Help Me Decide Between Two UPS for Mac Pro

[Bartman01]

Timeout, Bartman. There is no issue running a Mac Pro power supply on a stepped-square wave UPS for a short while.
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The sky isn't going to fall if someone with a decent power source chooses to use a stepped-square wave UPS for those rare times when they lose power.

S-

In principle I agree with you. That being said I have found a few reports like this one http://www.apc-forums.com/message.jspa?messageID=11282 where certain power supplies don't work properly with stepped wave output from a UPS.

This is what I currently use around the house:
Back-UPS XS 1000 (main computer and monitors but not a MacPro)
Back-UPS ES 500 (networking and printer)
Back-UPS XS 800 (downstairs TV/DVR/Wii)
Smart-UPS 1500 (upstairs TV/DVR/Consoles/etc)
Line-R 1250 (upstairs receiver/amps)

You can see that the only true sine-wave equipment is on the main A/V equipment, so I personally have no problems with non-sine wave equipment. I was just correcting an earlier comment I made that there were NO issues using that type of output with computers when I have found some data (including posts from APC support reps) showing that in some cases there are issues.

Edit: This post seems to indicate that the issue is really that people are running too-little UPS for the newer power supplies.

 

[monokakata]

I'm covering my Mac Pro 1,1 with an APC RS 1000, because I already had it. It works OK for short outages.

I think the general answer about wave form is that some power supplies don't like modified square waves, and some don't care -- in other words, case by case.

There's another side to wave form (as it were). Most UPSs cannot tolerate AC input from classic generators, which is not sine wave output. I've had this kind -- they trip their breakers immediately. Almost all on-demand UPSs cannot tolerate generator input.

Online (meaning that the output to the load is 100% from the inverter/batteries at all times) UPSs can tolerate generator input. With these, you get total isolation from the powerline -- nothing is passed through. They tend to be large, heavy, noisy, and expensive.

I had units from Best and Exide, and another very high quality one, now offered as Falcon. I'm talking $1000+ for some of these, but if you have to have a UPS and you have to power it from a classic generator, you have little or no choice.

The newer inverting generators put out an acceptable wave form and I'm told you can power an ordinary UPS with them.