Recommendation for whole house power monitor with independent phase amperage readings?
canada_deck
| Posted in General Questions on
Although I’ve followed code, I think I’m pushing the limits on my 200 amp breaker panel. I’m 100% electric. Over the years, additional loads have been added (second washer/dryer for example,) and the house is more fully occupied than it has been than it has been in the past. We also use some power hungry countertop appliances we didn’t have in the past.
I’d like to install a wi-fi based whole home power meter that can provide amperage readings on both phases at a reasonably high frequency (e.g. more than once/minute.) I will have an electrician install it in the main breaker box. Does anyone have any recommendations?
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Replies
You only have one phase. The two hots are opposite halves of the same phase. Residential power is single phase, not two phase, power. The phase angle difference is 180 degrees, two phase would be 120 degrees or 90 degrees.
Anyway, you can monitor total power by monitoring the voltage across the two hots, and total amperage by running the two hots in opposite directions through a single CT (current transformer). Meters can then get total watt and VA measurements from that info, but it won't let you know if you loads are balanced between the two hots.
The two systems I'm familiar with are the Sense and Emporia systems. They both offer similar functionality, with Sense nicer and more expensive, and the Emporia system more of a value offering. Both can provide basic real-time monitoring of seperate lines (like both hots on your service indepenently), along with other branch circuits where needed. The Emporia system is more geared towards independent monitoring of branch circuits though.
Bill