Something runs every 12 hours in my house

Something is running in my house every 12 hours like clockwork. I can’t figure it out. I know there is a surge of 597 watts and then it tapers out for 123 watts for the next 40 mins. Its the same each time every 12 hours. Sense identifies it as 99% chance its a fridge. I have two fridge/Freezer double door refrigerators and a reach in Freezer. I have turned down all of the refrigerator’s and freezers to the lowest setting, and its showing as still running. Anyone know what that is?

Any pictures of waveforms ? That might help. You can see some typical waveforms for different devices here.
https://community.sense.com/c/device-detection/device-library

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As @kevin1 requested, a waveform would help in identification.

Trusting Sense’s designation, a 12 or 24hr cycle sounds like it could well be the defroster element in one of your fridge/freezers – it’s in the realm of wattage for those, if a little on the high/long side.

Refrigerator defroster? This is what my refrigerator looks like. Does this about every 12 hours.

I suspected it be the defroster in the fridge. But why would the defroster register separate from the Fridge? Shouldn’t it be all under one device? I went ahead and merged the kitchen fridge and the defroster together.

Two more thoughts:

  • the starting spike is an inductive spike typical when motors start. It’s hard to read much from the height of the spike in the apps half-second view of it. But Sense is using a detailed (microsecond) view to figure out what type of device it is seeing. Don’t try to read too much into the spike height number.
  • The body of the bump is a better indicator of the size of the motor.

I flipped the breaker on the fridge, and noticed that sense readings stopped. So I know its for this fridge by itself. The Fridge has its own wave form.

Many devices are composed of different electric elements that turn on and off at different times, sometimes in concert with one another, sometimes completely separately. The way Sense works, it detects the “physics” of the individual elements (motors, heating elements, lights, etc.) starting and stopping. If they regularly occur close together, Sense might eventually merge them. If you figure out they are connected, you can merge them, though there are some good reasons not to manually merge them.

Any reason why it should not be merged?

Two reasons that I usually don’t merge devices right away

  • I want to wait until I know the Sense detections are completely consistent. I have done merges, mostly with my AC units, where the identification of one element (a spike) drifted back and forth between by two AC units based on season. Merging kept me from seeing the inconsistent pattern of this spike for a while. I have long examination of this drift in the Data Analysis category.
  • There isn’t super high value to human merging if you just do intelligent naming. Sense might eventually decide to merge automatically. My druthers is to wait for that.
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I forgot to mention that my refrigerator is on a TP-Link smart plug. Sense never found my refrigerator.

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Like @kevin1, at this stage I would put Merging in the Too Lazy bin … i.e. let Sense do it when it gets around to it. Meantime, as other have pointed out you may actually want to account (and set Notifications) for the individual components of Devices. e.g. Fridge light on = Fridge door open = Racoon alert!

Consider: When Sense eventually does auto-merging, what it’s doing is re-aggregating electrical signatures (“devices”, small-d) while potentially keeping track of the sub-signatures of a particular “Device” (capital-D). This could retain the ability to trigger device-based (small-d) notifications or even display a Device (capital-D) waveform with all its sub-component device (small-d) waveforms stacked. Wouldn’t that be nice!

Could be a fridge or freezer in defrost cycle. Mine runs at 454 watts for 11 minutes approximately every 12 hours.

My fridge has a few detections.
One each for compressor, door light, water/ice dispenser and defrost.