Known device changing to an "Always On" unknown

My Wood stove fan turns on and off determined by the internal stoves temperature stove internal snap disc (switch). Some days the Sense may detect the stove turning off and on for short times, and cold days when the stove is running constantly and being fed wood it disappears from “Woodstove fan on” device to being included in the “Always On” category. Can you tell me at what point does Sense make it an always on device. I cannot tell my total stove fan total runtime with the changing of the category . Mike


Sense don’t really make a device “Always On”. Always On is a statistical calculation independent of which devices have been detected and which haven’t. This blog highlights the actual calculations, but it is based on the statistics of half-second power samples on each leg of your home circuits over a 48 hour period:

I have always considered the Always On measurement to be directly tied to my daily energy consumption “floor”… Not sure if this is accurate or not, but that’s how I am viewing it…

I have a bunch of air purifiers (3 of them) that I used to keep on 24x7… And I wish that this was not part of Always On (and defined as a “Vampire Draw”)… These are NOT always-on vampire products in my mind… They are legitimate devices/appliances that I have chosen to stay on…

In my mind there is (and should be) a difference between Always-On Vampire energy… and energy that you choose to use on a 24x7 basis…

My fix? Every day or so, I turn off as many things that I can, including those things that I prefer to have on 24x7… This establishes my daily energy consumption “floor” and has a direct impact on what Sense shows as my Always On number.

I hate to game the system… But that’s what I am doing! LOL…


@MikeekiM, you’re thinking about it right. Always On is a “near floor” function.

1 Like

I guess the way I’m looking at the Always On is, my sleeping in the middle of the night usage is approx 123 watts (routers, clocks, night lights, etc). I’ve had this Sense for many years with the theory that I could determine individual device usage, and a known device, with age for example the wood stove fan if it is drawing more current I could tell it was failing or dirty or whatever. Another defeating purpose to having Always On with a known device with a name, I don’t know what the stove fan is costing to use due to its intermittently on and off. hours or days at a time sometimes. I could have many daytime devices which change but never noticed. I thought this was another purpose of Sense. I thought the fewer Always On was the goal

@MikeT - I agree with how you are looking at Always On… In my mind it should represent the minimum power draw when your house is effectively “shut down”. This might mean (as you said) the power draw while you are sleeping. It might mean the power draw when you are on vacation (which in my mind should be even a lower draw than when you are sleeping, but still occupying the home).

And yes…in my mind, the goal would be to drive that Always On number down as low as it could get…

Unfortunately, in my case, I have three air purifiers that often get included in “Always On” because they are always on (duh! LOL)… But I while I do consciously keep them on all time time, I would rather have them identified as devices that I choose to keep on all the time (instead of buried in my Always On and treated like a vampire draw)…

OK… I think I am rambling at this point… I think you understand my perspective… :slight_smile:

Bridging topics a bit, but I think it applies.

As Kevin posted in that thread, its not quite a simple “yes and no”, but I feel this detection process relates to this idea of “Always On” devices and trying to identify “phantom” vs “detected”.

Sense may know about the air purifiers because it recognizes the on, but after a while, it may “lose the trail” to know if its still on. At some point, unless the device has lots of recognizable patterns while running, there is nothing for Sense to track. Sense certainly has more smarts than JUST the on signature to know if something is on, but for lack of a better description, I believe there is some “Educated guessing” going on with some devices.

You may not have experienced it it, but I know every once in a while in the summer, my AC will be off, but Sense still shows it as on. If I go look at the device power meter, you can see a little movement in it, and then it just flatlines for a while before ultimately it turns off. I have always assumed there is some sort of “cleanup” routine that runs to make sure things make sense. That is what I assume eventually turns off AC after a period of time that Sense isn’t sure that it is on.

The way I picture it - some devices are “Easy” for Sense to track. They have an easy to spot “on” signature, and have a visible enough running signature that Sense is able to keep an eye on it.

For others, there is the “estimated guessing”. So something like a fan / or steady motor. Clear start up signature. Over time, Sense learned “if I see start up signature X, it is always followed by a sustained 200w until I see Y signature.” So if I see X sig, and main power consumption increase = 200w, then say device FAN is ON. When power drops by 200w, say FAN us OFF.

I’m sure I’m way over simplifying the detection systems, but in that general direction , this is what makes tracking always on really hard at a device level, vs what it is now, which is a statistical number.

I know its not ideal for what you are looking for, but if you do want to get some breakdown of actual devices within your Always On, your best bet is adding some Sense compatible smart plugs to those devices. That way Sense knows the name of the device, and can attribute it into your Always on.