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hendrikmuhs / lambda-heatpump-modbus-tcp

Simple script to connect energy meter with a lambda heatpump over modbus tcp
Apache License 2.0
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Modbus connection error #4

Open LaWPde opened 3 months ago

LaWPde commented 3 months ago

Hi, When trying out the programme for the first time using a Fronius inverter+smart meter I received the following error message: "Modbus Error: [Connection] Modbus TcpClient(192.168....): Connection unexpectedly closed 0.001 seconds into read of 8 bytes without response from slave before it closed connection"

In the first moment it seems to connect successfully to both the Fronius and the Lambda but after a few seconds the mentioned error message appears.

The programme runs on a RaspberryPi. First I tested it using a Modbus simulator programme instead of the Lambda heatpump - this worked fine.

Did you ever experience such behaviour? The question is whether the error is caused by the Raspberry or the Lambda HP. It sounds a bit like a timeout at Lambda but I don't have access to any deep settings there. Which E-Meter communication type are you using in the Lambda settings? My setting is "Modbus EM300" what I cannot change myself. (Indeed there is no EM300 smart meter installed, I have the Fronius sm.). If you know: are there any Modbus timeout settings?

hendrikmuhs commented 3 months ago

Hi,

I don't have a Fronius inverter, so I can not help with that. However, I assume it is the Lambda heatpump.

You can try the static mode, that only writes a static value to the heatpump (just replace the ip):

python3 lambda-modbus-tcp.py --source-type static --dest-host 192.168.0.188 -d -i 5 --source-value 1500

My setting is "Modbus EM300" what I cannot change myself

I think this is wrong, it must be set to "modbus tcp". But this requires the "expert" level. Can you ask your craftsmen or support?