Product Manual

Insulation: In motors, classified by maximum allowable operating
temperature. NEMA classifications include: Class A = 105°C, Class B =
130°C, Class F = 155°C and Class H = 180°C.
Input Horsepower: The power applied to the input shaft of a gear
reducer. The input horsepower rating of a reducer is the maximum
horsepower the reducer can safely handle.
Integral Horsepower Motor: A motor rated one horsepower or larger
at 1800 RPM. By NEMA definitions, this is any motor having a three digit
frame number, for example, 143T.
Inverter: An electronic device that changes direct current to alternating
current; in common usage, an AC drive.
Kilowatt: A unit of power equal to 1000 watts and approximately equal
to 1.34 horsepower.
Load: The work required of a motor to drive attached equipment.
Expressed in horsepower or torque at a certain motor speed.
Locked Rotor Current: Measured current with the rotor locked and with
rated voltage and frequency applied to the motor.
Locked Rotor Torque: Measured torque with the rotor locked and with
rated voltage and frequency applied to the motor.
Magnetic Polarity: Distinguishes the location of north and south poles
of a magnet. Magnetic lines of force emanate from the north pole of a
magnet and terminate at the south pole.
Mechanical Rating: The maximum power or torque a gear reducer can
transmit. Many industrial reducers have a safety margin equal to 200%
or more of their mechanical rating, allowing momentary overloads dur-
ing start-up or other transient overloads.
Motor Types: Classified by operating characteristics and/or type of
power required. The AC induction motor is the most common. There are
several kinds of AC (alternating current) induction motors, including, for
single-phase operation: shaded pole, permanent split capacitor (PSC),
split phase, capacitor start/induction run and capacitor start/capacitor
run. Polyphase or three-phase motors are used in larger applications.
Direct current (DC) motors are also common in industry as are gear-
motors, brakemotors and other types. (See Chapter III for additional
details).
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