Help Rewiring a Delta HD Shaper

[Joseph Spallina]

My Delta shaper had an issue where it would start and run in reverse, but would ‘freeze’ when trying to run forward. After several failed remedies, I am now attempting to forego the reversing switch, and directly rewire the machine for CCW rotation (at least until I can get the issue sorted out). The motor is a 3hp 230v single phase, with two run windings and a start winding (6 conductors on the motor: T1, T2, T3, T4, T5, T8). What I’m having trouble with, is how to wire in the starter capacitor, which is mounted on the exterior of the cabinet (not piggybacked on the motor itself), and run into a junction box, along with the power from the starter switch and the extended lines from the motor. The diagram below directs how the conductors should be attached to power. Could anyone let me know to which conductors the starter capacitor should connect? My understanding is that T1-T2, and T3-T4 are the run windings, and that T5-T8 is the start winding, but I haven’t run a resistance test on the pairs yet. Thanks in advance for any insight.
445506
https://sawmillcreek.org/blob:https://sawmillcreek.org/b03db3b3-41ab-4b2a-9456-73b0644700b4

[Dan Lambert]

Delta used several different motor manufacturers over the years, and exactly which motor is used on that machine is a required piece of information. I wouldn't hazard a guess without knowing the exact make and model of the motor so I could research the correct wiring configuration. There is a reason why the motor freezes when trying to run in forward, and I think you should determine what is causing that before you do anything else. It could be a bad reversing switch, or a number of other things, but finding the cause of that problem would be the first thing I'd try to figure out.

If the motor uses a true start capacitor, there is usually a centrifugal switch inside the motor to disconnect the start capacitor from the winding. A start capacitor is only supposed to be powered for a couple of seconds to get the motor spinning. In that case, the capacitor should typically be wired through the centrifugal switch.

If the motor uses a run capacitor (same electrical device, just different construction materials), then the wiring diagram inside the tap box should indicate where the capacitor should be wired in.

If you don't have a good wiring diagram, I'd take the motor (or at least the manufacturer's name and model number) to a motor repair shop and ask them for guidance in wiring it.

[Joseph Spallina]

Thanks so much for your reply Dan. The motor is a Dayton 6k632. The Wiring diagram had T1 going to L1, T4 and T5 going to L2, and T3, T4, and T8 tied together. Any info I can find on the motor shows a start capacitor piggybacked on the motor and internally wired. Since my machine had the start cap mounted externally, and wired to the motor through a junction, along with the starter switch, and the reversing switch, I'm looking for a way to recreate a that previously functioning configuration in order to further troubleshoot. I have previously replaced the reversing switch, only to get the same result (motor "froze" when attempting to turn CCW, but did not hum or buzz). I've also tried wiring it without the reversing switch, in what I believed to be its original configuration. When I did this, the motor started, and ran for a few seconds, then tripped the breaker. What I'm attempting to do now is eliminate the possibility of bad wiring before removing the motor for further testing (centrifugal switch if there is one, etc.). Given all that, which would be the appropriate set of conductors to connect the starter cap? (in this case, it's a pair of 455mfd caps wired together)

[Ron Selzer]

motor spec.s
https://www.grainger.com/ec/pdf/6K632_8.pdf
believe the capacitor is wired external due to the reversing switch,
not certain if capacitor value is right
good luck
Ron

[Joseph Spallina]

Thanks Ron. Yeah, the reasoning makes sense. And since the caps that are currently installed had worked for years, and still work in reverse, I'm comfortable moving forward with that value for now. Given the wiring diagram on the Grainger link you posted (which does match what is on the motor tag that I've been working off of), I'm still unsure across which conductors to patch in the starter capacitor, and I'm afraid to 'experiment'.

[Richard Coers]

Thanks Ron. Yeah, the reasoning makes sense. And since the caps that are currently installed had worked for years, and still work in reverse, I'm comfortable moving forward with that value for now. Given the wiring diagram on the Grainger link you posted (which does match what is on the motor tag that I've been working off of), I'm still unsure across which conductors to patch in the starter capacitor, and I'm afraid to 'experiment'.
You should not even consider experimenting. Randomly switching electrical wires is never a good thing and makes for expensive, but often impressive, consequences. Do you have a motor repair shop nearby?

[Joseph Spallina]

I do, and they're my next call. Just thought I'd check here to see if someone had a definitive answer before taking the motor out of the machine.

