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Old 04-22-2009, 06:01 PM
cernst cernst is offline
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Quote:
Originally Posted by darth vader View Post
I'm considering 230V (Europe).

You have a point: Watt is not Volt x Ampere.

But if the datasheet gives me a consumption of 300 Watt, I would assume 300/0.8 = 375 VA which is not a big difference.


This is a real example of a device we are going to install:
The datasheets gives me this info:

"Input voltage: 100 to 240VAC,
47 to 63 HZ, 3A
Output Power: 250W."


3Ax240VAC= 720 VA whichis much higher than the 250 W
okay, so it'll pull 3 amps when running at 100 volts...300 watt. In the US, most commercial 200+ volts is setup in a Wye setup, which generally comes out around 208v. With 208v, you'll be pulling about 1.4 amps.

If you are looking to size a UPS to a load, look at your watts. Most UPS manufacturers will post the load rating in volt-amps and/or watts to make it easier on the user. For example, looking at APC's 750va lineup, we have the SUA750 and the SUA750RM2U. Both are 750va UPS units. Both use the exact same batteries (just in different physical configuration). But looking at the tech specs, the SUA750 allows for 20 extra watts over the SUA750RM2U.
APC Smart-UPS 750VA USB & Serial 120V
APC Smart-UPS 750VA USB & Serial RM 2U 120V
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