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Spurious Response

On Wed, 4 Jul 2007 08:29:02 +0000 (UTC), (Geoffrey S.
Mendelson) wrote:

This is very common for transformers (which many people use here to operate
120 volt appliances brought in to avoid high taxes and huge markups) and
UPS's for computers, both of which are sold as being rated in WATTS,
but really are rated in VA which are 1.414 times as much.

VARS?

The transformer and the UPS are VA rated and declared devices. The
computer power supply is declared in Watts here and it is correct. If
all the outputs are loaded as rated, the input power requisite will be as
declared.

The rating on a PC power supply is its OUTPUT side DC power rating. The
amount required to make a 500 Watt DC personal computer supply put out
500 Watts will always be greater than 500 Watts on the AC Line side of
the supply. That is usually declared as well, however, and it is usually
correct from what I have seen.