AC Motor speed & direction control
AC Motor speed & direction control
(OP)
Please, could some one explain how the Wash Machine's AC Motor ( with capacitor on it )speed and direction controlled ?
During the wash cycle, the motor rotates back an forth at low speed, while at spin cycle rotates at very high speed.
My question is how during the wash cycle the motor's speed is reduced and the rotation direction is reversed?
During the wash cycle, the motor rotates back an forth at low speed, while at spin cycle rotates at very high speed.
My question is how during the wash cycle the motor's speed is reduced and the rotation direction is reversed?





RE: AC Motor speed & direction control
The speed is controlled by reconnecting the windings to provide more or less poles.
The direction is controlled by reversing the polarity of the starting winding.
yours
RE: AC Motor speed & direction control
thread237-172357
JRaef.com
"Engineers like to solve problems. If there are no problems handily available, they will create their own problems." Scott Adams
For the best use of Eng-Tips, please click here -> FAQ731-376
RE: AC Motor speed & direction control
Zacky didn't specify really which style. In the top loaders the back and forth is created in a transmission (Agitation). And just as waross sez it is a fixed AC motor that turns one way to to agitate and pump water(which is valved to recirculate thru a strainer) and then turns the other way to spin and pump water(which is valved to drain). This style uses an AC motor and they just hook up the start part of the winding differently before starting to reverse it.
All front loaders use BLDC and they actually control the motor speed and direction via PWM. The speeds are profiled with acceleration curves etc..
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: AC Motor speed & direction control
Also I noticed in the machine schematic a coil named " BRAKE/CLUTCH" what that coil for ?
RE: AC Motor speed & direction control
The clutch/brake is to stop the 120lbs of rotating metal/wet clothes at the end of spins. Partly for safety and partly because there will be resonances in the area between wash speeds and reaching spin speed that will send a washing machine around the room like a super-ball. They want to force a rapid transition thru those regions.
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: AC Motor speed & direction control
RE: AC Motor speed & direction control
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: AC Motor speed & direction control
BTW folks, this is hardly a professional engineering issue, be prepared for the inevitable red flag. I won't do it, but there are those more intent on keeping this forum clear of homeowner related postings.
RE: AC Motor speed & direction control
respectfully
RE: AC Motor speed & direction control
Now I disconected one of the wires going to "BRAKE/CLUTCH" solenoid and now it is de-energized and the machine spins BUT AT LOW SPEED.
Is the problem the electronic control unit?
RE: AC Motor speed & direction control
yours
RE: AC Motor speed & direction control
http://fixitnow.com/faq.htm
http://www.washerhelp.co.uk/diy-repair-help.html
RE: AC Motor speed & direction control
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com