Anyone know of a good way to detect if non-smart lights are on without having to wire something myself?
Our basement lights are dumb and I’m not looking to make them smart, I’d just like to get a notification if they are on for too long or too late in the night so I can go flip the switch.
All the lights are LED fixtures plugged into switched outlets. I’ve ruled out smart switches because there is simply no room in the boxes of my house for smart switches.
My first idea was a zigbee power monitoring plug, but since the circuit itself gets turned off and on, the plug would not have consistent power and turning it off and on feels like it would have a negative effect on my zigbee network.
My second idea was a power clamp/monitor on one of the lights, but I can’t find one that isn’t basically a “wire it yourself” sort of deal. The problem is that there is not really any other circuits around to power the monitor with and wiring electric is not a core competency I possess. Any issue is that a lot of these monitors hook to mains but aren’t rated for that. I’d love to avoid that.
My third idea is to tape a zigbee light sensor to one of the lights and use the extreme edges of light/dark to signify the on/off state. There are windows in my basement that let some light in, so I think wall mounting would allow for false postives.
Aleternative third option would be to wall mount multiple motion sensors and then check each of them for certain brightness levels and create a binary sensor managed by each of those levels.
Is there another option that I am missing that doesn’t involve rewiring a bunch of stuff?
Yes your best bet is using a lux sensor and adjust it accordingly or get a small relay with a clamp if you can plug it into power nearby to power it if you don’t want to or cannot put one behind the switch you use.
The other option is to get a smart switch that supports power monitoring directly and just swap out the switch with it that fits in the same gang box your current one is in.
What you are trying to do has very limited options in the grand scheme.
I think you can use something that people typically use to sense power failures.
Since your lights are plugged into switched outlets, you need to see if the outlets are on - just like looking for a power failure.
This is what I use for power failures: I have a 5v USB charger plugged into the wall. The output is connected to a 5v relay. The relay is connected to the inputs of a door/window sensor which has separate inputs in addition to the magnet. I use an ecolink DWZWAVE25 but there are others. Any battery-powered sensor that allows you to add a switch should work
The “door” opening and closing tells you when the power to the outlet is on or off - and whether your lights are on and off.
In the past, I used an ESP board (I had a Wemos D1 mini at hand, but others would work as well) that could be powered by the same outlet as the lights. When the Wemos is online, the lights are on, when it’s away they’re off.
Take a look at the new Shelly Mini Gen3 devices, which are even smaller than the Sonoff and might fit in the box with your wall switch. They have a version with a relay (1PM) that makes the circuit smart, and a version with just power monitoring (PM) but no smart switching. The latter might also be installed in your power panel for the entire circuit (up to 16A) if it doesn’t fit in the switch.
I’ve also used the Ecolink DWZWAVE2.5-ECO in order to tell me whether the power is out, exactly like @Schillha mentioned above and it works effectively (though not cheaply) to report power outages.
Lastly, I’m a fan of the Athom Presence sensor, which includes PIR, mmWave, and lux sensors with reporting over WiFi using ESPhome (customizable open firmware). You might be able to calibrate the lux readings using another lux sensor by the window to “subtract” the sun’s influence and determine whether the lights are on, and the radar presence is exceptionally accurate determining if anyone is in the room.