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Electric Motors/Wiring 1hp motor to reversing drum switch



Motor diagram
Motor diagram  
I currently cannot get my motor to turn in both directions using a drum switch. It needs to be able to turn clockwise and counter clockwise. I am Wiring it 110. Wire from switch to motor is black, white, red, and orange. It is a smith and jones motor from harbor freight being used on a boat lift. Any help would be nice cause I can't find any help online

Kendall,  I need clarification,    you state you CURRENTLY cannot your motor to reverse,   does that mean it did in the past?  Or is this a new install?

I need to know if we are repairing a former operating switch, or wiring a new motor and controller.

I can also tell you these drum controllers are often very difficult to wire as single phase motors are wired a variety of ways,   some with four leads, some with six, seven,  so on,     

Four leads being wired for 110  is another concern,   if you have dual voltage ratings  it takes all four leads to change voltages,      you need a series connection for the high voltage connection and a parallel connection for the low voltage connection.

If you used the connection diagram provided I see no cross reference for numbers to colors,    when in the 110 mode, [normally 5 and 8?

The next concern is this antique drum switch. With the corrosion and age, it could have contributed the failure of the prior motor.

At the least you need to clean up those connections and make sure the corrosion has not wicked up the actual wire.

 The existing connection of four leads must swap orange and red with black and white,  in other words   one direction has black and orange to line,   white and red to line,      to reverse the switch puts black with red to line and white with orange.

Because they connect one of the P leads to a center tap to keep the start winding at 110 volts,  I see no way to drill down the connections to parallel and swap 5 and 8 with that switch.

If you look closely at the new motor connections   the only difference to reverse in the is the reversing of motor leads 5 and 8.  

So how you are going to break the center tap connections from P2 which is simply a bundle wired and taped off, I see no way   if you put P1 on either black or white,  now you have to swap 5 with 8,  which means you have to get 5 off the three wire bundle and then get 8 into the three wire bundle,     Even at 220 we have the same problem.

If you get a new drum switch  there are drum switches with enough connection points to do all this swapping,   but that is not an inexpensive option,   but looking at that old crusted switch it appears to need a complete cleaning and some kind of inspection of the contacts,  my bet is they are worn and likely filled with carbon or carbon tracking,  

That is a long link to diagrams for drum controllers,    as there is no way I can tell if there are extra contacts on your existing  or what they go to  [looks to me like there is only 4 connection points anyway,   and when you lay the connection diagram out, it is going to take more than 4 to reverse 5 with 8.    But that is the goal if it helps    if you tried to connect a bundle of wires from the new motor to one contact there is no way to pluck one wire out of each twice and swap them with that controller,   the old motor was probably a PSC type motor  or simple split phase,   because it just about had to be  two run leads and two start leads,       

So what to do? Take your motor to an electrical supply house so they can see the diagram and pick out a drum controller that will work,      

If you can return the motor,  I would suggest you got with a drive and three phase converter,   and a three phase motor,     it makes life so much easier,   gets rid of the complex single phase, and comes in one enclosure      it has conversion to three phase,  has reversing and ramp up time adjustments along with braking  all in one box     

That or a new controller,     sorry for the bad news but this is not uncommon,     with the P leads  on the new motor there is just no way to drill the connections down to four leads,   

If you go the three phase route   often the controller and THREE Phase motor both are about the same price as single phase motor by itself,     much less costly for three phase  no switches protectors or any other devices to fool with,        

The drum controller for the single phase will be fairly expensive    so it might be worth doing some shopping      and price comparing  

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Three phase/ AC DC single phase motors, controls, any problems or failures, motor installation, performance issues, connections. All other electric motors/gearboxes/apparatus. Specialty repair concerns, obsolete motors and solutions. Other mechanical or specialty equipment. See my profile under Home/electrical at this site


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