# Help required with Modbus Node

**URL:** <https://discourse.nodered.org/t/help-required-with-modbus-node/77042>\
**Category:** General\
**Tags:** database, modbus, function-node\
**Created:** [29 March 2023 08:06 UTC](https://discourse.nodered.org/t/help-required-with-modbus-node/77042 "2023-03-29T08:06:08Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![italha](https://avatars.discourse-cdn.com/v4/letter/i/5f8ce5/32.png) [@italha](https://discourse.nodered.org/u/italha)\
**Post date:** [29 March 2023 08:06 UTC](https://discourse.nodered.org/t/help-required-with-modbus-node/77042/1 "2023-03-29T08:06:08Z")

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Hello everyone,

I am new to IoT and Node-RED, and currently working on a project to create a power monitoring dashboard on Grafana. For collecting data, I am using an energy analyzer and Node-RED to transfer the data from the energy analyzer to InfluxDB using node-red-contrib-modbus read node with RS485 communication.

However, I am facing a few issues that I need help with:

(i) I read that with a single request, I can read up to 128 16-bit registers. But, I am confused about what constitutes a single request - a complete flow or a node? Additionally, I am only able to read 12 consecutive registers at once with a single node. Is there a way to increase this number with the Modbus-read node?

(ii) I have picked up the timestamp from the registers and want to use it instead of InfluxDB's timestamp. However, when I connect the timestamp reading directly to every node, it gives me an error. Can anyone suggest how to achieve this, particularly if they have experience with InfluxDB nodes?

(iii) As I can only read 12 values per one node, I have a lot of repeating nodes to decode and format these values using different function nodes. Is there a better way to do this?

The node names represent starting register and number of registers. I would be grateful for any suggestions or insights on how to improve my Node-RED flows for this project.

Thank you in advance.

Attached are two screenshots - my flow, and the Modbus server configuration.

 ![flow](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/9/7/97bbb85916fd4b99d076a3ba1e86a52d02245911.png)  
 ![server](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/d/2/d2dfee6ccd24faad8888a6adf69ee358a48767fc.png)

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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:** [28 May 2023 08:06 UTC](https://discourse.nodered.org/t/help-required-with-modbus-node/77042/2 "2023-05-28T08:06:35Z")

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