# Wiring a new drum switch to my original MW motor



## zayd (Sep 12, 2020)

Hello, folks.

I'm hoping some of the electrical specialists here can help me out.  I'm fairly clueless on motor wiring, so this is basically the last thing between me and getting this Logan/MW 10x24 up and running.

A little background: I picked up this Logan/Montgomery Wards lathe (I believe it's the 84TLC-2130) from a smaller machine shop last year.  It had clearly been stored for a long time, but was fairly complete and largely original.  I completely disassembled it, cleaned everything, assembled it, lubed everything that needed it, and leveled the lathe.  It's back together now, but I've saved the wiring (my nemesis) for last.

It came with the original, 1/2hp dual voltage 1ph Wards motor, capacitor start.  Here's the best photo I could get of the faded motor plate:




There are six leads coming out of the motor, all red wires with original labels.  As best as I could tell and assuming no labels fell off, this is how they're labeled: 2, C 5, J 6, 7, 8, and E.

It was missing the front half of the original switch, so I bought a new Dayton 2X440A reversing drum switch to use instead.  Here's the diagram on the inside of the switch cover:




I don't believe the original Logan wiring instructions are a lot of help since this is not an original switch, but it is  here.

http://lathe.com/wiring_diagrams.htm 

(I think I have the "1105" motor on the right side of the page).

The bottom line is that I'd like to wire it 110V, but I'm lost on how to interpret these diagrams.  Any help would be fantastic.

Thank you!

Zayd


----------



## markba633csi (Sep 12, 2020)

Does it say anywhere on the motor "swap wires so and so to reverse"?  If not we need to do a bit of testing with a multimeter
-Mark


----------



## zayd (Sep 12, 2020)

Hi, Mark.  I did not find those instructions on the motor like I'd typically see.  I checked under the peckerhead cover as well.  I'm handy enough with a multimeter, so I'm good with that approach.  Thanks.


----------



## Nogoingback (Sep 12, 2020)

zayd said:


> Hello, folks.
> 
> I'm hoping some of the electrical specialists here can help me out.  I'm fairly clueless on motor wiring, so this is basically the last thing between me and getting this Logan/MW 10x24 up and running.
> 
> ...




Welcome to the group zayd.  Sorry, I can't help with the wiring, but we have plenty of folks here that can.  We would like to
see some pics of your lathe when you can get to it.


----------



## wa5cab (Sep 12, 2020)

****************************
I don't believe the original Logan wiring instructions are a lot of help since this is not an original switch, but it is here (I think I have the "1105" motor on the right side of the page).
*********************************

Try again to show the original hookup instructions.  They did not show up in your post.


----------



## zayd (Sep 12, 2020)

Robert, the instructions were linked above but you're right, I should just include the image here also:

View attachment 336645


----------



## zayd (Sep 12, 2020)

Nogoingback said:


> Welcome to the group zayd.  Sorry, I can't help with the wiring, but we have plenty of folks here that can.  We would like to
> see some pics of your lathe when you can get to it.



Thanks!  Forgive the hypocrisy; I'm also usually quick to look for photos.  Here's a hasty one.  The chip pan was a later find.  There are also a few bits not pictured, like the 3- and 4-jaw chucks, steady rest, and a couple other little things.  Overall, I'm only short a parting tool holder and some good HSS or carbide bits.


----------



## wa5cab (Sep 12, 2020)

Incidentally, with all of the different drum switches that are or were available, 98% of them are built one or the other of two ways.

The link to the Logan site was corrupted but I think that I fixed it.  For some reason that I didn't look into, the Attachment  336645  is either missing or corrupt.  But if you hover your mouse pointer over the URL now shown, it brings up the "Motor and Switch Wiring Diagrams" on the Logan site.

I think that you are probably correct in saying that your motor is the 1105.  But unfortunately, as the motor that you have is not labeled the same as the 1105,  you are going to have to do some exploring with the Ohmmeter.   I will write that up next.


----------



## Nogoingback (Sep 12, 2020)

zayd said:


> Thanks!  Forgive the hypocrisy; I'm also usually quick to look for photos.  Here's a hasty one.  The chip pan was a later find.  There are also a few bits not pictured, like the 3- and 4-jaw chucks, steady rest, and a couple other little things.  Overall, I'm only short a parting tool holder and some good HSS or carbide bits.
> 
> View attachment 336646



Nice looking lathe.   Any idea what the bracket on the carriage was for?


----------



## wa5cab (Sep 12, 2020)

First, make a safety check.  I don't know what kind of ohmmeter you have so if any of the following steps can't be done, just skip them.

