Contact Us
|
Support
English (US)
Deutsch (German)
Español (Spanish)
中国 (Simp. Chinese)
First-Time Registration
Home
Overview
Class List
Download Brochure
Free Trial Class
Take a Tour!
Price List
Contact Me
Contact Us
Solutions
Small and Medium Size Manufacturers
Large and Enterprise Manufacturers
Educational Institutions
Industrial Distributors
Individual Students
Training ROI
Latin America
Programs by Job Title
NIMS
Products
Classes
Assessments Tests
BookStore
Custom Training
Class List
Search Class Catalog
Newest Classes
Printable Class List
Clases en español
Future Classes
By Job Title
Customers
Student Login
Administrator Login
First-Time Registration
Take Assessment Test
Community
Support
Company
About Us
Partners
Press Releases
Newsletter
Contact Us
Careers
Blog
Home
>
Class Catalog
>
Class Overview
E-Mail Page
Print Page
Comments
What is the definition of percent slip?
The difference between a motor's synchronous speed and its speed at full load. Percent slip is a way to measure the speed performance of an induction motor.
Learn more about percent slip in the class "Acceleration Methods 385" below.
Acceleration Methods 385
Motor Controls Department
Class Information
Tooling U classes are offered at the beginner, intermediate, and advanced levels.
The typical class consists of 12 to 25 lessons and typically requires at least two hours of instruction time.
Class Name
Acceleration Methods 385
Description
This class will describe the factors involved with motor acceleration and how they relate to each other. It will also explain how speed and acceleration are controlled in various types of electric motors.
Prerequisites
550255
Difficulty
Advanced
Number of Lessons
14
Take a Free Trial Class!
Contact Me!
Class Outline
Class Objectives
Objectives
Motor Acceleration
Motor Torque
Locked Rotor Torque
Pull Up Torque
Breakdown Torque
Full Load Torque
Horsepower
Motor Loads
NEMA Design
Controlling Acceleration
DC Motor Speed Control
AC Motor Speed Control
Summary
Describe motor acceleration.
Describe motor torque.
Define locked rotor torque.
Define pull up torque.
Define breakdown torque.
Define full load torque.
Describe horsepower.
Describe different types of motor loads.
Describe NEMA motor design characteristics.
Describe methods of controlling motor acceleration.
Describe speed control in DC motors.
Describe speed control in AC motors.
Class Vocabulary
Term
Definition
accelerating torque
Another name for pull up torque. It is called accelerating torque because this is the moment at which speed transitions from starting speed to full speed.
acceleration
The rate at which speed increases.
base speed
The speed (in rpm) at which the motor runs with full-line voltage applied to the armature and the field.
breakdown torque
The maximum torque a motor can produce without abruptly losing motor speed.
constant horsepower/variable torque
A load that requires high torque at low speeds and low torque at high speeds. Horsepower remains constant as speed and torque are inversely proportional.
constant torque/variable horsepower
A load that requires a constant torque throughout acceleration. If the load needs to move faster, the horsepower is increased.
copper loss
A power loss due to current flowing through wire. The lost power is converted into heat.
counter emf
The voltage induced in the armature of a DC motor that opposes the applied voltage and limits armature current.
frequency
A measurement of the number of complete AC cycles that occurs in one second. Frequency is measured in Hertz (Hz).
friction
The resistance to motion between the contact surfaces of two objects. Friction generates heat and increases the wear between components.
full load torque
The torque needed to produce the rated power at the full speed of the motor.
horsepower
A unit of power used to describe machine strength. One horsepower equals 33,000 ft-lbs of work per minute, or 746 watts.
inertia
The tendency of an object to stay in its state of rest or motion until acted on by an external force. Torque and braking must overcome inertia to accelerate or decelerate a motor.
inrush current
The initial surge of current into the windings. Inrush current can be up to ten times higher than the continuously needed current because there is low initial resistance.
locked rotor torque
The torque that a motor produces when full power is supplied to the motor and the rotor is not yet moving.
NEMA
The National Electrical Manufacturers Association. Motor nameplates carry NEMA letter designations that indicate the design characteristics of the motor.
percent slip
The difference between a motor's synchronous speed and its speed at full load. Percent slip is a way to measure the speed performance of an induction motor.
pull up torque
The torque needed to cause a load to reach its full rated speed.
rheostat
A continuously variable electrical resistor used to regulate current.
speed control
The external means of varying the speed of a motor under any type of load.
speed regulation
The ability of a motor to maintain its speed when a load is applied. A motor's speed regulation is fixed based on its design.
starting torque
Another name for locked rotor torque. It can be called starting torque because it is the torque applied by the motor at startup.
synchronous speed
The speed of the rotating magnetic field of an AC induction motor.
torque
A force that produces rotation. Torque is measured in pounds-feet in the English system and Newton meters in the metric system.
variable frequency drive
A device that converts incoming 60Hz AC power into other desired frequencies to allow for AC motor speed control.
variable torque/variable horsepower
A load in which both torque and horsepower requirements can change depending on the needed speed.
watt
A unit used to measure power. 746 watts equals one horsepower.