Delta HD Shaper 43-375 motor issue

[vance lump]

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!

[Rod Sheridan]

Hi, it’s an issue with the reversing switch.

The reversing switch flips the start winding leads so that the motor changes direction when starting.

That’s why the motor trips the breaker in one direction, the start winding isn’t connected so the motor has no CEMF and very high current.

Regards, Rod

[vance lump]

Since the continuity tested fine on the reversing switch itself, could that mean there is something wrong within the motor housing where the reverse switch wires connect to the winding leads? That would probably mean taking the motor out. I have taken the reverse switch apart and inspected, everything looked fine.

Can I test the motor circuit somehow without taking it apart? I have 4 wires coming from the motor to the reversing switch. 2 are power in. I suppose the other two are the circuit for forward or reverse?

[Bill Dufour]

Single or three phase, voltage?
Three phase has no start windings or capacitors to go bad.
Bill D

[Rod Sheridan]

Hi Vance, if the motor works in one direction, it works in the other, you use the same two windings in both directions.

If it consistently doesn’t run in one direction, but always runs in the other, it’s the reversing switch.

If you want to prove that flip the start winding wires at the switch.

Regards, Rod

[vance lump]

Single phase, 220v. I edited the original post to include more info. There is definitely a start capacitor, and it appears in good condition from looking at it, no lumps or weirdness.

[vance lump]

I did swap a couple wires at the switch yesterday. There is another quirk that was pre-existing before this issue came up: the rotation of the motor was opposite what the switch said. So if the switch was put into reverse, it would spin CCW, forward was CW. So I switched two wires that I believe connect to the motor, and now the switch shows the correct spin direction, but still only spins in CW rotation. CCW doesn't work. Before changing these wires, the switch would be set to FWD to spin CW, now it is set to REV for CW rotation. I'm not sure if those are the two winding wires you mean, Rod. I am under the impression that the other two wires at the switch are for the power source.

[Bill Howatt]

Nothing to add about the works in one direction problem but are you viewing the motor in the designated direction. It can have a "OPE" designation which refers to the direction of the spin as viewed from: Opposite Pulley End. This is the opposite rotation compared to what you would see when viewing from the pulley end.

[vance lump]

The motor says CCW-OPE FWD POS. The direction that I am viewing/referencing is what the spindle is doing. Is that incorrect?

513500

[vance lump]

The reversing switch has 4 wires going to it. T4 and T1 are hooked up to the black and white power lines. T5 goes to what I think is the starting capacitor, it says “for motor starting” on it. T8 goes into the motor housing, I’m guessing to the start winding? I have already swapped T5 and T8 which resulted in changing the reversing switch behavior so that when the switch is pointing to reverse, the spindle turns CW. Previously it pointed to forward and turned CW.

Rod, I don’t know which start winding wires you advised me to flip.

Edit: I have swapped the two power wires and got the same behavior but with the switch in the opposite position. Swapping the wire to the starting capacitor and T8 that goes into the motor is the same result.

[Rod Sheridan]

So the motor always runs with the switch in one position, although the direction of rotation changes when you swap the wires?

If only one position of the switch makes the motor run, it’s a defective switch.

Regards, Rod

[Bill Dufour]

The linked photo to a motor controller is a three phase contactor with overloads. There is no reversing function.
How Many wires come out of the motor? Is it single voltage or dual voltage? Single speed or dual speed?
BilL D

[vance lump]

Rod, there is a misunderstanding. The motor behavior is the same no matter what I do. Only spins at full speed in CW rotation. If I swap wires at the switch, the switch could be in the left or right position and the motor behavior is the same. Before wire swap: switch in left position motor spins CW, switch in right position will not spin CCW. After wire swap: switch left, motor won’t spin CCW, switch in right position, motor spins full speed CW. So both sides of the switch can power the motor at full speed. This is why I question the switch being the culprit.

Bill, I know the first image I linked is for a 3 phase machine. Mine is single phase, dual voltage set to 220v plugged into a 30amp 220 line. I used that first image to identify components in the LCV box on the side of the machine. The setup is mostly the same for single and 3 phase, minus a few wires. The motor has one speed, and there are two pulleys to decide rotational speed of the spindle. This behavior continues whether the belt is on or off, and cutters are on or off.

I have drawn a diagram of the wiring for the motor, since pictures are hard to take that show anything worthwhile. In the diagram, SC is what I assume to be the start capacitor, and RC is run capacitor. All wires are black, minus a pink one that is noted. Probably not that important but I figured I would mention it.

513558

[Bill Dufour]

Two speed shaper but only a one speed motor, correct?
Bill D