Help! Need to find a way to alert when a smart plug drops offline

Hi there. I have a problem I really need to solve quick. I have a house outlet I need to know if it ever loses power. I bought a Samsung Smartthings outlet to plug into the outlet, and if it goes offline, I know the house outlet is no longer receiving power.

The problem is, I get tired of checking every 30 minutes, and can’t check while I’m asleep. I purchased a Dome Siren and want it to go off it the outlet loses power. Any ideas?

Is your Hub, Router and Modem on a UPS? If not, then you aren’t going to ever get notified about anything because the rest of your ST infrastructure will be down and unable to do anything. That’s problem #1. Certain devices will not update their status in ST ever if there is no change to the state. For example, there are door sensors that won’t report back to ST for weeks if the door isn’t opened. I don’t know if the ST outlet falls into that category or not. You can try the smart app "Device Monitor. That might give you what you are looking for.

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Maybe something like this would work?

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The rest of the house does not lose power. The outlet is GFI and trips often. Code does not allow me to change to non GFI.


That looks great, but I don’t see the actual instructions for the project.

Its a simple circuit. USB wall charger connects to the coil side of the relay. When power is on, the coil activates and closes the Normally Open set of dry contacts. The NO set of dry contacts is connected to the Open/Close sensor’s auxiliary input terminals. That’s it.

When power is lost, the relay opens the contacts, and the sensor sends an OPEN signal to ST.

Yeah, I’m not that smart. I need actual instructions. I understand what you are saying but I’m not going to be able to identify the proper points on the circuit board or know how to connect it to the charger. I need a little more hand holding than that.

You can buy one that somebody is selling on amazon…

I have something similar wired for a whole house power sensor and works quite well. Of course, that ties up one of the outlets. What do you have plugged in that you have to monitor so frequently? Also, you might want to look into why the GFCI keeps tripping. If it’s a problem with the outlet itself, it may just need a new GFCI outlet. Or, it may just need it’s ground secured more tightly. I’d be more concerned with that than trying to see when it happens.

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Hi Ryan it’s a long story but I have a refrigerator that must be plugged into a GFCI because it is plugged into a countertop outlet near my kitchen sink. It is the only outlet that a fridge has ever been on or can on be on in my kitchen. I have had two electricians check the GFCI, and it has been replaced twice, with different amperage, and I have had three appliance technicians check the fridge. They acknowledge there is an issue with the fridge. While I am trying to get the fridge fixed under warranty I must endure the changing of parts and then waiting to see if the issue was fixed. This means every time they get it wrong I lose my food. So I would like to use the free outlet to plug in a device that alerts me when the power is out so I can rush home and reset the GFCI.

TL;DR I still need help with the original post.

$70 shipped. Hmm. That’s pretty steep. Does anyone have instructions on how to build one?

I looked, but couldn’t find any online instructions. It really is simply. A total of 4 wires, 2 from the USB power supply (+5v and Gnd) which attach to the relay’s coil side - AND - two from the NO dry contacts on of the relay, attached to the aux input terminals of the Z-Wave contact sensor.

You just need to source the correct relay (5v, dry contacts) and contact sensor, and some wires, plus an old USB wall wart.

If neat packaging is not important to you, you could use this relay from amazon (i.e. this relay is not going to fix inside the Door/Window sensor’s case.)

And this sensor (which appears to have the internal screw terminals for an external switch (in this case, the relay’s normally open contacts.)

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Does anyone know a small cheap z wave device that I can poll to detect power loss?

I don’t know how loud the alarm is, but if it’s like a fire alarm, your could use a Wyze cam to alert you.

Not Z-Wave, but pretty elegant, inexpensive, and should alert anyone in the house to the problem. It is a GFCI outlet, so you could simply replace your existing GFCI outlet with one of these (unless you’re circuit is using a GFCI breaker instead.)

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That’s what I have right now. It’s not very loud and would not wake you up if you were sleeping. It also won’t help when your out of the house.

I really need something for ST.

You could get Google Mesh wifi. Then use IFTTT from google mesh off a trigger if a device goes offline which can then do whatever action you want on ST.

I purchased an RS-232 to Power Over Ethernet (PoE) TCP/IP conversion module to design an AC wall outlet power loss / presence detector that would broadcast the alerts over my home Local Area Network (LAN) to computers and WiFi smart phones etc. A USB wall charger module and relay as described may interface between the AC wall outlet and the RS-232 to TCP/IP conversion module. If readers see this as an over kill, what simpler solution might be pursued? The AC wall outlet is remotely located 200 feet away outside the home and I prefer PoE hardwire over WiFi wireless communications.