Product Manual

Mounting: The most common motor mounts include: rigid base,
resilient base C face or D flange, and extended through bolts. (See
Chapter IV for additional details). Gear reducers are similarly base-
mounted, flange-mounted, or shaft-mounted.
National Electric Code (NEC): A safety code regarding the use of
electricity. The NEC is sponsored by the National Fire Protection
Institute. It is also used by insurance inspectors and by many govern-
ment bodies regulating building codes.
NEMA (National Electrical Manufacturers Association): A non-
profit trade organization, supported by manufacturers of electrical
apparatus and supplies in the United States. Its standards alleviate
misunderstanding and help buyers select the proper products. NEMA
standards for motors cover frame sizes and dimensions, horsepower
ratings, service factors, temperature rises and various performance
characteristics.
Open Circuit: A break in an electrical circuit that prevents normal
current flow.
Output Horsepower: The amount of horsepower available at the out-
put shaft of a gear reducer. Output horsepower is always less than the
input horsepower due to the efficiency of the reducer.
Output Shaft: The shaft of a speed reducer assembly that is connected
to the load. This may also be called the drive shaft or the slow speed
shaft.
Overhung Load: A force applied at right angles to a shaft beyond the
shaft’s outermost bearing. This shaft-bending load must be supported
by the bearing.
Phase: The number of individual voltages applied to an AC motor. A
single-phase motor has one voltage in the shape of a sine wave applied
to it. A three-phase motor has three individual voltages applied to it.
The three phases are at 120 degrees with respect to each other so
that peaks of voltage occur at even time intervals to balance the power
received and delivered by the motor throughout its 360 degrees of
rotation.
Plugging: A method of braking a motor that involves applying partial or
full voltage in reverse to bring the motor to zero speed.
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