Modbus-TCP communication not starting

[robsy]

Hi,

after installing and configuration of ModbusPV the following error happens:
Modbus Error: [Input/Output] Modbus Error: [Invalid Message] No response received, expected at least 8 bytes (0 received)

Modbus TCP is enabled at the inverter-dongle (SUN2000-10KTL-M1), and "reachable", because if disabled at the inverter connection is completely refused (different failure).

Do you have any idea howto start searching the failure?

Robert

[klein-artur]

Hi,

first thanks for trying it with ModbusPV.

Have you activated full access (I never tried it without full access, honestly):

What is your configuration for "Start address for automatic address allocation"?

Did you change anything on the registers in ModbusRegisters.py or the UNIT in ModbusTCPReader.py?

There is a cli integrated in the project: Server/readerCli.py. You can call it like this:

.\readerCli.py [ip_address] [register_address] [lenght] [slave]

A good way to test your connection could be to call the cli like this:

readerCli.py [ip_address] 37760 1 1

It should return the current batter state*10. So if your battery has left 50 % it will return you 500. Does this work or do you get any better error message?

[klein-artur]

@robsy Any update on this?