Electrical Wiring Question

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Anonymous Poster	Electrical Wiring Question 03/20/2008 11:39 AM
	I have a situation where a small single phase 110VAC 60Hz motor was incorrectly (I believe) installed a long while back; I did not do the installation. I am certain, because the motor runs backwards and the fan unit sucks the air rather than blowing it. Perhaps I could reverse the fan blades, but I cant get to them. I know that if it were a 3 phase motor, I could reverse any 2 leads and the motor would run in the opposite direction. What could be done in my case. Obviously, I would have an electrician rewire it, but I thought that it might not be possible to correct this without replacing the motor.
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CSM Engineer Guru Join Date: Sep 2007 Location: Reno, NV (USA) Posts: 608 Good Answers: 66	#1 Re: Electrical Wiring Question 03/20/2008 12:30 PM
	Some single-phase motors are reversible and some are not. You can either run the model number with the manufacturer to find out if it a reversible model, or pull the cover off the lead housing (observing all applicable safety procedures, of course). If the motor is reversible there will be a lead diagram on the inside of the cover. If the motor is non-reversible, I'm afraid you're stuck with changing it out with a motor that has the proper rotation. Good luck! __________________ Aequam memento rebus in arduis servare mentem.
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Anonymous Poster	#4 In reply to #1 Re: Electrical Wiring Question 03/21/2008 9:55 AM
	you might try using a forward reverse switching device as in the system as is used to allow forward reverse drives in many of southbend manufacturings' small lathes. what it does is allow the user of the lathe to have a "built in" form of changing of wire connections without tearing the endbells off the motor. 'da ber
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case491 Guru Join Date: Sep 2007 Posts: 1817 Good Answers: 7	#2 Re: Electrical Wiring Question 03/20/2008 5:53 PM
	It depends on the construction of the motor itself as well if the fan is supposed to suck or blow. Some suck and some blow while others just simply "churn". Some motors are reversible and the fan should neither suck or blow as it will do both depending on the direction the motor runs. The main function of the fan is to get colder air on the motor to cool it down. Either sucking or blowing can do this so neither is necessarily wrong.
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rudy.leurs Power-User Join Date: May 2007 Location: Flanders (Belgium) Posts: 343 Good Answers: 21	#3 Re: Electrical Wiring Question 03/21/2008 5:43 AM
	If you dismantel the motor. Perhaps you can rotate the stator over 180° and reassembel the motor back. Keep in mind that the rotor core must be in the middle of the stator core. PPS when a fan is turning in the other direction, the needed motor torque can be greater, this can overheat your motor and possible let it burn. Good luck.
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capri Power-User Join Date: Jul 2007 Location: Hyderabad, India Posts: 212 Good Answers: 3	#5 Re: Electrical Wiring Question 03/21/2008 12:18 PM
	If there is a capacitor in the circuit - just replace it. __________________ B +ve
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wangito Guru Join Date: Aug 2006 Location: Santiago Chile. Posts: 845 Good Answers: 7	#6 Re: Electrical Wiring Question 03/23/2008 8:11 PM
	CSM answer is correct do it. If no go, you will have to change motor. Changing the blade pitch won't do trick. try it on your own home ventilator, that is, if you have one... Wangito. __________________ Never trade luck for skill.
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Anonymous Poster (1); capri (1); case491 (1); CSM Engineer (1); rudy.leurs (1); wangito (1)

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