"The power is off!" Audible reminder/nagger/alarm.

[Riejufixing]

[Easy-X]

Ah, I'm getting it now... so it's like a super-duper hands free phone that auto answers. Yes you have to unplug it to hoover under the bed etc. and yes you have to unplug it when Nurse Jones is giving old Mr. Fogerty a bed bath (that could be an awkward videophone conversation with the grandchildren!)

So the central problem is somehow reminding ppl to plug it back in when they're done with whatever it is they're doing...

I suggest you get something like this:

https://www.ebay.co.uk/itm/HOT-120db-Power-Cut-Failure-Outage-Automatic-Alarm-Waring-Siren-LED-Indicator/323923624674?epid=2109155946

Take it apart and swap out the siren for something quieter (or jam a rag in it, add some foam sheets to muffle it, etc.)

Then cut the two pin plug off and wire it in parallel inside the plug you want to monitor.
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