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QUESTION: I have a leeson 1/2 hp reversible 120/240v motor.  I use it to raise and lower my antenna tower.  What I need is the wiring to go up and go down and a middle position for off. Also the wiring from the motor to the switch.  I am an electronic tech familiar with electricity, but not with motors.

I have a waterproof dpdt switch with the middle position off, a waterproof connection box and the motor is totally enclosed.

I have opened the connection box and have all the marked wires,e.g., P1, P2, T4&T5 tied together 2T1's spliced together, and T2, T3 & T8 tied together.  

I presume P1 & P2 are the main power wires and I believe T6 & T8 should be reversed but everything else confusers me.  

I would appreciate your help with a drawing if possible.

Thank you, Joe.

I would appreciate the necessary wiring.

ANSWER: I apologize for the delay, but I have gotten a new email address, and trying to get everything transferred to this new one. First, you will need a three pole double throw switch. Your motor is connected for 220 volts. Is that the voltage you want to use? I will try tonight to get a drawing up for you.

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QUESTION: I bought the motor as a 120v motor.  If it is wired for 240v I would appreciate how to convert it to 120v.  I need the correction and the wiring to reverse the motor via a switch.

Thank you.

ANSWER: First separate all the leads. Install all the insulated jumpers.  Then connect all the "T" leads to the switch as shown. (I do not know why you would have two leads marked T1, have never seen this before, but leave them connected as one lead.) Now connect power line 1 to P1. Connect P2 to where L1 is shown on switch. L2 remains as shown.

"I presume P1 & P2 are the main power wires and I believe T6 & T8 should be reversed but everything else confusers me."  P1 and P2 are the leads to the overload. I think the T6 may be a typo error, as T5 and T8 are swapped to reverse the rotation.

Hope this helps, and let me know how it turns out.  

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QUESTION: I really appreciate your help.  This note is just to bring you up to date on what I have done.  You were right the motor was connected for 240v.  I have the Leeson spec sheet and figured out how to connect it for 120v.

For 120v on the line 1 I have p1.  On line 2 for cw rotation I have connected t2/t4/t8.

For ccw rotation on line 1 would have p1 and on line 2 i would have t2/t4/t5.

There is no separate t1.  There are 2 t1's and they are tied together with a lock nut. This then is different from your drawing for the switch for which you show a single t1. I am looking at the motor now and it is as I wrote.  And the connections are from the Leeson spec sheet which shows no t1.

If I am wrong let me know, but what do I do about t1 on your drawing?

What other leads are connected to T3? What is P2 connected to? Not sure what Leeson has done here, but it is not standard. For reference, here is the NEMA standards,

Joe, I found a Leeson diagram at the shop today, and now I see what they did.

Separate the T1 leads, and with the other leads also separate, find the T1 that has continuity to P1 and P2. Now connect this T1 to where I show the L1 on the switch. Connect L1 to P1, and connect the other T1 to the T1 connection on switch. Insulate P2.

This should work for you.  

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Charles C. Jones


Let Me help you with your problems with single phase and three phase electric motors. I can tell you how to troubleshoot your motor problems. From simple testing of capacitors, how to test your windings, replacing bearings, and general maintenance. Before we go any further, remember these words of advice: Disconnect the power before you do anything! Please limit your questions to electric motors and there immediate components. I review each question, and if I can answer or help, then I will. If you receive a rejection, it means it is out of my expertise, and just do not have the answer. I'll be waiting for your question.


I have 40 years experience in the repair of electric motors and related equipment. I am a master machinist in the field of motor repair. I was employed with my company for 35 years, but retired in May of 2013. The downside to that is I lost access to a lot of technical data. I will still try to give you the most accurate advice that I can.

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