My ESS is using ABB grid meter with ct by RS485 to USB cable. Regulation of grid setpoint always works fine. Recently I found Victrons grid meter node. Reading the values from calibrated ABB meter is always more accurate than values reported by the Multiplus. Mainly frequency and also voltage.
Beside this, the ABB is able to meassure apparent/reactive power and has also Modbus registers for this values. Obviously, the Victron grid meter node only supplies the smallest amount of data what is common to all supported grid meter models. Also did not find any registers for apparent power at the custom input node with dbus access.
What is the recommended method for NodeRed to access this additional data registers?
Recent changes in 3.60 and 3.70 beta have started monitoring Power Factor from grid meters, which is equivalent information. I haven’t seen it work in VRM yet, but maybe that’s just me.
OK, I can confirm that in 3.70~6 beta that the power factor registers above are readable for my Carlo Gavazzi EM530, except that L3 and Total Power Factor are being read as 0 probably due to my having US split-phase.
A power factor of 0.79 is read as 790 in int16. It is definitely signed, meaning that a negative power factor means power is being exported on that phase.
I am assuming when you ask for Watts that you get actual power.
To get apparent power in VA, divide watts by the power factor.
Note that I am not a NodeRED guy, I am reading the ModbusTCP registers directly from the Cerbo.
EDIT: I see the following in the 3.70~5 release notes from MVader.
You may not want to put a beta on a production system.
