Reversible AC motors

[KillRoad..]

Hello, can someone please help me.

 

 

So.. I need to build circuit with two reversible motors.. I need to make something like reversible fan system, one fan goes forwards, other backwards.. ofter couple hours they reverses.. I have AC 220V supply. question is.. how can i make this up easier ? The simplest solution is The best. All needed to be automatized my thought is use timing relay, inverters ?

 

What kind of motors i need to use ? reversible AC motors would be The best chose i think.. If i use DC motors that would be messy, needed to change supply from AC to DC, yes, its not so hard, using diode bridge and stuff, but then voltage drops.. and again it's problem for me.. that's why i think AC would be better, no supply change.

 

Easiest way to put up circuit which can make reverse two motors after few hours ? All automatized, no buttons forward, backwards..

Can it be done ?

 

I would be very grateful if some one helped me with this my problem..

[Spyman]

Since this is posted in homework my guess is the fans are going to be small. I suggest DC fans with polarity change.

[KillRoad..]

Since this is posted in homework my guess is the fans are going to be small. I suggest DC fans with polarity change.

 

I need to change old one motor.

Old one's parameters:

 

Phase 1

Type of viltage AC

Nominal voltage in V 230

Frequency in Hz 50

Speed in min-1 2750

Power input in W 47

Air flow in m3/h 202

Sound power level in B 6,6

[Spyman]

Yes, your old motor is not electrically reversible.

[TonyMcC]

It is quite possible to have reversible ac motors. One type is similar to a dc motor, except the magnetic field is produced by an alternating magnetic field instead of a permanent magnet. You can work out how to reverse such a motor.

Another type uses a capacitor to produce phase shift which means the rotor can be fed with an overall rotating magnetic field which a sqirrel cage can follow. You can work out how the field rotation could be reversed.

If all else fails then it is possible to buy reversible ac motors. http://www.orientalmotor.com/products/ac-motors/

[Spyman]

It is quite possible to have reversible ac motors.

Yes, but the little 1-phase fan the OP already has is certainly not likely one of those and I don't think it's possible to modify it easily either.

[TonyMcC]

Yes, but the little 1-phase fan the OP already has is certainly not likely one of those and I don't think it's possible to modify it easily either.

I agree with you. In fact I wouldn't really expect anyone to convert any motor designed to rotate in one direction into a reversible motor. However, as this was a homework question, I thought it not a bad idea to say that such a thing was (theoretically) possible. I then mentioned that if all else fails you can buy a reversible motor. I hoped that "if all else fails" would be taken as "having thought about it".