27 May
2009
27 May
'09
3:35 p.m.
Jerome H. Fine wrote:
I would like to buy a power supply that is about
double the usual
capacity that I will need, but I am wondering how this choice
might affect the UPS up time when the street power fails?
A switching power supply
does become less efficient at low load. A
switcher that is 80% efficient at rated load might only be 60% efficient
at half load. However, there's no general way to determine the
efficiencies for a particular supply except to check the specs (which
often don't have that information), or to measure it.
Eric