Energy meters spin by the combination of current and voltage creating torque
on the non-ferrous disc as it tries to get out of the magnetic AC fluxes
created at 90 degrees to each other.

On resistive devices and most devices the current and power goes up as the
voltage increases. You bulb will be brighter etc..

On synchronous devices like AC motor compressors and furnace fans etc. the
speed is locked to the power line frequency. 60Hzx 2 changes x 60 sec/min /
#poles in the motor will pas the electromagnetic pole that creates the
torque and you typically get 1800 RPM. This is fairly constant, which means
the work that it puts out is constant also (constant workload) When you
lower the voltage to the motor now is has to draw more current to do the
same work and can eventually burn out by overheating from the high current.


BTW: If you have a disc or equivalent in your Electric Meter you can
determine the load of your house going through the meter at any given time
by clocking it with a stopwatch.

Look at you meter and observe the disc. You should notice a little black
mark passing on the edge of the disc every revolution. Time a couple of
these revolutions and mark the time (in seconds) down. I usually do about 60
seconds worth. There also may be fractional marks if your meter is moving
really slow and don't have an hour to wait (exag)

Also notice on the front of the nameplate of your meter there is a "disc
constant" noted as kH. This is the amount of energy (in watthours) that the
meter has measured each revolution of the disc. It will probably read
something like kH 7.2 or kH 12. This is the part that is tightly regulated
for accuracy.

Now apply it to this formula:

revs x kH x time(secs) / 3600. sec per hour

This will give you your home load in watts (power). This technique can be
useful to check the power of appliances to see where you hard earned energy
dollars are going each month by shutting off all the breakers except one and
looking for the energy pigs.

If you have a solid state kilowatthour meter on your house there will be a
blinking LED or simulated disc in LCD but the same thing will apply. Look
for a constant for the "equivalent disc revs" or LED kH.

Best of luck.



"Tim Thomson" wrote in message
...

As a matter of fact would his metor not run less with some things like his
fridge, vacuum, hair dryer, washing machine, dish washer, etc. What makes
a
power metor spin? If voltage goes up does the amp draw go down?
I would give my left nut to have a little more voltage. Switch mode power
supplies love a slightly higher voltage and often run cooler when they are
run
at max voltage.