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 off delay timer?
A delay timer that immediately closes contacts when the control coil is energized, then waits for a predetermined amount of time to open them after power is removed from the coil.
Learn more about off delay timer in the class "Deceleration Methods 380" below.
Deceleration Methods 380
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
Deceleration Methods 380
Description
This class describes the various methods used to cause motor deceleration. It explains the situations where braking is needed and shows how braking is accomplished.
Prerequisites
550255
Difficulty
Advanced
Number of Lessons
14
Take a Free Trial Class!
Contact Me!
Class Outline
Class Objectives
Objectives
What Is Deceleration?
Coasting
Reasons to Brake a Motor
Deceleration Methods
Friction Braking
Friction Braking Methods
Electric Braking
Electric Braking Methods
Dynamic Braking
Dynamic Braking Methods
Plugging
Brake Maintenance
Summary
Define deceleration.
Describe coasting.
Describe the reasons to brake a motor.
Identify common deceleration methods.
Describe friction braking.
Describe common friction braking methods.
Describe electric braking.
Describe electric braking methods.
Describe dynamic braking.
Describe dynamic braking methods.
Describe plugging.
Describe common brake maintenance practices.
Class Vocabulary
Term
Definition
accelerate
To increase the rate of speed.
brake fade
A reduction in braking effectiveness caused by excessive heat and wearing of components.
brake fluid
Hydraulic fluid used in some brake designs. When disk brakes are applied, the hydraulic fluid is sent through the brake lines to the pressure plate or caliper to apply pressure to the rotor and slow or stop motion.
brake pad
The anti-friction material that lines plates and calipers used in disk brakes. Brake pads help to reduce heat and increase the life span of braking elements.
brake shoe
Anti-friction material that lines metal plates in brakes. Shoes help to reduce heat and increase the life span of braking elements.
braking
Applying some force to cause deceleration.
bridge rectifier
A type of full-wave rectifier with four diodes that converts both the positive and negative cycles of AC voltage to DC.
brushes
Sliding electrical contacts used to provide a connection between the armature and the external circuit.
caliper
A component in disk brakes that holds brake pads and straddles the rotor, pressing against it when the brake is applied to slow and stop motion. Disk brakes with calipers do not create as much heat as brakes with a friction plate.
coasting
The natural rate of deceleration of a motor when the power is removed. Coasting is the simplest deceleration method.
contaminant
Damaging foreign material such as dirt or shop debris that causes wear to machine components.
counter emf
The voltage induced in the armature of a DC motor that opposes the applied voltage and limits armature current.
counter torque
A rotational force that opposes the directional force of torque. Plugging and dynamic braking apply counter torque to a rotor.
DC injection braking
Another name for electric braking. Direct current is injected into the system to create constant pole magnetic fields.
decelerate
To decrease the rate of speed.
disk brake
A friction brake that stops motion when a stationary element is pressed against a rotating disk. Disk brakes are commonly used in automobiles and in some industrial machinery, especially in older machines.
dynamic brake
A type of brake that reconnects a motor as a generator. This converts the mechanical motion into electrical energy.
dynamic braking
A motor deceleration method that reconnects a motor as a generator. This converts the mechanical motion into electrical energy.
electric brake
A non-contact brake design actuated when an electric current charges a coil that acts as an electromagnet. Electric brakes are widely used in automated machinery and provide a high cycling rate.
electric braking
A motor deceleration method that uses DC to create a constant magnetic field.
friction
The resistance to motion between the contact surfaces of two objects. Friction generates heat and increases the wear between components but is the key to providing mechanical braking force.
friction brake
A brake that engages when two surfaces press together and transfer energy through friction. Friction brakes are the most common type available.
friction plate
A stationary disk used in disk brakes to apply pressure to the rotor and slow and stop motion.
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.
mechanical interlock
Arranging forward and reverse contacts so that it is physically impossible for both sets of contacts to close at the same time.
off delay timer
A delay timer that immediately closes contacts when the control coil is energized, then waits for a predetermined amount of time to open them after power is removed from the coil.
piston
A piece of metal that moves up and down inside a hollow cylinder in response to a pressure change in pneumatic and hydraulic systems. Pistons may be used to transfer motion to brake components.
plugging
A motor deceleration method that reverses the motor connections so that the motor develops a strong counter torque.
plugging switch
A mechanical switch that opens and closes contacts when a motor reaches a set speed. Plugging switches keep the load from reversing once the counter torque has stopped the load.
rotor
The driven, rotating disk in a disk brake that is stopped when pressure is applied by a stationary friction plate or by a caliper.
service factor
A measure of the amount of overload a motor can reasonably handle. A service factor of 1.35, or 35% over the rated horsepower without overheating, is required for a motor to be plugged for regular braking.