The Difference Between DC and AC Driven Electric Motors
Author: Cin Rupp
When it comes to electric motors, many people do not know the difference between AC and DC electric motors. In order to understand the difference, one must first be made aware of the fact that an electric motor is a machine that is used to convert electrical energy into mechanical energy. Our modern society depends upon these motors as we use them in our computer printers, machine tools, automobiles, vacuum cleaners, water pumping stations and much, much more.
Even though the majority of electric motor manufacturers are moving away from direct current motors, DC machines are still powering a lot of machinery in heavy industrial settings. DC motors are still being used to power surface mining excavators, mine hoists, massive metal rolling mills and many more types of industrial applications and direct current is expected to continue delivering the power in many types of production work for many years into the future.
Alternating current or AC motors work well in many different types of situations. This type of motor was first made back in 1882 when a two phase induction motor was designed. There are two basic types of alternating current motors, depending upon the type of rotor employed. One is the synchronous motor and the second is the induction motor. With the first type, the motor rotates exactly at the supply frequency and with the induction AC motor, it runs slightly slower than the supply frequency. Alternating current motors are ideal for use with equipment that is difficult to start because this type of motor is tremendously powerful. The name 'alternating power' was assigned to this type of motor because AC motors alternate in power. In other words, the amount of power expended by an alternating motor is determined by the amount of power required to run the given machine or equipment.
AC electric motors are used the world over in homes, businesses and industrial settings. An alternating current motor can be a part of a fan or a pump or it can be connected to some other form of mechanical equipment such as a conveyor belt or a mixer. Some mechanical applications require just one AC motor while others may need several motors in order to operate. The torque capabilities of an AC motor are taken into consideration to determine whether it can meet the torque requirements of the application's load when deciding on what size of motor to use.
Article Source: http://www.articlesbase.com/electronics-articles/the-difference-between-dc-and-ac-driven-electric-motors-2947082.html
About the Author
This article is written by Cin Rupp to provide information on electric motors with specific stress on AC motors and DC motors for further information have a look at flanderselectric.com
Some electric motors have a governor device on them to automatically switch from the starter capacitor to all ac. Those switches can go bad and will cause this type of problem.
If it is the reset switch, or any other type of switch, good luck in finding one. I have these switch issues at work and can not find them. Had to replace the whole motor.
Good Luck
Three or four wire system
Measure phase A to B
Measure phase C to B
Measure phase A to C
Measure phase A to Ground
Measure phase B to Ground
Measure phase C to Ground
AB, AC, and BC should have close to equal resistance.
A,B, and C to ground should be in the Mega ohms or Infinity
Why doesn’t my AC electric motor not start when I plug it in?
I have an air compressor AC motor and when I plug it in, it acts like it’s not getting any power at all. My thoughts are the the reset switch on it is broken. Could that be it, or could the windings on the motor be bad?
I’ve already replaced the start and run capacitors, so those work. The reset switch just seems to be in bad condition. If so, is the reset switch a special kinda one? And where could I get one?
There are many different types of AC motors. Very few of them have permanent magnets inside. An AC motor with permanent magnets is called a permanent magnet synchronous motor. A brushless DC motor is essentially the same thing as a permanent magnet synchronous motor. A brushless DC motor has an electronic commutator that can be an external controller or circuitry inside the motor. The electronic commutator converts DC power to a square wave approximation of AC.
how to detect 3 phase AC electric motor burned?
if a 3 phase AC electric motor is burned ?how to detect it.
Does an AC electric motor have a permanent magnet inside?
I’m going to start building an electric car soon, and i’m trying to understand everything about ac and dc motors, how they work, and which application would be best.
AC is alternating current. It varies with time, as a sine wave. It’s values vary instantaneously. In AC the electrons change direction.
DC is direct current, and it remains steady. In DC the electrons will carry on flowing around the circuit without changing direction.
This site will help you with the details of an AC electric motor:
http://www.coolmagnetman.com/magacmot.htm
How to control the speed of a Electric AC motor?
I am looking for a device that would allow me to control how fast a AC motor spins. I am using a 110v AC motor that came off a air compressor. Can anyone help?
A 110V motor must be a single-phase motor. With a three-phase motor, you can control the speed with a variable frequency drive (VFD). VFDs for three-phase motors are widely available. There are some VFDs sold for single-phase motors, but they are recommended only for permanent split capacitor (PSC) motors and shaded pole motors and only for fan and centrifugal pump loads.
You don’t need 3-phase power, you can get a VFD that will convert single-phase power to 3-phase.
http://www.automationdirect.com/adc/Shopping/Catalog/Drives
Here is a VFD for a single-phase motor:
http://www.anaconsystems.com/text/eagle1.html
A light dimmer might work with a shaded pole motor driving a fan.
How does and AC Electric Motor work?
Can you please explain this with a lot of detail based on magnetic field, and currents, force, and possibly voltage. I keep getting confused between a DC and AC.
Thank You so Much!