Set the +/- switch to +
Set the mode to Ohms.  Set the range to the highest value that the meter has, such as R X 10K
Connect the negative meter lead to the frame of the motor.
Momentarily touch the positive lead to the motor frame.  Reading should be zero or near it.
Connect the positive lead to each of the 6 wires, one at a time.  No wire should show less than Infinity.  If any do, note the wire number and resistance reading and proceed to the next wire.  When finished with all 6, if any showed continuity to the frame, stop and report the results.  If not, proceed.

Connect the negative meter lead to 2.  Connect the positive lead to the other wires, one at a time.  Only one wire should show less than Infinity.  Note the wire number and resistance reading.  If necessary, temporarily switch the ohmmeter to a lower range in order to get an accurate reading.  Switch it back to the highest range before proceeding to the next wire.  If a second wire also showed continuity to 2, record that and the resistance.  Note that one pair of wires (the START circuit) should show momentary resistance between the wires and return to infinity.  If you find such a pair but it does not return to infinity, you have a bad start capacitor.  Note that but carry on with the test.  When all have been checked for continuity to 2, move the negative lead to C5 (unless it was the one connected to 2, in which case, skip it).  Proceed to check and record the resistance between each of the remaining wires.  Report results here.


----------



## markba633csi (Sep 12, 2020)

Hi Sayd, once you have performed Robert's tests above you need to phase the two run windings.  One way to do that is to make two tests under power, connecting one run winding at a time in parallel with the start pair and noting the rotation.  The goal  is to be able to connect all three pairs in parallel, and each run winding connected to give the same rotation, rather than having the two run windings out of phase and fighting each other.
-Mark


----------



## zayd (Sep 12, 2020)

Nogoingback said:


> Nice looking lathe.   Any idea what the bracket on the carriage was for?



I wish I knew.  I couldn't find anything like it in the catalog.  It certainly looks like factory paint on it.


----------



## zayd (Sep 12, 2020)

Robert and Mark -- thanks for the great guidance.  I will run through this routine and report back with results (or more questions!) tomorrow.


----------



## markba633csi (Sep 12, 2020)

Once you have identified the motor wires we can help you wire the drum switch- first things first
-Mark


----------



## wa5cab (Sep 12, 2020)

And running the motor with only the START and one RUN winding at a time is better that the other method which Murphy's Law pretty much guarantees will exercise your circuit breaker.


----------



## zayd (Sep 13, 2020)

wa5cab said:


> First, make a safety check.  I don't know what kind of ohmmeter you have so if any of the following steps can't be done, just skip them.



I'm using a cheapie Craftsman multimeter.



> Set the +/- switch to +
> Set the mode to Ohms.  Set the range to the highest value that the meter has, such as R X 10K
> Connect the negative meter lead to the frame of the motor.
> Momentarily touch the positive lead to the motor frame.  Reading should be zero or near it.



Performed this and got the expected result of zero.



> Connect the positive lead to each of the 6 wires, one at a time.  No wire should show less than Infinity.



Performed this and got no continuity from the motor frame to any wire.



> Connect the negative meter lead to 2.  Connect the positive lead to the other wires, one at a time.  Only one wire should show less than Infinity.  Note the wire number and resistance reading.  If necessary, temporarily switch the ohmmeter to a lower range in order to get an accurate reading.  Switch it back to the highest range before proceeding to the next wire.  If a second wire also showed continuity to 2, record that and the resistance.  Note that one pair of wires (the START circuit) should show momentary resistance between the wires and return to infinity.  If you find such a pair but it does not return to infinity, you have a bad start capacitor.  Note that but carry on with the test.  When all have been checked for continuity to 2, move the negative lead to C5 (unless it was the one connected to 2, in which case, skip it).  Proceed to check and record the resistance between each of the remaining wires.  Report results here.



Alright, with *negative connected to 2*, I got:

Wire 6: zero
Wire 8: infinity
Wire C5: zero
Wire 7: infinity
Wire E: zero

Since this was a little different than what we expected, I ran the same exercise for all the wires, reported below.

*Negative to C5, positive to:*
Wire 6: zero
Wire 8: infinity
Wire 2: zero
Wire 7: infinity
Wire E: zero

*Negative to 7, positive to:*
Wire 6: inifinity
Wire E: infinity
Wire 2: infinity
Wire 8: down to 50 ohms then slowly climbed up from there towards infinity
Wire C5: infinity

*Negative to 8, positive to:*
Wire 6: infinity
Wire E: infinity
Wire 2: infinity
Wire C5: infinity
Wire 7: slow drop to zero, then slow climb towards infinity

*Negative to E, positive to:*
Wire 6: zero
Wire 8: infinity
Wire 2: zero
Wire 7: infinity
Wire C5: zero

*Negative to 6, positive to:*
Wire E: zero
Wire 8: infinity
Wire 2: zero
Wire 7: infinity
Wire C5: zero

So I've learned from your notes above that it looks like 7/8 would be my START circuit.  I'll wait for further instructions!  Thanks for this.

