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Okay, need help on this ASAP

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Aiight, with this hurricane that's coming and threatens to take out power for quite a few days a friend of mine wants me to make something for him, see his mother is on an oxygen machine, and something else that if the power were to go out in the middle of the night and not come back on until the morning, she'd be dead, they're already ready to be hooked up to a backup generator, but the only one he was able to get is gasoline, so he wants me to rig up a emergency buzzer, basically a 40 Db buzzer that turns on when the power goes out so he can start up the generator, only he wants to be able to have a power off, and a reset switch, so he can turn it off while the power is out, and reset it when the power comes back on.

So it'd be 110 Ac to whatever the parts require, but I want it to be about the size of a DC adaptor, no bigger, something portable, I've already got a case, and a couple of buzzers I can use, just need help with a schematic, and the rest of the guts, I've never worked with emergency stuff before, and I can only find stuff for emergency lighting, but that's way too huge to use especially if it's wall mounted.

Update on the situation, hurricane is going to be here in about 2 days, so I'd appreciate some responses quickly since I may have to do a lot of legwork to get this stuff made up fast.


The simplest thing I can think of right now, in the few seconds I have before I fall asleep, is a 110Vac relay - plug the coil into a power socket. On the NC contacts, wire your buzzer and a suitable battery. OK, so it doesn't have a reset switch - you have to disconnect the battery to stop it buzzing. I might think of something better later.

PS. 40dB is very quiet. You may want something more like 90dB to wake you up in the night (seriously).

Someone Electro

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This circut charges the batery wen it has power and wen not it beeps

Wire parallel a light so you can see the device at night (not neseseraly)

Put a switch on the beper so that you can thurn it off


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