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Discussion Starter · #1 ·
I'm wiring a lathe drum switch, the guy took the motor out and tried to do service on it, chopped all wires going to drum sw and didn't label them, then mounted the motor with the nameplate inaccessible. I THINK I have an idea on how to wire, I just DO NOT want to smoke this.

Total i have 6 conductors going from Motor to the Drum sw.
3-Yellows
2-Blacks
1-white

Only wires with visible markings are 2 blacks in pecker head marked 5 & 6.

Any help would be much appreciated.








 

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Discussion Starter · #3 ·
Methinks , short of a motor genius, digging out that nameplate would be prudent Boston

~CS~
Ugh I know....The nameplate doesn't have a diagram, I was surprised because it's an old motor, GE I want to say.

I need to start somewhere. This is to a lathe, it's AT LEAST from the 60's, could be older so there's a good chance the motor has been replaced since. What do you think, remove all wires from the motor, and ohm test to find windings, etc?
Or should I tell him he, or I, needs to mount the motor so the nameplate is visible at the factory access panel? I'm working with very little info:
Motor compartment- 6 conductors 3-yellow, 2-black, 1-white. Then gets flexed to a junction box mounted on the unit ( appears factory as it doesn't have flex connectors, it utilizes compression from the boxplate) same conductors as in motor compartment, they are just all cut and un labeled, then from the junction to the 3 pole Drum switch. Again with no wires labeled.
 

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Discussion Starter · #4 ·
And if it helps, the guy seems to think it's single phase. I say "seems to think" because he's a machinist by trade and I don't know him well enough to judge his skill sets.

I'm also no motor genius, but I know they are on here. The motor has no visible signs of a capacitor? No square compartments or cap can like enclosures mounted.... Most single phase motors that I've seen do, but again this is a half decade old equipment IF the motor is original.

Single phase Induction start?? Did someone replace it with a 3-phase? I need to determine what type of Motor it is, so I think I answered my own question. I'm not going to take his word that it's single phase 240, and im going to tell him I need to view the nameplate however he wants to go about doing that is fine with me.
 

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Not giving much to go on. But I worked on a Allison Robbins years ago that had those same bars for changing direction and voltage.
The diagram was on the cover plate and made out of paper not much left after years of heat exposure .
Just my guess though!
 

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Discussion Starter · #7 ·
Hmacanada said:
Not giving much to go on. But I worked on a Allison Robbins years ago that had those same bars for changing direction and voltage. The diagram was on the cover plate and made out of paper not much left after years of heat exposure . Just my guess though!
It's the motor I'm concerned with, if I can find out the terminal numbers I would be in the clear.

Steve- my motor has 2 extra terminal posts than your picture.
 

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bostongtp said:
It's the motor I'm concerned with, if I can find out the terminal numbers I would be in the clear. Steve- my motor has 2 extra terminal posts than your picture.
You know with out seeing the motor plate it's just a guess.
If it's a lathe , I would almost lay money on the fact it's 3phase most machinery like that starts out that way.
Voltage could be anything depending where it came from.
Here 600v is common but have seen 240 volt three phase as well,
 

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Discussion Starter · #9 ·
You know with out seeing the motor plate it's just a guess.
If it's a lathe , I would almost lay money on the fact it's 3phase most machinery like that starts out that way.
Voltage could be anything depending where it came from.
Here 600v is common but have seen 240 volt three phase as well,
Thanks, and yes here I have 240v 3 phase
 

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Bilge Rat
motors and controls.........
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Need a bit more info; first, where were the leads cut? The motor or the drum switch?

I've never seen a drum switch set-up that had 6 wires from the motor to the switch, 3ø needs 3, 1ø needs 4.

I see 4 terminals in the motor with 2 jumpered together, this would suggest 1ø connected 230 volts. But where are the two start winding wires?

Are there 4 terminals plus two more leads coming from the motor?

Is the drum switch used for forward and reverse?

Yeah, I know; tons of questions and no answers....yet.

P.S. The motor is most likely GE, the paint color is right plus you can sort of see the GE logo. It could be split-phase (no capacitor) or the cap could be inside the endbell.
 

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Discussion Starter · #11 ·
Need a bit more info; first, where were the leads cut? The motor or the drum switch?

I've never seen a drum switch set-up that had 6 wires from the motor to the switch, 3ø needs 3, 1ø needs 4.

I see 4 terminals in the motor with 2 jumpered together, this would suggest 1ø connected 230 volts. But where are the two start winding wires?

Are there 4 terminals plus two more leads coming from the motor?

Is the drum switch used for forward and reverse?

Yeah, I know; tons of questions and no answers....yet.

P.S. The motor is most likely GE, the paint color is right plus you can sort of see the GE logo. It could be split-phase (no capacitor) or the cap could be inside the endbell.
Motor- Not sure if Leads were cut, there is 6 terminal posts on the motor board, plus 2 black wires comming from inside motor housing to pecker head, labeled with metal label markers 5 & 6. The 2 black wires comming directly from the motor (wires comming from inside motor, and not terminal posts on "pecker head" board with 6 terminals, not 4 and I believe there was 2 jumpers on 2 different posts.)

