Requesting help wiring original GE instant reverse motor

[Oldmansteve]

Looking for some help with correctly wiring an original instant reversing GE motor. The GE motor # is 5KC63AB776. The relay is # 5099122 BE1.

I have read, re-read, and re-read again every post on this site and the internet in general on the wiring for this motor and relay. But,many of the links in those posts are broken and while they appear they would hold the answer, they are dead links. Yes, I know the relay is an obsolete unobtainable part. Yes I know I could replace the motor and even convert to 3-phase w VFD etc. I do not want to do that. I want to get this going again with what should be an easy fix if someone who has the same components would chime in with a description or pic.

The motor worked normally in forward and reverse when purchased, although I didn't specifically test for instant reverse. Motor was disassembled and reassembled (needed cleaning of caked on oil/dirt etc to cool properly). No wiring was changed. The motor will now not run without hand spin starting. Start capacitor checks out to be okay. Reversing switch wired correctly and clean. I believe the problem is isolated to the relay wiring. Upon inspection of the relay I see the contacts are covered with carbon. I was able to clean one set of contacts, but the deeper set (N/O set) I am unable to get adequate access to, and the contacts are not removable from the plastic housing. But, remember, the motor started and ran fine before removing, despite the carbon buildup in the relay. When initially removing the relay I took pics and found 4 wires from motor to relay box. Green, Yellow, Red, Black.

Red is hard wired to the coil.

Green screwed to the N/C contacts.

Yellow screwed to the N/O contacts.

Black ???

However, the Black wire was found floating in the box and not connected to anything. Black wire has the factory ring terminal on it just like the Gr and Y wires but I have no idea where it goes. So, am hoping someone with the same original motor/relay would be willing to remove their relay cover and snap a pic for me. After playing around with the multimeter a bit, I was able to bypass the relay and get the motor to start and run and reverse by removing the relay completely and using black as common and yellow/red together as the other 120V pole, leaving green completely isolated. But, not sure if that is correct. So, 2 questions:

1. I would really like to put the relay back as designed because I do believe it works, but for the life of me I can't figure out where that free black wire with the ring terminal belongs on the relay. Need a pic.
2. If in-fact, the relay won't work correctly due to carbon, or later becomes nonfunctional and I need to bypass it, How do I wire the motor? As stated, I found what 'seems' to work, but do not have the knowledge to know if this is correct or if I am going to burn up some windings in short order by doing such. Need some help here.

First pic below shows exact relay wiring when initially disassembled from running motor. Second pic shows my relay bypass which 'seems' to make it run properly (yellow attached to the winding lead which was previously factory wire nutted to red lead which went to coil).

Thanks in advance.

 

[Paula]

Hi Steve,

Sorry to hear you are having trouble getting your motor to work correctly. From your pictures, it looks very similar to the one I rebuilt. Let me do some checking, and see what I can find out. By the way, did you install the colored plastic sleeves on some of the wires? I only ask because my motor didn't have anything like this, and it may be a sign that someone else has been inside there already. Not necessarily a bad sign, but one wonders.

Regards,
Paula

 

[Oldmansteve]

Hi Steve,

Sorry to hear you are having trouble getting your motor to work correctly. From your pictures, it looks very similar to the one I rebuilt. Let me do some checking, and see what I can find out. By the way, did you install the colored plastic sleeves on some of the wires? I only ask because my motor didn't have anything like this, and it may be a sign that someone else has been inside there already. Not necessarily a bad sign, but one wonders.

Regards,
Paula

Paula, Thank you so much for responding so quickly, I really appreciate any help you can offer. No, I did not apply any plastic sleeves to the wires. It is just as it came apart for me, and I am near certain it has never been apart since original factory assembly.

 

[Paula]

Steve, I don't know if you've seen it, but there is a thread here where I discuss the process I went through with my instant-reverse motor. Some of the links to the pictures have expired, but I can supply originals if needed. Here is the link to the part of the discussion pertaining to the motor:

https://www.practicalmachinist.com/forum/threads/1947-model-9a.128005/page-5

There is a rather drawn out discussion concerning the theory of operation of the instant-reverse feature, which you can ignore for your purposes, unless you're just interested. The schematic is the main document... it shows how the system is electrically connected, though not necessarily how it is physically wired. It looks like there is a terminal screw missing at the lower-left in the picture of your relay. This is terminal #7 in my schematic, and should connect to one side of the run winding. I'm attaching some of the pictures here, but I recommend reading through the discussion linked above as well. Though your motor and relay numbers are slightly different from mine, they should function and be wired the same way.

Once you've reviewed this, feel free to ask any questions you might have.

Paula

 

[Oldmansteve]

Paula, Thank you so much for the info, link, and mostly the pics. I believed that I was missing a screw on the relay and the pic confirms that. I replaced the screw, reassembled, and all works as intended, instant reversing and all! The contacts could still use a bit of cleaning, but I don't think the relay comes apart (looks like the metal tabs were press fit into the plastic housing). If you know how to disassemble the relay that would be really useful information. If not, I will use as is, or on second thought, maybe bypass (I am concerned about arcing and sticking contacts in an area not readily observable.). Any idea how to safely bypass the relay ?

 

[Paula]

I don't remember if I disassembled my relay. I don't have any pictures of it apart, so I probably didn't. It looks to me like the two center screws might allow disassembly? I would try removing all six screws and see if it comes apart. Other than that, I don't know. I suppose that the motor could be rewired to bypass the reversing relay, but I'm not sure how without researching it a bit.

Let us know if you're able to get the relay apart. Good luck!

Paula

 

[Oldmansteve]

Paula, Yes, I was able to disassemble the relay, clean and reassemble. Now wired correctly it works well. But I may disconnect it anyway as I am not sure I want the ability to instant reverse on a lathe with a threaded spindle.

 

[1oldschoolpirate]

This is gold. I've been looking forever for a wiring diagram for my South Bend C9-10JR that I inherited from my grandfather's brother. I think this may be what I need! Thank you.