Detect Power Failure

#1

1) Give a description of the problem
I want to detect when the power to my house goes out then comes back on. This happened this morning, and eventually everything came back to normal except for 2 Zigbee bulbs which turned on when they had been previously off. I’d like to detect that case, and kill the lights using a piston but only if there was a power failure in the last xx time. Is there a hub status that I can use to detect if it was running on battery then switched to ac power? Or, maybe some other means?

#2

I jerry-rigged my own power fail indicator. I have a zigbee wall socket that I don’t use for anything. I plugged it in close to the hub and when it goes “offline” I know the power failed. Then when it comes back on line I have a few pistons that will fire to make sure the scenes are in the right state. I do this because I keep my hub on UPS along with my router.

#3

Thanks. That’s a good use for a spare adapter.

#4

Another thing you could do is use a Hue bulb. They will turn on automatically when power comes back on because they can’t remember the previous state.

Put one Hue bulb in a place you never ordinarily turn on (like utility closet or something like that). Then monitor it for turning on with a piston. If it does, you will know there was a power outage and that power is now back. Then you can have the piston turn things back off, reset scenes, send you a push notification, etc. Similar concept to RonV42’s approach except with a bulb and switch status vs. offline state.

#5

I get a notification from my Aeon Doorbell.
As you may know it allows devices to play a selected MP3 file you load into it.
When power is restored, it automatically plays the first MP3 file.

I created a file that announces " There has been a power failure. Power has been restored.".
After power comes back on, I hear that notification.