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Hi Guys,
Trying to manually control a Quattro with Cerbo GX via ModBus.
I have followed the ESS mode 2 & 3 documentation.
When ESS mode 3 (external control) is active, the SetPoint wont accept a negative number.
See screen shot to see Charger and Feed-In address status.
Has anyone come across this before?
I have tried -1, -10, -100, -1000 I just get the error as attached. Positive numbers are accepted without issue.
Thanks in advance!
In case someone would like to know, I have already figured out how to write negative values via ModbusTCP in the CCGX in register 2700 of the Register List. This specific register is int16 and admits values between -32768 and 32768, but .... to write negative values you have to send 65536 minus the absolute value to send. Example: if I want to write -50W in the GridSetPoint, via modbustcp I would have to write 65536-50, I mean, 65486.
Por si a alguien le viene bien saberlo, Ya he averiguado como escribir valoras negativos via ModbusTCP en la CCGX en el registro 2700 del Register List.
Este registro concreto es int16 y admite valores entre -32768 y 32768, pero....para escribir valores negativos hay que enviar 65536 menos el valor a enviar absoluto.
Ejemplo: si quiero escribir -50W en el GridSetPoint, via modbustcp tendria que escribir 65536-50, osea, 65486.
Maybe check if you are currently sending a string or number to the Modbus node, if it's not already a number try converting the msg to a number before sending it through.
Thanks for the reply, yes the data is being sent as a number/integer already.
Can anyone let me know what Register and Unit ID they're pushing a negative integer to when using a Cerbo GX? (Note the documentation doesnt list a Unit ID to write to for Cerbo GX)
Thanks
