# Need Help Replacing Motor On Enco 110-2075 Engine Lathe



## CannonFodder (Dec 15, 2016)

Sorry, my friends, somehow I was born with zero abilities in electrical matters.

My original motor of 25 years has burned out (Kunming 1.5HP).  I found a new Baldor L1319M on eBay and got a good price.

There, that's the end of my electrical knowledge.

The old motor's junction box looked like this.




The four wires in the corners with the white sleeves are the ones coming from the lathe to the motor.

The new Baldor has 9 wires in the junction box.  Two are unlabeled and have been joined together.  The rest are labeled 1,2,3,4,5,J, and 8.

The picture on the junction box looks like this:




I need to run 230V, single-phase, reversing.

Here is a picture of the Wiring Diagram for the lathe.





Is that enough info?  How do I twist together the new wires in the Baldor motor to connect to the wires Z2, V2, Z1, and U1 which go into the lathe?

I can run down more information if you need it.

I sure appreciate the help, I am dead in the water!

Thanks,

CannonFodder (Robert)


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## CannonFodder (Dec 17, 2016)

I have edited my original post with some (hopefully) clearer labeling.  Can anyone help me with this wiring?

Thanks,

CannonFodder (Robert)


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## mksj (Dec 17, 2016)

You might take some pictures of the contactors and controls to give us an idea of what is activated in the forward and reverse direction. I always have difficulty following these type of wiring diagrams. In another single phase Baldor motor replacement on a lathe, it was a bit of a challenge and required a different contactor wiring and a motor cable with 5 wires if I recall correctly. The other issue I see is per the diagram, the current contactors show a 29VAC connection, which I have not seen before, although there is a 24VAC tap on the transformer. At least from what I can see, it would require some significant rewiring to get the Baldor to work, but I may be missing something.  I need to map it out in some diagrams, hopefully someone else has a better solution.


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## master53yoda (Dec 17, 2016)

after connecting test with a jog and if that is ok bring it up to speed.    do this in both directions

240 vac high voltage configation
jumper 2 and 3   
U1 to 1
V2 to 4
Z1 to 5
Z2 to 8
J is not connected to anything but needs a wire nut for insulation


The control wiring is reversing the power to the run windings and leaving the power straight to the start windings,  Asian controls tend to use this configuration and it is not what is commonly done in US control systems.     The baldor diagram typically anticipates the use of  a reversing  relay to reverse the start windings.
Good luck

Art b


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## markba633csi (Dec 17, 2016)

Trying to follow along here: So in the original config U and V were the run legs and Z1 and Z2 were the start legs.  U and V were being reversed by the two relays/contactors Km2 and Km3.  Correct? 
What is that FR symbol with dotted line in series with the U and V legs? 
Mark S.


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## jim18655 (Dec 17, 2016)

This is the same model and vintage as the lathe in this thread:http://www.hobby-machinist.com/threads/is-this-wired-for-110-or-220.53162/


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## mksj (Dec 18, 2016)

master53yoda said:


> 240 vac high voltage configuration
> jumper 2 and 3
> U1 to 1
> V2 to 4
> ...


I do not follow how this addresses the Baldor motor wiring where 2, 3 is joined to 5 for forward and joined to 8 for reverse. Five and 8 are alternately connected to one side of the line when not connected to 2 and 3.  Mapping it on the schematic 5 and 8 are both connected to one side of the line at the same time in both the forward and reverse contactor. I believe FR is the contactor that closes when the start button is pressed, goes open with the E-Stop.


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## jim18655 (Dec 18, 2016)

Good catch, mksj. The start winding needs to be connected to the junction of the two run coils so that it only gets 120v applied. As master53yoda has it I think it will get 240v applied. This will need to be connected like the motor in the post I referenced in an earlier reply. One of the motor leads won't be used and the running power will get swapped in relation to the start coil.
It's too late for me tonight to research the connections but I'll look at it tomorrow morning.


