First off, hi everyone, I am a new member from Australia.
I’ve just had a 18kW solar system installed at my house. I have a 3-phase meter, which means I have 3 cables (plus neutral) coming into the main box from the grid, and 3 cables (plus neutral) from the inverter.
I have one simple question:
- I presume the USB power port is use to power the IoTaWatt board, and the 9VAC to sync the phase. How that that work on a 3-phase system? Do I need three transformers? If yes, how are they installed. If not, can the 9VAC be on any of the three phases?
And two related questions (a bit more detailed):
I presume I need 3 sensors for the main feed from the grid, and 3 sensors for the cables from the inverter. I presume this will give me current passing through each of the cables, and that allows me to monitor how much power is generated per phase, and how much power I draw from the grid (or feed into the grid) per phase. Is that correct?
If I run all the 3 cables from the inverter through 1 sensor, I can read how much power is generated by the solar system as a whole (not per phase). Is this correct? Would/won’t the phase difference between the 3 cables (120 degrees apart) affect the reading? I presume I can do the same thing on the grid-side cables as well?