So, I’m ready to punch the order button, just want to make sure I have everything right first. Or at least, my order makes sense with the information I have anyway.
I’m actually ordering two systems, one for my apartment, single phase 240v, and one for dad’s place as a Xmas present, 3 phase, 240v with solar and a three phase car charger.
This should be pretty straightforward:
I want to monitor each circuit individually, and will be adding a new circuit next year for a water heater (I’m paying 90 bucks a quarter in connection fees for 3 bucks of gas, can’t wait for the end of that).
So one 100A CT for the main in, and seven 50A CTs for each of the other circuits should be right, correct?
Then one VT and the USB power on a GPO from any of the circuits should give the right readings to calculate everything? From what I understand in the docs, there is no need to measure neutral lines in a single phase, at least, right?
So would I need a CT for each line through the mains breaker? (One per phase)
The car charger breaker has one live line for each phase, plus a neutral line. Would I put a 50A breaker just on each live, or on the neutral too?
The I wouldn’t bother measure the lights or the “shed light + power”, as it’s all efficient lighting and the “shed power” is just running a motion activated outdoor light as well, so a 50A CT on the stove and one for each of the remaining 2 “power” circuits.
I remember reading on someone else’s setup that a solar inverter will have two lines, but you only need to measure one since they’re both the same circuit, so one 50A CT for the solar?
And given power coming in from solar is from a different source than the mains, do I need a VT to measure its voltage? I didn’t see anything in the docs but there wasn’t a lot on measuring solar specifically.
And the AC is 3 phase, so same question as the car charger, three 50A CTs just on the live lines, or four to include the neutral?
Aaaaand my math puts me at a sticking spot, now that I’ve written it down.
IoTaWatt has a 3 ports for VTs and 12 remaining for CTs
3x 100A CTs for main in
3x 50A CTs for car charger
3x 50A CTs for A/C
1x 50A CT for stove
1x 50A CT for Power 1
1x 50A CT for Power 2
And we run out of CTs for solar(1x), let alone if the neutrals need CTs (2x)
Don’t support that ESP32 version with the breakout board is coming soon enough to give a pre-order for Xmas?
If anyone sees any shortcuts that can be taken to make this fit in a single IoTaWatt, I’d love to know how! Could I combine the two power circuits into a single CT if they are the same phase, for example?
Otherwise I guess I’d need 2 IoTaWatts for dad, and have one measure two phases and the second measure the remaining phase and the solar? On the upside, everything would be exactly measured, no inferring anything…
Thanks in advance for any insight!