On 2/10/2012 1:57 PM, Gareth Magennis wrote:


"mike" wrote in message
...
On 2/10/2012 11:22 AM, Gareth Magennis wrote:


It's not unusual for a transformer to draw some amps when unloaded.
That's what inductors do. The current should be out of phase with the
voltage.
What you care about is POWER. Measure the RMS power consumed by the
transformer. That's what counts.




How might you do that?
(I don't have a power meter kicking around)

Sure you do. It's on the outside of your house and goes
round and round...They send you a bill every month.
My base load is 200W, so an additional 300W would be
easy to see.
The newer ones simulate round and round
with an lcd display and have a flashing IR led that can
be used to measure actual power quite accurately.
If you have an old Palm III vintage PDA, I can send you
a program that lets you point the IR window at your power
meter and graph consumption...but a stopwatch counting
the display works as well.

It's best to turn off everything you can to reduce the base
load and improve the precision of your measurement with and
without the transformer connected.

If you wanna spend a few bucks, the P3 Kill A Watt meters
are very handy in this application.



Er, not everyone lives in North America. I happen to live in the UK.
Sorry for your loss.

Tell me again how you might measure the power consumption of a transformer.

Not sure how repeating myself helps, but here goes.
I'd plug it into a Kill A Watt meter. That's how I got the other
experimental
results I mentioned in this thread.

I also disclosed several other techniques.

If you would read the parts you snipped, I also gave you several other
ways to estimate the power consumption of a transformer.

If you don't have a readable utility meter or a stopwatch or a
light bulb or a voltmeter or a scale or a thermometer or a hand, you
probably
should look elsewhere for advice. I'm all out.

Wait.....
I think I figured out how to do it with a used tea bag, the chime
from Big Ben and a plate of fish and chips.
Nope, you're still gonna need the hand.


Gareth.