Motor Problem on a Mark V Greenie

jamhard · Post by **jamhard** » Sat Feb 26, 2011 1:04 pm

GE motor model 5KC39NG202.
3/4 HP
When I took the motor out, there was a lead broken on the on/off toggle switch. (I fixed the wiring on the toggle switch and its working correctly) When I took the motor down, some of the wiring came loose, and Im not sure about the way the wiring goes back onto the motor.
The motor has a start relay, and a capacitor and I'm not sure about the wiring diagram because there is none in the book or on the motor. I checked the motor when disassembled and it doesn't have a centrifugal start cutout switch. I took the start relay apart and found out that the coil must have magnitized the steel cutout arm that cuts out the start winding when energized because it will not release from the magnet when power is cut from the coil. I tried stronger springs to make it release with the same results. Thats why it must have blew the start capacitor and keeps overheating the motor.
I tried calling around to find a new relay in the Norfolk Va. area with no luck! The relay information is as follows:
MFG. General Electric
Mod. 3ARR1 AE7J3
MAX. START WDG AMPS50
VOLTS 120
CYC. 60
THIS NO. ON COVER 7 26 55
Can you Help? Thanks.

JPG · Post by **JPG** » Sat Feb 26, 2011 1:24 pm

jamhard wrote:GE motor model 5KC39NG202.
3/4 HP
When I took the motor out, there was a lead broken on the on/off toggle switch. (I fixed the wiring on the toggle switch and its working correctly) When I took the motor down, some of the wiring came loose, and Im not sure about the way the wiring goes back onto the motor.
The motor has a start relay, and a capacitor and Im not sure about the wiring diagram because there is none in the book or on the motor. Can someone please point me to where I can get a wiring schematic or assist me with the wiring/troubleshooting.
I rewired it, because the way it was originally wired was that one side of the capacitor went to the run winding. I changed it to the start winding, and the motor ran, but it started overheating. When I put a load on it, the motor started cutting out.
FYI the capacitor blew out when it was attached to the run winding.
Could this be a problem in the centrifugal switch in the motor, because I have not taken the motor apart yet?

Thanks.

Not a good idea!

Hopefully moving it 'back' and replacing the capacitor will allow it to run again. The cutting out was probably due to an internal thermal protective device(hopefully so!).

Not too sure what the sequence of events was here.

Yes the start switch could be 'stuck' closed, but a more common failure is it becomes contaminated with sawdust and sticks open.

Hopefully Bill Mayo can help you with proper wiring.

P.S. The start relay(may indicate the absence of a start switch) is a likely culprit here.

billmayo · Post by **billmayo** » Sat Feb 26, 2011 10:02 pm

This GE Motor uses a start relay instead of a centrifugal switch.

[ATTACH]12043[/ATTACH]

The wire between the relay 5 and the capacitor is black, not red. I noticed the schematic of wiring is not correct, so disregard the attached images. I will redraw it tomorrow. Sorry. Contact me if any questions. Thanks.

billmayo · Post by **billmayo** » Sun Feb 27, 2011 6:50 pm

billmayo wrote:This GE Motor uses a start relay instead of a centrifugal switch.

The wire between the relay 5 and the capacitor is black, not red. I noticed the schematic of wiring is not correct, so disregard the attached images. I will redraw it tomorrow. Sorry. Contact me if any questions. Thanks.

This is a corrected schematic for the 3/4 HP GE motor. All I need is someone to graph/draw this schmetic with colored and straight lines. Thanks.

[ATTACH]12050[/ATTACH]

JPG · Post by **JPG** » Sun Feb 27, 2011 8:48 pm

billmayo wrote:This is a corrected schematic for the 3/4 HP GE motor. All I need is someone to graph/draw this schmetic with colored and straight lines. Thanks.

[ATTACH]12050[/ATTACH]

I think Jamhard also needs to know where those wires are connected internally also(he been moving em!).

wannabewoodworker · Post by **wannabewoodworker** » Sun Feb 27, 2011 10:06 pm

Bill I did up a quick and dirty color schematic of what you posted hopefully this is what you were looking for colors added for clarity.

wannabewoodworker · Post by **wannabewoodworker** » Sun Feb 27, 2011 10:15 pm

Bill,
Here is my very quick and dirty edit of your schematic adding colors as you asked for.

dusty · Post by **dusty** » Mon Feb 28, 2011 3:42 am

wannabewoodworker wrote:Bill,
Here is my very quick and dirty edit of your schematic adding colors as you asked for.

Is this motor reversible? It appears as though it could be by simply exchanging the red/black wires at the motor.

Fla_Jim · Post by **Fla_Jim** » Mon Feb 28, 2011 8:56 am

I believe the 'red' wire is for the start windings.
When the motorstarts, the capacitor gets charged, the voltage causes the potential (start) relay to open, causing the start windings to be out of the circuit. this usually happens in less than a second. The start windings are just as named, to get the motor spinning.
Some motors use a centrifugal switch to accomplish the same thing.

jamhard · Post by **jamhard** » Mon Feb 28, 2011 9:03 pm

Thanks for the help to all the folks that responded to my motor problem. B/regards Jim Harding