3 Simple Ways to
Share What You Make

With Instructables you can share what you make with the world — and tap into an ever-growing community of creative experts.

PhotosPhotos

Share one or more photos of a project, recipe, or whatever you've made, quickly and easily.

Step by StepStep-By-Step

Share your step-by-step photos with text instructions of what you made so others can do it too!

VideoVideo

Share your how-to video. You'll need your embed code from a video site such as YouTube.

How can I build a siren when my UPS detects a power cut?

Alright, I have a large server set-up in my closet, and just recently I had a power cut, which, if not for my backups, I would have lost everything (photos, videos, documents, my soul etc.)

The problem was it was in the middle of the night, and the UPS (for some reason) didn't shut down the server when the battery drained. So I want to design a system where if the UPS is tripped, some sort of siren or flashing light goes off, so if I'm asleep, I can get up and safely power down everything.

Any ideas?

2 answers
Jun 8, 2010. 9:43 AMsteveastrouk says:
That's some bad setup if the system loses everything because of a power outage. In all the years I've run servers, none of mine have ever lost hard disk data when we've had power outages.
Jun 8, 2010. 5:08 AMRe-design says:
If it's that important, but a new ups that has the alarm and WILL shut down your system right. Then use the old ups for something else. But if you just gotta build one. But y a 12 volt relay. Power that relay by a 12 volt wall wart plugged into the same outlet as the UPS but not thru the ups. Not, plug another 12 volt wall wart into the outlet of the ups run it thru the relay contacts so that when the relay closes without power it closes the circuit to the alarm. That way when there is power the alarm is off since the relay is pulled open. When you loose power the relay relaxed and closes the switch so the ups can power the alarm and wake you up.

Pro

Get More Out of Instructables

Already have an Account?

close

All Steps Viewing
View all steps of an Instructable on the same page when you're a Pro Member.

Upgrade to Pro today!