Chapter 16 Electric Motors
Capacitor Motor
Single phase AC motor that includes a capacitor in addition to the running and starting windings.
Calculating Torque
T = F * R
Temperature Rise
The difference between a motor's winding temperature when running and the ambient temperature.
Slip
The difference between the synchronous speed and actual speed of a motor.
Motor Torque
The force that produces or tends to produce rotation in a motor.
Breakdown Torque
The maximum torque a motor can produce without an abrupt reduction in motor speed.
Line Frequency
The number of cycles of supplied voltage per second.
Power
The rate of doing work or using energy.
Rotor
The rotating part of an AC motor.
Stator
The stationary part of an AC motor.
Ambient Temperature
The temperature of the air surrounding a piece of equipment.
Synchronous Speed
The theoretical speed of a motor based on the motor's number of poles and the line frequency.
Locked Rotor Torque
The torque a motor produces when the rotor is stationary and full power is applied to the motor.
Full-Load Torque
The torque required to bring a load up to its rated speed.
Pull-Up Torque
The torque required to bring a load up to its rated speed.
Starting Torque
The torque required to start a motor.
Calculating Work Produced
W = D * F
Torque
is the force that causes an object to rotate.
Shunt Motor
A DC Motor that has the field connected in parallel with the armature.
DC-Permanent-Magnet Motor
A DC motor that has only armature connections and no field connections.
DC Series Motor
A DC motor that has the series field coils connected in series with the armature.
DC Compound Motor
A DC motor that has the series field connected in series with armature and the shunt field connected in parallel with the series field and armature.
Capacitor-Start-and-Run Motor
A capacitor motor that has high- and low-value capacitors connected in parallel with each other and in series with the starting winding to provide a very high starting torque.
Capacitor-Run Motor
A capacitor motor that has the starting winding and capacitor connected in series at all times.
Motor Effenciency
A measure of the effectiveness with which a motor converts electrical energy to mechanical energy.
Dual Voltage Split Phase Motor
A motor that can be connected to either of two voltages.
Induction Motor
A motor that has no physical electrical connection to the rotor.
Dual-Voltage Motor
A motor that operates at more than one voltage level.
Single-Voltage Motor
A motor that operates at only one voltage level.
Electric Motor
A rotating output device that converts electrical power into a rotating, mechanical force.
Split-Phase Motor
A single-phase AC motor that includes a run winding an a resistive start winding that creates a phase-shift for starting
Thermal Overload Switch
A switch that operates its contacts when a preset temperature is reached.
Watt
A unit of measurement equal to the power produced by a current of 1 A across a potential difference of 1 V.
Horsepower
A unit of power equal to 746W or 33,000 lb-ft per minute.
Capacitor
An electric device designed to store electrical energy by means of an electrostatic field.
Force
Any cause that changes the position, motion, direction, or shape of an object.
Resistance
Any force that tends to hinder the movement of an object.
Work
Is applying a force over a distance.
