Anyone implement something like this but in esphome before? If so, care to share how you did it?
Actual use case: I’d like a way to get notified (other than looking out the window at my neighbors house since they’re too far away) that power has been restored if I’ve flipped the house over to run on generator power during an extended outage. I don’t think a clamp will work since there won’t be any current flowing from the utility side.
Thanks!
Very good question, was wondering the same thing myself.
On one forum I frequent with a bunch of electricians, they came up with a legal (per US code) way to get a low-voltage signal from the mains voltage breaker panel. IIRC, the idea was to attach a small metal electrical box to one of the punch-outs in the side of the breaker box. Then feed a couple of wires to a transformer (I think it was) in the smaller box. The low-voltage output of the transformer would signal the return of power, and could be legally routed outside of the box. Or maybe it was a relay (contactor) in the box, I forget.
That might work if it was just a transfer switch that moved a few select circuits between utility and generator power and the rest of the panel stayed connected to utility power (so the relay or transformer would get no power from the generator but WOULD get city power when it came back on but in my scenario I have an interlock for code purposes that forces the main breaker off before it allows you to energize the panel from the generator - to prevent backfeed. Perhaps something like an inductor?
I came across this and I think it’s a great idea but maybe not so much for ESPhome. Maybe Zigbee would be a better option? I have repurposed a cheap Zigbee window sensors in the past to work with a relay instead of a magnet. You could open up the THP108 sensor and tap into the circuit that drives the alarm. Then connect that to a relay that triggers the Zigbee sensor.