025-01-30T06:31:22Z")

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> [@Babu6727](#):
>
> I close the Modscan before injecting in Node-RED

You will need to restart node-red (or do a full deploy) to reinitialise the serial connection.

If that doesn't work, share screenshots of setup details of your node and the scan program.

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<div class="post-metadata">

**Author:** ![Babu6727](https://avatars.discourse-cdn.com/v4/letter/b/ed8c4c/32.png) [@Babu6727](https://discourse.nodered.org/u/Babu6727)\
**Post date:** [30 January 2025 06:44 UTC](https://discourse.nodered.org/t/unable-to-read-serial-data-in-node-red/94972/8 "2025-01-30T06:44:05Z")

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I have tried to restart Node-red. but the result are same. here i attached the screenshot for your referenec

[grid]

 ![s3](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/0/a/0afc5af3efacb59b081cb3da653e31b60ed7d011.png)  
 ![s4](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/d/0/d0318d70532d7af70b9d0eb59ef170cea4791dc2.png)

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<div class="post-metadata">

**Author:** ![Steve-Mcl](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/steve-mcl/32/4826_2.png) [@Steve-Mcl](https://discourse.nodered.org/u/Steve-Mcl)\
**Post date:** [30 January 2025 06:54 UTC](https://discourse.nodered.org/t/unable-to-read-serial-data-in-node-red/94972/9 "2025-01-30T06:54:40Z")

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Sharing only the non working config without any detail is not really helpful.

> [@Steve-Mcl](#):
>
> share screenshots of setup details of your node and the scan program.

So we can compare the working config of mobus scan application Vs non working node red.

* * *

Also, just as a double check, please confirm when you restarted node-red the modbus scan program was NOT running. In fact, do a restart to ensure the com port is released (and don't open the scan application)

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<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/1X/d073cd938eafa2e558d7c2cd59003b3ef4963033.png) [@system](https://discourse.nodered.org/u/system)\
**Post date:** [30 April 2025 06:55 UTC](https://discourse.nodered.org/t/unable-to-read-serial-data-in-node-red/94972/10 "2025-04-30T06:55:17Z")

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