[Stan Coryell]

Joseph,
Your thoughts so far are correct.
I'm thinking someone connected the two capacitor wires together and attempted to wire the capacitor in series between T5 and T5. I don't know if that would work without ringing out the motor. I doubt it. I would figure out how the capacitor was wired from Dayton (look where the original capacitor cover is/ was) and reconnect it, even if you have to make those wires longer to remote mount the capacitor. Rewire the motor to whatever voltage you are using. It should run. Check back.

I suspect the centrifiacal switch prevents you from using T5 for the capacitor.

If you post a picture of the reversing switch it should not be a problem to wire it. (You only switch T5 and T8) In theory you only need a double pole double throw switch with two jumpers.

Stan

[Stan Coryell]

This is the basic idea of your motor.

Stan

[Joseph Spallina]

Thank you so much for your reply and for posting this literature, it's exactly what I've been searching for. Interestingly, my motor doesn't appear to have any remnant of a piggybacked capacitor (no covered over opening, or even any screw holes for external mounting), leading me to believe that this particular motor was set up for this external capacitor wiring. Patching the starter cap along the T5 line makes sense and, given where the centrifugal switch would presumably be located in the circuit, is the only place that makes sense and avoids backfeeding. Regarding the reversing switch, I have both the original and a replacement DPDT switch I purchased in case that was the culprit. If I can get this test circuit to work in both directions, I'll put the switch back in (and I understand how to do so). Does the attached diagram make sense as a next step to test?

445581

[Stan Coryell]

I've only ever seen small fan motors with remote capacitors. They always have separate wires for said caps. Your skematic above may work, I don't know. That said, the skematic I posted shows the cap between the centrifugal switch and the start winding, I believe this matters. Get some good pictures of the motor. I believe it started out with a capacitor and cover mounted to it.

[Dan Lambert]

That being a Dayton motor, I can guarantee that it;s not the OEM motor. That is a replacement that someone has installed in the past. Most of the OEM motors (if I remember correctly) were Marathon or GE. I would guess that the capacitor sizing is just whatever the PO could find that worked. It would probably be a good idea to determine what the motor spec calls for, and use that cap.

[Paul Haus]

That being a Dayton motor, I can guarantee that it;s not the OEM motor. That is a replacement that someone has installed in the past. Most of the OEM motors (if I remember correctly) were Marathon or GE. I would guess that the capacitor sizing is just whatever the PO could find that worked. It would probably be a good idea to determine what the motor spec calls for, and use that cap.
To take this one step further, did you check the motor specs to confirm that it's reversible? There should be something on the motor plate relating to reversing the motor.

[Ron Selzer]

To take this one step further, did you check the motor specs to confirm that it's reversible? There should be something on the motor plate relating to reversing the motor.

the motor nameplate state to change the #5 and # 8 wires to change rotation

[Joseph Spallina]

Just an update. I replaced the capacitors (just in case) and hardwired everything up according to the schematic above (no reversing switch), but got the same result: motor starts and runs perfectly in reverse (clockwise), but binds when attempting to turn counterclockwise (reversing T8+T5 on the diagram). Next step is to remove the motor from the machine so I can get to the end cap and centrifugal switch. I suppose a bad contact there could be a culprit. Motor shop is closed until Monday, so I'll take the weekend to see if there's anything obvious before bringing it in. Thanks everyone for their helpful replies in getting me to this point.

[Stan Coryell]

I'd be very surprised if the capacitors weren't mounted at 12 o'clock on top of the motor. Can you flip the shaper upside down? It will give you a better chance of getting to the motor.

Do you have the capacitors wired series or parallel? It's possible that the motor is capacitor start capacitor run.

I don't know if a motor shop would be much help, around here anyway. They would tell me to buy another motor.
It seems as though the windings are fine. Windings short open or short to ground. If your motor runs in one direction it should run in the other. Put the capacitors in series with T8 instead T5.

Could you post pictures of the motor nameplate and the 12 o'clock view of the motor. Again, I would be really surprised if the capacitors didn't start out piggybacked at 12 o'clock. (I don't think the motor will fit in the cabinet with the capacitors in the way)

[Joseph Spallina]

You're probably right about the capacitors, although I can't feel anything resembling a cover plate or a bolt hole on the surface of the motor. The shaper is tied/bolted to my cabinet saw by its fence rails, so it's a pretty big ordeal flip the cabinet or get photos. I can pull the motor out the side of the cabinet though and will take pictures, just haven't had the chance yet. The capacitors are wired in parallel with a resistor across the terminals at the end of the chain.