# Modbus RTU problem reading address
**URL:** https://discourse.nodered.org/t/modbus-rtu-problem-reading-address/67219
**Category:** Industrial
**Created:** [1 September 2022 15:49 UTC](https://discourse.nodered.org/t/modbus-rtu-problem-reading-address/67219 "2022-09-01T15:49:37Z")
**Posts on this page:** 8
**Page:** 1
### Author:  [@jmm](https://discourse.nodered.org/u/jmm)
#### Post date: [1 September 2022 15:49 UTC](https://discourse.nodered.org/t/modbus-rtu-problem-reading-address/67219/1 "2022-09-01T15:49:37Z")
Hi everyone,
I am using a IoT2050 in order to get data from a temperature controller (the attached document contains the controller's manual). The problem comes when I try to read the registers. The error I get is: "Error: Data length error, expected 7 got 1".
The wiring is correct as IoT2050 can recognize the controller:
I've use this nodes before without this problem and I don't know what can cause this error.
Any help will be welcome!! Thank you in advance
Here is some information about software version:
-Node.js: v12.22.5
-Node red: v2.0.6
-node-red-contrib-modbus: v5.14.1
-server configuration:
-node configuration:
[Eurotherm-3216-3208-3204-User-Manual-Issue13.pdf](https://discourse.nodered.org/uploads/short-url/lWrH3GrbyrdFkU9dX5l8T4i2F5C.pdf) (5.4 MB)
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### Author:  [@UnborN](https://discourse.nodered.org/u/UnborN)
#### Post date: [1 September 2022 18:01 UTC](https://discourse.nodered.org/t/modbus-rtu-problem-reading-address/67219/2 "2022-09-01T18:01:33Z")
Hello .. by reading some similar issues on the Modbus node's [Github page](https://github.com/BiancoRoyal/node-red-contrib-modbus/search?q=Error%3A+Data+length+error%2C+expected+7+got+1&type=issues) some people suggested trying
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### Author:  [@jmm](https://discourse.nodered.org/u/jmm)
#### Post date: [2 September 2022 06:08 UTC](https://discourse.nodered.org/t/modbus-rtu-problem-reading-address/67219/3 "2022-09-02T06:08:55Z")
I've try this and now the meesage is: "Error: Timed out". Also Node red seems to not be ok with this...
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### Author:  [@UnborN](https://discourse.nodered.org/u/UnborN)
#### Post date: [2 September 2022 15:16 UTC](https://discourse.nodered.org/t/modbus-rtu-problem-reading-address/67219/4 "2022-09-02T15:16:51Z")
have you confirmed that the Modbus node's settings for address, baud rate and parity are set the same as with your device's settings (page 90 in the manual) ..
For the node, you need to switch to Serial Expert to see all options
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### Author:  [@jmm](https://discourse.nodered.org/u/jmm)
#### Post date: [12 September 2022 06:12 UTC](https://discourse.nodered.org/t/modbus-rtu-problem-reading-address/67219/5 "2022-09-12T06:12:43Z")
Sorry for the delay.
Yes I've checked all the options. During these days I've doing several test with the computer and other software to ensure that the controller is working properly. The results have been satisfactory, so the problem is with IoT2050 or Node-red
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### Author:  [@jmm](https://discourse.nodered.org/u/jmm)
#### Post date: [13 September 2022 09:33 UTC](https://discourse.nodered.org/t/modbus-rtu-problem-reading-address/67219/6 "2022-09-13T09:33:34Z")
I have tested the Node-red in a different device updating node-red to the last version available (v3.0.2). I've also updated the node-red-contrib-modbus (v5.23.1). Everything works properly so I suppose that the problem is in the IoT2050 periphericals.
Thank you for your help
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### Author:  [@UnborN](https://discourse.nodered.org/u/UnborN)
#### Post date: [13 September 2022 12:38 UTC](https://discourse.nodered.org/t/modbus-rtu-problem-reading-address/67219/7 "2022-09-13T12:38:10Z")
Im glad you managed to get it working in a different device ..
A while back i remember sharing a video i found on the net that describes how they updated the IoT2050 to the latest versions for Node-red and Node-js .. personally im not familiar with the device but here is the [post](https://discourse.nodered.org/t/reading-a-mdb-file/65659/17) in case you want to ask the person that has it if everything is running smoothly.
Also you can try asking on the Siemens if they have any official update procedure.
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### Author:  [@system](https://discourse.nodered.org/u/system)
#### Post date: [27 September 2022 12:38 UTC](https://discourse.nodered.org/t/modbus-rtu-problem-reading-address/67219/8 "2022-09-27T12:38:31Z")
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