+200 watts every minute for a few seconds?


Sense has only been running about 2.5 days so far, but whatever this device is has caught my eye with its pattern. The only real detected device so far is our boiler. Earlier today Sense detected a “Light 1” that has 210 watts and runs for 3 seconds very often. I tagged that device to notify me when it started, but when this screen shot was happening “Device 1” was in an off state even though this pattern, visually at least, looks very similar.

+200 watts for 3-5 seconds every minute. It started around 9:30AM and stopped a couple minutes before 3PM. I also saw this yesterday for a while.

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Past discussions make me wanna say a charger of some sort.

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This looks like a heater of some kind. My son has a oil space heater in his room that just surges on and off till it reaches desired temperature! This is what the pattern looks like but these are 700 watt jumps for 1 minute. Just thought it might trigger something for you.


Whatever it is has turned on 404 times so far today starting at 2AM (11:30AM now) for 5-6 seconds each time. This where I wish I had per circuit CT clamps to track it down. :smiley:

Trying to think of any charger/heater devices we have.

The six Taco zone control valves for our forced hot water work on a small internal heater to expand a spring. Those usually heat for 1+ minute at a time and work off 24VAC transformers.

Alarm panel battery is rechargeable.

FiOS optical network terminal has a rechargeable battery.

APC UPS that runs some home automation and network gear 24x7.

Heated mattress pad (it’s off)

Misc phone chargers.

Two laptop chargers (one plugged in)

Two tablet chargers (unplugged)

Roomba vacuum charging dock.

Car battery tender is unplugged.

Bluetooth speaker always in a charging dock.

Hmm… will keep thinking.


I think I may have tracked this down to a heated mattress pad on our bed. I thought it was off when I posted this originally, but my wife’s side may have still been on.

I have been watching Device 1’s history over the last week and it comes on for hundreds of time a day, always for ~3-5 seconds at a time, and it looks like it is almost always overnight and into the morning. Last night I did not turn on my side of the heated mattress pad and I saw no notifications of “Device 1” coming on overnight or into the morning. When you turn on one of the sides it stays on for 10 or 12 hours then turns off by itself.

I turned one side of the pad on this afternoon and the familiar spike that had not showed up all night did show up a few minutes later for a few seconds. In five hours of being on this afternoon it came on only 7 times instead of once per minute as it usually does overnight. I have a suspicion with nobody laying in the bed and the sheets/comforter covering everything the heat isn’t being transmitted out of the pad into the body as quickly so some thermal regulator isn’t being tripped to cycle the coils on and off as often.

Will keep testing…


I think you’re on to something. The other variable - most homes are quieter electrically at night, and it may be more accurately detected then.


I have an electric blanket - pattern looks very similar, so I think your guess of a heated mattress pad is likely correct.


I was able to get a good confirmation this morning. Overnight I had my side on 1 and she had hers on 2. Sense showed the hundreds of hits overnight. Here is the pattern of each side firing, her side is slightly longer at the 2 setting, just before I turn off my side first. You see one more pulse from her side then nothing after I turned it off.

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