Best way to detect electrical circuit outage?

New construction, electrical rough-in phase. My refrigerator and freezer (two separate appliances) will each be on their own circuits, and there's nothing else on those circuits. However, I had the electrician "extend" each circuit into the attic for an outlet on each circuit. My original plan was to have each of the attic outlets power a relay (e.g., Functional Devices Relay-in-a-box). The relays' dry contacts would be wired to zones on the security panel (Elk M1 Gold), so the panel could notify me (voice announcement, email, SMS text, etc.) if either the refrigerator circuit or freezer circuit lost power.

Now that I'm becoming more familiar with HE and z-wave devices, I'm wondering if there is a better/easier solution using the two outlets. I'm okay with trusting HE, et al, to notify me (i.e., not going thru the Elk panel). Or maybe even letting HE notify the Elk panel (if possible). Is there a plug-in device (z-wave preferably) that I can use to easily detect a circuit power outage with HE?

I'm guessing that since a mains device can't communicate if it loses power, it will have to be a device that can be polled. If it doesn't reply, the assumption is that the circuit lost power. I don't need to know immediately, so the polling frequency can be minutes instead of seconds. The benefit to this over a mechanical relay for me is that it would eliminate the wiring between the relay and the panel (about 50' each), and I won't be tying up a couple of zones.

My backup plan to go with whatever I use for the primary method will be battery powered wifi "Temp Sticks" in each appliance that will notify me if the temperature is out of the acceptable range.

Is this a bad idea? If not, what device should I use?

Thanks, Ira

I highly recommend the Zooz ZAC38 range extender. It has a ‘powersource’ state that will easily allow you to monitor the circuits. The outlets in the attic should be a perfect solution for that, too.

Search around for rules discussions and examples. (ETA: I’m mobile, apologies for not providing that.) It’s super simple to implement. I have 3 of them in production.


Yep. I just got a ZAC38 and it has a built-in battery so it will send a Z-Wave message when power is cut (and I have my Hubitat on a UPS so it will receive it). I bought it to be a range extender, but the power outage detector is icing on the cake!

The ring alarm range extender will do this as well, it is also Z-wave. I would probably go with Zooz if I had to buy another though. The Ring extender can be a bit of a hassle to install. Looks like they are about the same price.

I've had a Hue motion sensor in my freezer for two years. I think it's on the same batteries. It tells me if the door is open (lux) or the temp is high. I don't think motion is applicable.

This would be very simple.