H - Terms
HEAT EXCHANGER
A device which will transfer the heat from inside the motor to another medium, through a radiator type heat exchanger.
HERTZ (HZ)
One cycle per second (as in 60 Hz. which is 60 cycles per second).
HORSEPOWER
The measure of rate of work. One horsepower is equivalent to lifting 33,000 pounds to a height of one foot in one minute. The horsepower of a motor is expressed as a function of torque and rpm. For motors the following approximate formula may be used:
where HP = horsepower, T = torque (in. lb.ft.), and RPM = revolutions per minute.
HYSTERESIS LOSS
The resistance offered by materials to becoming magnetized (magnetic orientation of molecular structure) results in energy being expended and corresponding loss. Hysteresis loss in a magnetic circuit is the energy expended to magnetize and demagnetize the core.