1500W baseboard heater showing up as 700W on the Sense meter

I have a baseboard heater connected to a Mysa thermostat. Right now, this is the only heater running in the house (my basement office) so its signature is pretty obvious to the naked eye when looking at the Sense meter.

What is puzzling me though, is that the baseboard heater is rated 1500W but the spikes I see on the Sense meter are around 700-750 W high (half of the baseboard’s rated wattage). As far as I know, a baseboard heater is either ON or OFF, but never in-between. I understand that the Mysa thermostat sends short bursts of ON time, but I would expect those bursts to be reported as 1500W by the Sense meter?

That can happen. Sense can discover one leg at a time, then stick the two together because it’s watching each leg independently vs. neutral.

But the meter is displaying the total wattage of both legs, I am pretty sure about that.

Yup, I was just talking about “detection” where Sense can detect each leg separately. You’re right - the Power Meter shows exactly what’s happening on both legs (unless you have a loose CT). If the tagged numbers on the Power Meter line up with the actually delta in the Power Meter (I say that because the numbers come from the detection mechanism so might only be single leg), then your Mysa is only powering one leg. If you are willing to hang out for bit, in the app, you might be able to see the event in the Signals section of the Settings > My Home > Monitor. Turn on your Mysa and you might see one leg jump while the other doesn’t.

Bingo! When I scroll the graph to see the value under the cursor line, the delta of a spike is indeed around 1500W, but the label that appear on the graph indicates a delta of ~750W.


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