Rockwell Automation SP500 AC Drive Installation and Operation Manual - Manual (Page 117)

Glossary-1
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LOSSARY
accelerating torque - an increase in torque (force) generated by a motor in order to
achieve running speed.
base speed - the manufacturer’s nameplate rating at which point the motor will
develop rated horsepower at rated load and voltage.
base frequency - the motor nameplate frequency rating.
carrier frequency - the switching frequency at which an IGBT inverter bridge converts
a DC voltage into a pulse-width modulated (PWM) voltage.
constant torque - a torque (force) characteristic independent of motor speed.
current feedback - a current signal used by the regulator to control the operating
current of the drive.
decelerating torque - the torque (force) generated by the decrease in motor and load
kinetic energy which the motor and load requires to reach its final (slower) speed
condition.
drive - an electronic device that can control the speed, torque horsepower, and
direction of an AC or DC motor.
dynamic braking - a braking technique in which the kinetic energy is converted into
electrical energy and dissipated as heat energy via a resistor or other means.
frequency setpoint - the frequency value stored in memory (either by local or remote
means) within a given frequency range of the drive’s output voltage. This sets the
speed of the motor.
Hz - the abbreviation for hertz. The number of cycles per second.
IET - the abbreviation for instantaneous electronic trip. A fault condition that occurs
while the drive is running resulting in a motor coast-to-rest stop. The drive senses a
condition that could result in equipment damage and turns itself off.
input power factor - the ratio of the input inverter AC effective power to the input AC
apparent power.
inverter - a static power converter that changes DC power to AC power.
line dip - a short duration, low input voltage condition.
load torque - the motor torque required to keep the load rotating at nearly constant
speed.
NEMA - the abbreviation of the National Electrical Manufacturer’s Association.
NEMA 1 - the Type 1 enclosure defined in NEMA standards that provides protection
against dust, light indirect splashing, and accidental human contact with the electrical
circuit.
NEMA 4x - the Type 4x enclosure defined in NEMA standards that provides a degree
of protection from falling rain, splashing water, hose-directed water, and corrosion.
The Type 4x enclosure described here is for indoor use only.
NEMA 12 - the Type 12 enclosure defined in NEMA standards intended for use in
applications where it is desirable to exclude such materials as cooling oil, seepage,
dust, lint, fibers, and filings.
Glossary