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doublecool
August 4th, 2010, 14:50
If my computer power supply is 750watts what should my battery backup watts be

doublecool
August 4th, 2010, 16:34
I guess its a dumb question...but it got me checking

Thanks for the help

mjrhealth
August 4th, 2010, 16:54
id go for at leats a 1 KVA. This will allow for start up surge. But remember all a ups is there for is to supress mains spikes, and to give you time to shut down your pc in the event of a power outage, its not meant to run it for ever, you would need to add extra batteries etc for that. Also just because your PSU is rated at 750 Wats does not mean that your PC is actually using 750 wats, but its nice to have some overhead.

NoNewMessages
August 4th, 2010, 17:37
If my computer power supply is 750watts what should my battery backup watts be

I'm using an APC 750va/450w backup. It has kicked in a few times, generally when the winds are howling or some idiot hits a power pole and it gives me time to shut everything down safely.

The personal laser printer that I use is not plugged into the APC, as it won't handle that and everything else. The laser is on it's own wall socket and still dims some lights when it gets going...

srgalahad
August 4th, 2010, 17:51
I've used UPS's since I lived in the Arctic and won't live without them now. The 750Va rating of the PS is it's limit and it shouldn't be drawing that full time so a 750/800/1000 UPS should be sufficient.

In addition, I don't keep my monitor plugged in to the Backup side of the UPS either (hold-over from the days of CRT monitors) but it's all in easy reach (lesson learned) so if I have a blackout that looks like it will continue for more than a few secs and be worthy of a shutdown, I just unplug the monitor from the Protected side, plug into the battery backup side, do the shut down and return to normal.

LCD monitors draw less but are still a strain on the battery so best to at least power them down or do as above. No point in wasting batery power before you can get back and shut down the system. Also, think about the connected UPS systems with auto-shut-down software that senses the UPS coming online and does a proper close of programs and then the system if you tend to do critical work and have a flaky power company

Rob

mfitch
August 4th, 2010, 21:47
In addition to the notes above, I always consider the number of plugs available. The internet modem (wireless for me), wireless router and any other peripherals with their own plugs are worth protecting as well. Most can go in the surge only side as noted above.

Also note that some UPS units "massage" the power. Essentially they clean up more power problems than just sudden outages or voltage spikes. I don't know how much life this adds to a computer, but I have had nothing die since I used my APC units. The extreme sensitivity can be annoying, but it can also be adjusted.