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## jim18655 (Dec 18, 2016)

My suggestion for discussion:
3-2-5  connected
8   to   Z1
1 to V
4 to V (reverse lines if FWD/REV are wrong)
insulate Z2 

Contactors will switch phase of the line wires.
Start coil will stay the same phase and 120v to the junction of the two run coils


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## TomS (Dec 18, 2016)

jim18655 said:


> This is the same model and vintage as the lathe in this thread:http://www.hobby-machinist.com/threads/is-this-wired-for-110-or-220.53162/



Kinda the same but with a few differences.  My lathe (model 110-2072) is also a 1989 vintage.  The most significant differences are my motor has 6 wires plus a ground and has two contactors is the controls circuit.  I have yet to find a electrical schematic for my machine anywhere but with the help of the members of this forum I'm zeroing in on the source of my problem.  

Tom S.


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## CannonFodder (Dec 18, 2016)

Many, many thanks for your efforts looking into this problem.  You're awesome.

Here is more information on the distribution panel, and a different view of the "Electrical Equipment Connection" from the manual.

First the Electrical Equipment Connection page:






My lathe is up against the wall, so the best I can do at this time are these 3 pictures of the distribution panel from top to bottom:










A million thanks,

CannonFodder (Robert)


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## CluelessNewB (Dec 18, 2016)

Edit: Deleted wrong voltage diagram oops that was a waste of time!

It looks like for 220V You will need to have 5 wires (not counting ground) coming from the motor.  The original motor only had 4.   I think, but I'm not 100% sure that you can rewire relays KM2 and KM3 to work with the new motor.


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## markba633csi (Dec 18, 2016)

jim18655 said:


> My suggestion for discussion:
> 3-2-5  connected
> 8   to   Z1
> 1 to V
> ...


Should be 4 to U not 4 to V  
Mark S.


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## CluelessNewB (Dec 18, 2016)

Note that when wired for 220V to reverse you must swap wires 5 & 8 to reverse direction so wiring 3+2+5 permanently will not work.

I do not believe you can wire this motor for reversing with only 4 wires leaving the motor.  I do believe you can rewire the two contactors KM3 (and the other which i believe is KM2 but just marked M2 on the diagram) so they would work with the 5 wires required.


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## jim18655 (Dec 18, 2016)

markba633csi said:


> Should be 4 to U not 4 to V
> Mark S.


Typo on my part.


CluelessNewB said:


> Note that when wired for 220V to reverse you must swap wires 5 & 8 to reverse direction so wiring 3+2+5 permanently will not work.
> 
> I do not believe you can wire this motor for reversing with only 4 wires leaving the motor.  I do believe you can rewire the two contactors KM3 (and the other which i believe is KM2 but just marked M2 on the diagram) so they would work with the 5 wires required.


Reversing either the power or the start will switch the phase relationship between the start and run winding and reverse the motor. You actually can do this with three wires from the control to the motor


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## CluelessNewB (Dec 18, 2016)

jim18655 said:


> Reversing either the power or the start will switch the phase relationship between the start and run winding and reverse the motor. You actually can do this with three wires from the control to the motor



Yes reversing the phase relationship between the run and start windings will change direction.   I believe for this motor 5 wires are required if you want to keep the thermal overload active.    

If you look at the Baldor connections (mkjs diagram above) you will see that the starting winding is never connected directly across 220 but rather in parallel with only 1/2 of the run winding (getting only about 1/2 the voltage)   It may be possible to hook it up with 4 wires but I believe you will not have thermal overload protection for the starting winding in one direction then.


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## jim18655 (Dec 18, 2016)

The thermal is in the run winding so it will work regardless of the power connection to the run winding.
Permanent connection of the start winding  2-3-5 or 2-3-8  will reverse the phase relationship if you reverse only the phase connections to the run winding.

line A -1-wwww-2 -----5-----3-wwww-4 - line B  (www= coils)
.xxxxxxxxxxxxxxxxxxxx| 
.xxxxxxxxxxxxxxxxxxxw(connect to 5)
.xxxxxxxxxxxxxxxxxxxw
.xxxxxxxxxxxxxxxxxxx8
If 8 is connected to line A then power will flow to line B through the 3-4 coil as there won't be a voltage difference to the A phase.
if the run phases are reversed then power to 8 will flow to line B through the 1-2 coil effectively causing a phase reversal.
Hard to show - the forum changes the formatting.


