Power consumption of Mac / UPS
 

Hello,

When trying to size a UPS unit for my Mac and monitor, I noticed that my new 867 Mac is rated at 8 amps. !? My 1.7 gig PC is rated at 2 amps. I guess I am misunderstanding the Mac's rating.

In anycase, I happened to have a good Best Fortress 1425 Va UPS on hand, so I figured I'd try it out with the Mac and see how big the explosion would be.

It worked out fine! The 8 amp rating of the Mac is apparently not realistic. 8 amps would convert to about 960 Va (volt/amps)... and my 21" Sony G520 monitor is rated at 2 amps which makes sense (240 Va). So, I thought I was going to be pulling a total of 1200 Va through the 1425 Va UPS which is basically right on the line.

However, after running the Mac and monitor through the 1425 Va UPS, the usage meter of the UPS indicates that less than 50% of the UPS's capacity is being tapped, probably closer to 30% or 40%. So, the UPS is basically saying that the Mac and monitor are pulling less than 700 Va together.

Anyhow, just thought I'd post this info for anyone who may be interested in this subject. Boy, am I glad I have a UPS... power went out two times today already!

Best offers Fortress model UPS units in 750, 1050, 1425 Va sizes and up. Based on my observation here, a 750 Va might just make it for a Mac and monitor, but it might be REALLY close. I'd probably recommend at least a 1050 Va... you don't want to run these things right at the edge... also it's nice to have a little room to add an external hard-drive or cd burner etc onto it. I'm real happy with the 1425 Va.

I had gotten the 1425 Va Fortress really cheap at CDW a few months ago.

-imp

Re: Power consumption of Mac / UPS
 

I'd just like to add that if you get a UPS (essential), get a good quality one with strong power filtering also.
Make sure you only run essential devices off it, ie. Mac/PC & Monitor and related Hard drives.
You only need enough power in it to shut it down safely, (unless it's a data server in which case you shouldn't be using it for audio).
Only load the UPS to 60%. much more than this and you'll burn it out or at least dramatically reduce the life of it.
Try to get one with user serviceable batteries too. APC has some like this.
Finally, when considering the cost of the UPS, how valuable is your work and productivity?