UPS for iMac 21,5" ?

Hello everyone,

I need your help/advice, I've been trying to buy a new UPS for my iMac 21,5" and I'm at a loss. I can't decide what's the "VA" necessary for my machine. I'm planning to plug my router , plus an external hard disk drive of 500GB on the UPS, so I was wondering if a UPS 550VA is enough for my needs.

This is what I was thinking of :

APC Power-Saving Back-UPS ES 8 Outlet 550VA 230V CEE 7/7

Thanks!

An UPS serves two purposes: Prevent data loss in the event of a power shutdown, and smooth out the AC (remove ripple, prevent line spikes) to your machine.

With that said, I would look for an UPS that provides at least 750 VA and is compatible with OS X. You want compatibility so that your iMac will be able to effect a controlled shutdown when the AC mains are shut off.

Regards.

For your purposes, Watts = VA * .6. That won't pass in an electronics examination, but is close enough for estimating a UPS. So that UPS is about 300 watts. Or a little more.

Your IMac will take most of that capacity (about 250 watts). The router and USB drive will have trivial current consumptions - you can tell from the data on the wall transformers.

You will be very close to maxing out with that model. As chscag stated, you need to move up a notch to at least a 750. Also, remember that the VA number on a UPS is to indicate maximum output wattage, not runtime. You can have a UPS that will keep your Mac going for a only few minutes, or a model with the same VA that will run it for days. Those are two different ratings for a UPS that you need to decide on.

You have noticed that the UPS that you quoted is for 230 volt input? Very unusual input voltage for the average Mac user.