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## CluelessNewB (Dec 18, 2016)

But if 8 is connected to B the start winding will bypass the the thermal overload.  If the centrifugal switch sticks, one of the more common failure modes...


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## mksj (Dec 18, 2016)

The thermal switch is for the run mode. If 2,3 and 5 (or 8) are connected, then the start coil is connected to the center of the run coils. One side of the power 4, is always connected through the thermal oveload regardless if 5 or 8 are connected to 2 and 3. Since the motor is running on 240VAC split phase, it should not matter which leg is connected to the thermal overload switch as opposed to 120. As I am understanding the connections, the motor direction is a function of flipping the incoming AC phase connections, alternatively switching the motor start winding phase.  Not too familiar with the Baldor's single phase wiring, and on a previous install posting used 5 motor wires and rewired the contactors.


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## jim18655 (Dec 18, 2016)

Rich is correct about one direction having the thermal out of the circuit for the start winding. A compromise would be to arrange the connections so that the thermal disconnects start and run in the forward direction since that is most likely what will be used most of the time. I'm not sure though if the start winding can trip the thermal overload if it's stuck on.


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## CluelessNewB (Dec 18, 2016)

Lets say the thermal overload trips when set with the bypassed direction engaged.  The motor then slows down to the point where the centrifugal switch engages.  This then puts one half of the run winding in series with the start winding.  I'm not sure what would happen but I suspect with a light load it would keep cycling on an off and a heavy load would never get up to speed and eventually smoke the motor.  

To the original poster I do believe there is a way to wire KM2 & KM3 to work with this motor.   I suspect it will require small changes to the wiring of KM1 also.  What I  don't know for sure is what F-R is in the original diagram.  The actual connections to contactors Km1, Km2 & Km3 are also a bit of a mystery so I would not be able to tell you which terminals to use.   For these two reasons I am a bit reluctant to post any updated diagrams without knowing for sure what that stuff is.   If you weren't 2700 miles away i would be in a better position to help.


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## mksj (Dec 19, 2016)

The motor contactor has a separate thermal overload. Normally you would not use a motor with its own separate thermal oveload in this control system. Baldor motors tend to be very reliable and durable, so the chance of the centrifugal switch failing in the near future is unlikely. I agree with Rich that the right way would be to wire it per the Baldoe wiring diagram, but when I tried to do map out the wiring diagrams, it would take two 4 pole contactors and more significant wiring changes. The problem is that without being there and mapping things out, it could be a bigger mess and go up in smoke. So I think I would start simple and see how it works, then you can weigh in on the alternate options. Buy a motor that fits the machine wiring diagram without rewiring, rewiring the contactors or going 3 phase with a VFD, etc. F-R seems to be the motor thermal overload that interrupts power through the E-Stop going to the motor contactors.


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## master53yoda (Dec 19, 2016)

markba633csi said:


> Trying to follow along here: So in the original config U and V were the run legs and Z1 and Z2 were the start legs.  U and V were being reversed by the two relays/contactors Km2 and Km3.  Correct?
> What is that FR symbol with dotted line in series with the U and V legs?
> Mark S.





jim18655 said:


> My suggestion for discussion:
> 3-2-5  connected
> 8   to   Z1
> 1 to V
> ...



The only correction would be 1 to U which i think i saw that you already caught.    I agree with the need to connect 5 to the 3-2 connection, in connecting one of the start leads to center of the run winding and  the other to Z1 the  controls are leaving the start windings in phase with the incoming power and reversing the run windings in relation to the incoming power.

