Look, Dido.... a quick inspection of NEMA and IEC specs say that most
motors are 'designed' for +/- 10 percent... that's all.
Anything more or less and the motor is running so out of sync with the
line that it builds heat rapidly. AC and motor theory are as clear as
they can be...
Heat kills motors... maybe not immediately but in short order.
Shaded pole motors are crap.. and if they're in anything you depend on
you ought to throw them away and use real motors. They're great in wall
The back-emf argument is also bullshit. Back EMF is 'out-of-phase' and
counteracts the inputted energy. It hurts you.. not helps.
As with all things in the genre... energy IN equals energy OUT less
losses. If you put less energy IN... things don't work as designed.
Anything may work for a while... but not all that long. Science catches
up sooner or later.
therin lies the huge problem Jake.
From all this "stuff" I've been reading lately, the russians are so
much further ahead of Western technology for one simple reason:
They are not locked into the dogma of Western taught thermodyamicis
research US Patent # 6,362,718 granted on March 26, 2002
now you may not believe a ufo crash landed in roswell nm, nor believe
there is an area 51 or any of that other secret bs, but if you do,
explain how a nuclear reactor on these ufo's can use element 115 to
generate the electromagnetic currents they do, WITHOUT ANY FORM OF
COOLING. There goes the laws of Western taught thermodynamics...
when we remain of the mindset that energy in=energy out minus loss, we
will never strive to achieve what other countries and civilizations
have already achieved.
Jake: read my post again I will not dwell with you on pro or cans
I posted what I work with the only thing I forgot to include that
these is only on single phase motors and dimmers that can be
use is only those that use triacs for output instead of SCRs
Back EMP reduces the voltage and hence the current.
Without back EMF (stalled motor), the lack of back EMF to "buck" that
applied votage will cause the current to be E/R which is much, much,
higher than when rotating.
How does back EMF hurt by reducing the CURRENT?
You have the EMF 'bucking' concept right but your thinking is out of
AFAIK Every run start cap motors used for fans in condensers use
overload breakers to avoid locked rotor overheating. This is required
because foreign objects like twigs, rats, snakes, etc. can get into the
box and stop the fan blades.
If a 220 VAC motor will turn with 110 VAC applied, it should be safe
This has been done many, many times.
Some technicians do not understand the safety built into the motors.
As an additional safety, a second lower Amp fuse may be added.
Yes, about as dumb as the people who design and make the motors;
I guess that you can't trust their words either.
"At the same time torque is being produced, the conductors are moving
in a magnetic field and generating a voltage. This voltage is in
opposition to the voltage that causes current flow through the
conductor and is referred to as a countervoltage or back EMF. The value
of current flowing through the armature is dependent upon the
DIFFERENCE between the applied voltage and the countervoltage."
The countervoltage or back EMF is opposite the applied voltage and it
"bucks" or reduces it. For example: If the applied voltage is 220
VAC and the back
EMF is 70 VAC, the motor appear to see only 150 VAC.
The result is the equivalent of increasing the total impedence and thus
reduces the current that
would flow if there was no EMF.
This is why an AC motor must spin to avoid overheating.
An automatic thermal overload protector is usually built into HVAC fan
Or, if you desire, you can always add a correctly chosen fuse to
protect your AC motor.
If you had another brain it would be lonesome.
On 13 Oct 2006 17:03:23 -0700, firstname.lastname@example.org wrote:
and argueing with you would be like fighting a sword fight and YOU
with no sword.
Honestly, Your ramblings are worse than stormy and Todd all rolled
Climb back up the skylight and shut it on your way out.
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