30 Jan
2011
30 Jan
'11
12:49 a.m.
Can some of you EE types talk about the (in)efficiency of stepdown
transformers? Like say a 2000 watt 220 to 110 transformer. How bad
are they?
brian
1:54 a.m.
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9:44 a.m.
From: brianlanning at gmail.com
Can some of you EE types talk about the (in)efficiency of stepdown
transformers? Like say a 2000 watt 220 to 110 transformer. How bad
are they?
brian
Transformers have several sources of loss. One is core
eddy currents. This is controlled by the size of the wire.
Another is from the resistance of the wire. The last
is a combination of the primary wire resistance and
the phase current. This is related to the inductance
of the windings.
Dwight
10:24 a.m.
On Sunday, January 30, 2011, Brian Lanning wrote:
Can some of you EE types talk about the
(in)efficiency of stepdown
transformers? Like say a 2000 watt 220 to 110 transformer. How bad
are they?
More or less, what Will said.
Typical is 95% efficiency.
At low loadings, they'll have a crappy power factor (as they'll have a
relatively high inductive load compared to real power being used), but
unless you're a large-scale energy user (ie, use Megawatts of power),
you don't care, and the utility won't be billing you for anything but
the real power.
Pat
--
Purdue University Research Computing --- http://www.rcac.purdue.edu/
The Computer Refuge --- http://computer-refuge.org
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