Does anyone know how to calculate UPS Power assuming I have server with 650 of watt.
Best Answer
Math is nice and all, but if you'd rather pick and choose from a list of equipment you might consider using the very nice UPS sizing tool from APC: http://www.apc.com/tools/ups_selector
I don't always purchase APC UPSs, but their selector tool can "do the math" for you and gives you some numbers in the end that can be applied to any UPS manufacturer's offerings (as well as, of course, some suggested APC products).
If you really want to know how much current your device is using I'd recommend using a clamp-on meter to test it. (You can certainly use something like a "Kill-a-watt" if you have it, too. The clamp on meters are nice because you don't have to disconnect anything.)
Having had some 'discussions' with the inspector that comes around our offices once a year to make sure we're not being bad, I have a better idea as to what code says about this. Paraphrased from said inspector:
Thou shalt not plug a power-strip into another power-strip Nor any multi-outlet device into another multi-outlet device, for it is a fire-hazard, and therefore bad.
Thy UPS counts as a multi-outlet device Therefore thou shalt not plug thy UPS into thy power strip, nor plug thy power-strip into thy UPS, for it is a fire-hazard, and therefore bad.
A multi-outlet device shall only be permitted to be attached to another multi-outlet device if it is hard-wired into the first multi-outlet device Which renders it a single multi-outlet device.
The inspector wasn't kind enough to elucidate what, exactly, constitutes the 'fire-hazard'. We get dinged on the power-strip in power-strip commandment every other year or so. This necessitated the purchase of a bunch of long-tail power-strips (power strips on a 15' cord), and a few long extension cords with 3 outlets on the ends of them.
Edit: Regarding rackmount UPS's and PDU's. I believe they're OK so long as the PDU plugs into a locking outlet of some kind, such as an L5-20 or L5-30.
Best Answer
Math is nice and all, but if you'd rather pick and choose from a list of equipment you might consider using the very nice UPS sizing tool from APC: http://www.apc.com/tools/ups_selector
I don't always purchase APC UPSs, but their selector tool can "do the math" for you and gives you some numbers in the end that can be applied to any UPS manufacturer's offerings (as well as, of course, some suggested APC products).
If you really want to know how much current your device is using I'd recommend using a clamp-on meter to test it. (You can certainly use something like a "Kill-a-watt" if you have it, too. The clamp on meters are nice because you don't have to disconnect anything.)