# Multiple Modbus Servers Being Read

**URL:** https://discourse.nodered.org/t/multiple-modbus-servers-being-read/34289
**Category:** General
**Created:** [15 October 2020 11:12 UTC](https://discourse.nodered.org/t/multiple-modbus-servers-being-read/34289 "2020-10-15T11:12:27Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![edwardr](https://avatars.discourse-cdn.com/v4/letter/e/e0b2c6/32.png) [@edwardr](https://discourse.nodered.org/u/edwardr)
#### Post date: [15 October 2020 11:12 UTC](https://discourse.nodered.org/t/multiple-modbus-servers-being-read/34289/1 "2020-10-15T11:12:27Z")

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Hi folks,

Having a nightmare at the moment.

I am using Simatic S7 to set up two MB servers to be read off two devices using Node Red, one from my laptop the other from my Rasp Pi.

 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/c/4/c4df5d665de8737f8d86c6d9727d1672feb1e449.png) ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/3/3/3318b51d3a394a0d5c9749a65fe9b793cb2ec1a3.png)  
 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/c/a/ca944de5d7ff1578d2ff49bd4b708b87aa109eae.png)

They both have different ports 503 and 505.

From my laptop, this is the response from node red

 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/3/e/3ecb46a4c18bbf4bc298232f4c3e71e7598894fb.png)  
with correct Siemans PLc set up  
 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/4/8/4865f824de5190a2e499a96142e3a8ef56f1b3bb.png)  
 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/1/d/1d1eba0a03f3a89d12b8ac8125bb484e56dfee6d.png)

My Pi can successfully connect using a second server set up using port 503 and unit Id 1.

I`m confused as to where I`m going wrong here - any ideas?

Thank you in advance.

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### Author: ![system](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/1X/d073cd938eafa2e558d7c2cd59003b3ef4963033.png) [@system](https://discourse.nodered.org/u/system)
#### Post date: [14 December 2020 11:12 UTC](https://discourse.nodered.org/t/multiple-modbus-servers-being-read/34289/2 "2020-12-14T11:12:37Z")

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