# Issue with multiple modbus getter nodes
**URL:** https://discourse.nodered.org/t/issue-with-multiple-modbus-getter-nodes/77130
**Category:** General
**Created:** [1 April 2023 08:36 UTC](https://discourse.nodered.org/t/issue-with-multiple-modbus-getter-nodes/77130 "2023-04-01T08:36:05Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@henkkas](https://discourse.nodered.org/u/henkkas)
#### Post date: [1 April 2023 08:36 UTC](https://discourse.nodered.org/t/issue-with-multiple-modbus-getter-nodes/77130/1 "2023-04-01T08:36:05Z")
Hello guys,
I have an issue with the use of multiple Modbus-Flex-Getter nodes.
I am working with raspberry pi 3b+ and use following software versions:
I have expanded my project to communicate now with 3 solar inverters and 1 energy meter, on basis of modbus-tcp. As I said I use modbus-flex-getter for data collection. For every connection I have configured a separate modbus-server configuration.
My problem is as follows, now that I have increased from 3 to 4 connections, there is always 1 that is not reading data for some reason. Every time I restart node-red. There is only 3 connections reading data, the one not reading data is quit random. I also tried decreasing polling time from 1 sec to 10 sec, but that doesn't seem to be the cause. The connection that's not reading data, cycles through:
-\>reconnect-\>initialize-\>connected-\>queuing .... and back again.
My question is, is there some sort of limitation on the number of connections you can make, or is there another cause for this problem?
---
### Author:  [@Steve-Mcl](https://discourse.nodered.org/u/Steve-Mcl)
#### Post date: [1 April 2023 11:30 UTC](https://discourse.nodered.org/t/issue-with-multiple-modbus-getter-nodes/77130/2 "2023-04-01T11:30:27Z")
> [@henkkas](#):
>
> My question is, is there some sort of limitation on the number of connections you can make
There will be a limit (memory/CPU/resources) but 4 connections is pretty low.
Likely something something else. Perhaps you are running parallel reads? Or the connection to the fourth device is noisy? Or something else...
---
### Author:  [@henkkas](https://discourse.nodered.org/u/henkkas)
#### Post date: [1 April 2023 12:10 UTC](https://discourse.nodered.org/t/issue-with-multiple-modbus-getter-nodes/77130/3 "2023-04-01T12:10:15Z")
@Steve-Mcl I just found the cause.
I have my running project that I only update with changes after rigid testing these changes on a test RPI.
On my test RPI I communicated 4 times with the same energy meter.
Up to three times went well, but 4 times was somehow too much.
So I implemented the energy meter on my running project and there it worked well, so with 3 inverters and now extra 1 energy meter.
So three times seems too be the max number of connection to 1 IP-address with modbus-tcp.
---
### Author:  [@system](https://discourse.nodered.org/u/system)
#### Post date: [15 April 2023 12:10 UTC](https://discourse.nodered.org/t/issue-with-multiple-modbus-getter-nodes/77130/4 "2023-04-15T12:10:28Z")
This topic was automatically closed 14 days after the last reply. New replies are no longer allowed.