Need Advice Need recommendation for motor repair

[creasman]

The motor on my dust collector stopped working last week. I'm hoping it just the starter/capacitor. It was running fine when I cut it off. A few seconds later it wouldn't come on again. It's a 5hp Leeson 230v single-phase motor. Does anyone have a recommendation in the Raleigh area that works on motors? I found 2-3 doing a Google search, but prefer to have a recommendation from a past customer.

Thanks,
Jim

 

[pop-pop]

I should be able to diagnose that for you.

 

[creasman]

Thanks, Mike! I'll send you a PM to work out the details.

 

[Ted P]

I have a meter to check capacitors but will be out of town till the end of the week

 

[Michael Mathews]

If the motor has a capacitor on the outside of the frame, then most likely is also has a centrifugal switch to disconnect the Cap. after the motor is spinning. One way to know if the Cap or centrifugal switch is bad is when you turn power on to the motor, does it hum? Second, get the motor shaft spinning then apply power. If it takes off and runs up to speed, then it's one of the two. I've had corroded contacts on the centrifugal switches before causing this situation.

 

[creasman]

If the motor has a capacitor on the outside of the frame, then most likely is also has a centrifugal switch to disconnect the Cap. after the motor is spinning. One way to know if the Cap or centrifugal switch is bad is when you turn power on to the motor, does it hum? Second, get the motor shaft spinning then apply power. If it takes off and runs up to speed, then it's one of the two. I've had corroded contacts on the centrifugal switches before causing this situation.

There are two capacitors one the outside of the frame (assuming both "bump" has a capacitor). I'm pretty sure the motor was still spinning when I turned it back on. It had only been a few seconds as I adjusted fence. It typically spins a while after cutting the power due. It does not make any noise when I turn it on.

I currently have the motor out of the frame. However, the impeller is still attached. Spinning it and then supplying power could be a tad dangerous. I may give this a try after making sure everything is stable.

Thanks

 

[creasman]

Shout out to Mike (@pop-pop)! He diagnosed the problem as a bad reset switch. I'm in search of a replacement now. AFIK, it had never tripped before and picked this moment to stop working.

 

[pop-pop]

A primary clue was no hum. For the most part, no hum means an open main.

The thermal circuit breaker (official name) trips when the motor draws too much current and is installed in series with one of the mains. Often reset with a red button but this one was black.

Conversely, a stalled motor with a hum means the mains are intact. That is the point when you start looking at centrifugal switches and capacitors (assuming the motor spins freely).