vance lump
01-08-2024, 3:47 PM
I have a perplexing problem that just happened with my Delta shaper. Model 43-375. Single phase, 3 hp. Marathon motor. 220v. It comes up to full speed only in the clockwise, reverse direction. In counter clockwise, or forward, it spins slowly for maybe 20 seconds then trips the breaker in my panel.
A few days ago it was working great and had been for some time but I ran it a lot one day and it quit on me. I run it in CCW rotation. I pushed the on button and got a buzzing sound and very very little spindle movement. This was not in the middle of a cut, it buzzed at startup. It did not show any signs of bogging down just before either. Figuring it overheated and some thermal protection mechanism engaged, I came back two days later to roughly the same behavior, although now it will spin slowly in CCW for a short time until my breaker pops. With the junction box cover off I can see that there is a small electrical flash (arc?) coming from inside the magnetic contactor when the power is shut off in CCW, but this does not happen or the flash is much much smaller when its set to CW (as identified in this photo http://i822.photobucket.com/albums/zz142/zzarus/3phLVCStarter.jpg).
I have tested the reverse switch for continuity, it is fine. The magnetic starter switch seems fine as well. There is no manual thermal protection reset button on this motor or in the junction box on the side of the machine. From what I have read it is an auto reset, and it may not be resetting or I fried something else. The motor is a Marathon, I’m assuming original. It’s a mid-90s era Delta shaper. I cannot identify anything in the junction box that looks fried or burnt out. I opened the overload protection unit and it looks fine inside. My only clue is the small arc from the magnetic contactor when it is in CCW rotation.
I’m wondering if I fried the magnetic contactor and what could be done about that. I looked at motor starter units that others have recommended in other threads and they cost more than I paid for this machine ($400). I am mostly confused why it works in one direction not the other. I donÂ’t need both directions, so if there was a way to get it to only work in CCW I’m happy with that. The closest electric motor repair shop is 2.5 hours away so I’m trying to avoid that if I can. Any help is appreciated!
A few days ago it was working great and had been for some time but I ran it a lot one day and it quit on me. I run it in CCW rotation. I pushed the on button and got a buzzing sound and very very little spindle movement. This was not in the middle of a cut, it buzzed at startup. It did not show any signs of bogging down just before either. Figuring it overheated and some thermal protection mechanism engaged, I came back two days later to roughly the same behavior, although now it will spin slowly in CCW for a short time until my breaker pops. With the junction box cover off I can see that there is a small electrical flash (arc?) coming from inside the magnetic contactor when the power is shut off in CCW, but this does not happen or the flash is much much smaller when its set to CW (as identified in this photo http://i822.photobucket.com/albums/zz142/zzarus/3phLVCStarter.jpg).
I have tested the reverse switch for continuity, it is fine. The magnetic starter switch seems fine as well. There is no manual thermal protection reset button on this motor or in the junction box on the side of the machine. From what I have read it is an auto reset, and it may not be resetting or I fried something else. The motor is a Marathon, I’m assuming original. It’s a mid-90s era Delta shaper. I cannot identify anything in the junction box that looks fried or burnt out. I opened the overload protection unit and it looks fine inside. My only clue is the small arc from the magnetic contactor when it is in CCW rotation.
I’m wondering if I fried the magnetic contactor and what could be done about that. I looked at motor starter units that others have recommended in other threads and they cost more than I paid for this machine ($400). I am mostly confused why it works in one direction not the other. I donÂ’t need both directions, so if there was a way to get it to only work in CCW I’m happy with that. The closest electric motor repair shop is 2.5 hours away so I’m trying to avoid that if I can. Any help is appreciated!