Drum switch- The switch has the forward and reverse option yes. Physically there is 6 wires going to it, all yellow. There is a, what appears to be, factory junction box on the unit where 3 of the yellows were cut, the other 3 yellows went straight to the motor terminal posts as seen in pic.

GE Motor- u was thinking the same think, like you said you can almost make it out. All the diagrams I find have no reference to a #6 lead....

When I measured in ohms, 2 of the yellows (unknown what numbers) I got 4 ohms to white, then from the other yellow to white I got a reading BUT I had to adjust the ohm meter to 200k ohms then it would show me digital reading. Does this mean I found the start and the run?
 

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Methinks , short of a motor genius, digging out that nameplate would be prudent Boston


~CS~
You need the nameplate data. The motor is probably a single phase dual voltage motor, under one H/P.
It looks like a GE, built in the 50's. It can't be a very large lathe and doesn't require a cap-start motor, as lathes are started no-load.
I'm trying to figure why they needed six leads out, unless it's a two speed motor. :rolleyes:
 

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Electric Al
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Is it possible to take a pic of the nameplate with a mirror and a flashlight , and yes (before someone makes a funny) a camera ?

With that info , you should be able to determine what the motor specs are !

I know from experience , that some machinery has motors that are specifically made for that piece of equipment .

That is all the help I can submit without more info ! :blink:
 

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Bilge Rat
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Ok, with new info, of course there are new questions........lol.

If I have read correctly, there are 6 terminal screws in the motor, plus two additional wires coming from inside the motor. Also, there are two sets of two terminals jumpered together.

If so, then it's almost certainly 1ø connected for 115 volts.

Perchance, do the two wires coming from inside the motor go to something like a light or maybe an oil pump? Or maybe even a start capacitor?

If so, that would explain two of the 6 wires from the drum switch, leaving 4 to operate the motor. This is normal for a 1ø setup.

If the above is true, then the two sets of two terminals jumpered together are the run windings, and the two lone terminals are start.

Since it's a white and 3 yellows, most likely the white is neutral, and if so it will be open when the drum switch is off, but connected to the incoming neutral when it is in either forward or reverse. If so, the white is connected to one of the jumpered terminals.

Now, find which one of the yellows is open when the drum switch is off, but connected to the incoming hot when it is either forward or reverse. This wire is connected to the other jumpered terminal.

The two remaining yellow wires can be tested as follows; one of them will be connected to the hot in forward, and the neutral in reverse. The other yellow will be the exact opposite; neutral in forward and hot in reverse.

If the above is true, these wires are connected to the lone terminals; this is the start winding. It is phased one way for forward, and swapped for reverse. This is accomplished by the drum switch.

If, after power is applied, forward is actually reverse, simply swap the two yellows on the lone terminals.

If you actually understood any of this, you're pretty sharp!!!!
 

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Discussion Starter · #16 · (Edited)
Ok, with new info, of course there are new questions........lol.

If I have read correctly, there are 6 terminal screws in the motor, plus two additional wires coming from inside the motor. Also, there are two sets of two terminals jumpered together.

If so, then it's almost certainly 1ø connected for 115 volts.

Perchance, do the two wires coming from inside the motor go to something like a light or maybe an oil pump? Or maybe even a start capacitor?

If so, that would explain two of the 6 wires from the drum switch, leaving 4 to operate the motor. This is normal for a 1ø setup.

If the above is true, then the two sets of two terminals jumpered together are the run windings, and the two lone terminals are start.

Since it's a white and 3 yellows, most likely the white is neutral, and if so it will be open when the drum switch is off, but connected to the incoming neutral when it is in either forward or reverse. If so, the white is connected to one of the jumpered terminals.

Now, find which one of the yellows is open when the drum switch is off, but connected to the incoming hot when it is either forward or reverse. This wire is connected to the other jumpered terminal.

The two remaining yellow wires can be tested as follows; one of them will be connected to the hot in forward, and the neutral in reverse. The other yellow will be the exact opposite; neutral in forward and hot in reverse.

If the above is true, these wires are connected to the lone terminals; this is the start winding. It is phased one way for forward, and swapped for reverse. This is accomplished by the drum switch.

If, after power is applied, forward is actually reverse, simply swap the two yellows on the lone terminals.

If you actually understood any of this, you're pretty sharp!!!!
Wow....for the info I gave you, I'm seriously impressed. I understood EVERYTHING you said loud and clear and am going to the site tomorrow. The 2 wires from the motor go through flex to what appears to factory junction box where they are cut, as well as a white and 2 yellows. I'm going to do exactly what you said, and I have a good feeling about it.

Whether or not it works I'll definetly keep you guys posted, again MTW thanks for taking the time to think that through and write that out, that's awesome!
 
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