The [R] reference points in the U and V wires are the current overloads in the contactors. When they overload thier control switch removes power from the  KM1 primary relay shutting down the motor.  They replace  the thermal over load in the motor.  In the baldor diagram the thermal overload is set to operate on 110 current and would never trip on 240 volt currents In the picture in the beginning post, the diagram from the motor cap the thermal protection from baldor is disconnected and not used in the high voltage connections, they are relying on the controls system to detect overload conditions.

Art B


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## master53yoda (Dec 19, 2016)

this picture has the FR overloads,   the setting should be set to match the Amp draw that is on the motor name plate for 240 volts

Art B


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## markba633csi (Dec 19, 2016)

So for the 220v case, I wonder why Baldor didn't provide a bypass for the thermal? They don't bring out the #3 pin on the thermal (wht/yel)?
Silly guys. Go back to your room.
Mark S.


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## markba633csi (Dec 19, 2016)

Robert (cannon fodder) you still there? I think I have a solution for you:  connect 2 and 3 and 5 together on the motor.  Connect U and V to 1 and 4. Then connect 8 to Z1. If the forward/reverse is backward disconnect 8 from Z1 and connect it to Z2 instead.  Should work.
Everyone else: Jim this is a repeat of your earlier idea. This leaves the run windings being both reversed and thermal'ed externally.  Start winding always gets 110 cuz it's from the run winding midpoint to one end of 220.  If you wanted to be a purist you could short yel and wht/yel on the motor thermal.
Robert make sure you have the ground wire connected to the motor, in addition to the above stuff.


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## jim18655 (Dec 19, 2016)

Look at this, I think it will work if you're so inclined to rewire the contactors. I'm not sure if the contactor numbers are correct and I didn't research which direction they are. The main thing would be to make sure you run the control wire for a direction through the opposite direction contact for an electrical interlock. I also assumed that the top contactor only provides power after a direction is selected.
If it isn't correct I'm sure someone will let me know  .


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## jim18655 (Dec 19, 2016)

markba633csi said:


> Robert (cannon fodder) you still there?...



Pick one:
A. His head exploded form all the answers.
B. Forget about it - he's out buying a new lathe.
C. Sorry I asked.
Vote now!


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## markba633csi (Dec 19, 2016)

It looks to me also that the Baldor thermal receives the same current for either 110 or 220 volt connection; sees only 1 run winding's worth of current in either case.
It's too bad if Robert jettisoned himself- his electrical ignorance was in danger of being diluted 
Mark S.
PS Sorry Robert if us eggheads took too long, it happens sometimes.


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## CannonFodder (Dec 20, 2016)

Hello gentlemen!!!
No, I haven't left.  Weekends are my workweek and I was very busy.  Sorry about the lack of communication.

I can not open jim18655's pdf.  My browser begins to open a new tab, but then disappears.  Can you repost?
I will set up the motor according to Mark's suggestion and get  back to you guys.

You guys have great energy and are a great resource, I appreciate it so much.

I also have a new contact who is going to bring over a Chinese manufactured motor that is perhaps jumpered together in the same fashion as the original motor was (that is, it looks similar to the first photo in this post).

Thank you again, I'll let you know,

CannonFodder (Robert)

P.S.  My electrical ignorance seems to be doing fine, my head is swimming and appears normal in every respect


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## markba633csi (Dec 20, 2016)

Glad to have you back Robert,  we aim to please 
MS


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## CannonFodder (Dec 31, 2016)

Hello Gentlemen,

Just a last note to close out.
The acquired Chinese motor had a junction box identical to the one I took out.  I hooked it right up and it ran fine.  I did need to switch the hot leads as it was running backwards, but it is working great.  

Thanks again for all the time and effort you all gave to my puzzle, it is great that you give this support.

The Baldor will become a 12" or 20" disc sander I believe, or perhaps a combo disc and  belt sander.

Sincerely,

CannonFodder (Robert)


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## markba633csi (Dec 31, 2016)

You're welcome Robert- Happy 2017
Mark S.


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