Rockwell Automation FlexPak Plus DC Drive User Manual

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Service Factor (SF):

When used on a motor nameplate, a number which indicates how much above the

nameplate rating a motor can be loaded without causing serious degradation, (i.e. a 1.15

SF canproduce 15% greater torque thana 1.0 SF rating of the same motor).

Tachometer:

A small generator normally used as a rotational speed sensing device. Tachometers are

typically attached to the output shaft of a motor requiring close speed regulation. The

tachometer feeds its signal to a control which adjusts its input to the motor accordingly

(called closed loop feedback" control).

Thermostat:

Units applies directly to the motor's windings which senses winding temperature and may

automatically break the circuit inanoverheating situation.

Torque:

Turning force delivered by a motor or gear motor shaft, usually expressed in poundsĆfeet:
lbs.ft. = HP x 5250 / RPM = full load torque