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Modbus TCP stops communicating after a few days

See original GitHub issue

Current behavior I have a flow reading data from a Modbus TCP client. I am using 4 Modbus-Read nodes two with FC1 and two with FC3 reading different ranges. I also added Modbus queue info watching these 4 nodes. All are configured with Unit ID 1, all set to 5 second update.

Expected behavior All works fine, but after a few days or a week no update is read any more. The Modbus nodes show status “active (5sec)” and nothing happens. And in the queue info I see thousands of messages. I added the catch node and used the example to reset the queue on very high, but that does not seem to make a difference either. Btw, in the Modbus Queue Info node the documentation says msg.resetQueue= True, but the example code below uses msg.payload.resetQueue= True; So this is misleading and I have no idea how it is supposed to work. I need to redeploy the flow to make it work.

I am sorry, but I did not find any useful information in the Wiki for this scenario.

Minimal reproduction of the problem with instructions I can give you a demo flow, but I would not post the code here with working Modbus addresses included.

Your Environment

Please tell us about your environment:

(X) I am using just the Node-RED package and got modbus-serial package installed with it
( ) I have installed modbus-serial package global from source (using git clone)
( ) I have installed modbus-serial as a global package (using npm i -g)

Yes, modbus-serial is the name but it does all, TCP and Serial. The node-modbus package is just for the Modbus Server node.

Device :
- ( ) macOS: v
- () Linux: v
- ( ) Windows: v
- (X) Raspbian: v
- ( ) Other:
  - Name:
  - Version:
Description of the connecting Modbus system:
- Name : Saia PLC
- Version:
- Vendor : Saia-Burgess
- Link : https://
node-red-contrib-modbus version: v5.13.3