Zayd


----------



## markba633csi (Sep 13, 2020)

OK here's what I think is going on:  7 and 8 are indeed the start circuit, so that's good.  As for the other readings I suspect you may have a short between windings, or the two run windings are connected in parallel already internally, which is seeming less likely since they brought out 4 wires.  How low does your meter read on ohms?  Does it have a Rx1 or Rx10 range?  The run windings should measure something like 6 to 8 ohms each which in parallel would read 3 to 4 ohms or so.  See if you can get some meaningful low ohm readings and report back

-Mark
Unfortunately, a new motor may be in your future


----------



## zayd (Sep 13, 2020)

markba633csi said:


> OK here's what I think is going on:  7 and 8 are indeed the start circuit, so that's good.  As for the other readings I suspect half of the zeros are true zero (connections) and half are low ohm readings thru the windings,  so the two run windings are connected in parallel already internally. Why they brought 4 wires out I don't know yet.  How low does your meter read on ohms?  Does it have a Rx1 or Rx10 range?
> -Mark



Mark, I set it at 2000k for those readings.  I can get down to 200 ohms.  Should I repeat the exercise at that setting or are there specific wire combinations I should check?


----------



## markba633csi (Sep 13, 2020)

I corrected my post after thinking about it for a while- you may have shorted run windings- try measuring again at the 200 ohm range and see if you can differentiate the zero readings.  But the signs are not encouraging.
Be sure to re-zero your meter when you change ranges, and that the wires and test probes are clean and give stable readings
-M


----------



## wa5cab (Sep 13, 2020)

I'm afraid that Mark is correct.  It ain't luckn gud.  I guess that at this point I would repeat the check with the ohmmeter set to its lowest range..  But regardless of what you find, you or someone is going to have to pull the end bell off of the end with the wires coming out.  And figure out what's going on.  What you should be seeing (ignoring #7 and #8) is between one wire and two others, infinity.  And between that one and the fourth wire, 4 to 8 ohms.  Even if you find that you can differentiate between the wires that are tied together and the other two that are also tied together at the other ends of the two run windings, you would potentially be smoke testing your breaker to apply power to the motor.

If you feel comfortable with pulling the end bell, go ahead.  If you don't, take it to a motor rewind shop and let them fix it.  

Regardless, when it comes time to connect to the reversing switch, the circuit that you want to use is the one called split phase.  Pretend that one of the windings shown is the two run windings properly connected and the other one is the start winding with the normally closed switch and the start capacitor just not shown.  The motor on the drawing called Single Phase I never saw one like before.


----------



## zayd (Sep 13, 2020)

Thanks, Robert.  This could very well be the reason the lathe was retired in the first place.  I am good opening the motor; I'll take a closer look to see if that's possible.  Worst case scenario, I need a new motor.  I do have a 3/4hp 3ph motor sitting idle and a VFD that I just pulled from another machine, so that may be a good match-up to give me some more finite speed control.

I measured again in the 200 ohm range.  I checked and rechecked connections to ensure I had good contact.  All the non-infinity numbers below are new:

*Negative to 2, positive to:*
Wire 6: 1.6
Wire 8: infinity
Wire C5: 0.8
Wire 7: infinity
Wire E: 1.6

*Negative to C5, positive to:*
Wire 6: 1.8
Wire 8: infinity
Wire 2: 0.7
Wire 7: infinity
Wire E: 1.8

*Negative to 7, positive to:*
Wire 6: inifinity
Wire E: infinity
Wire 2: infinity
Wire 8: this time, instantly down to 160 then immediately back to infinity
Wire C5: infinity

*Negative to 8, positive to:*
Wire 6: infinity
Wire E: infinity
Wire 2: infinity
Wire C5: infinity
Wire 7: this time, instantly down to 134 then immediately back to infinity

*Negative to E, positive to:*
Wire 6: 0.5
Wire 8: infinity
Wire 2: 1.6
Wire 7: infinity
Wire C5: 1.8

*Negative to 6, positive to:*
Wire E: 0.5
Wire 8: infinity
Wire 2: 1.6
Wire 7: infinity
Wire C5: 1.8


----------



## wa5cab (Sep 13, 2020)

Either pull the end bell and see what is inside or take it to a shop.  

I'm going to dinner.


----------



## markba633csi (Sep 13, 2020)

My vote is to use the 3/4 hp motor and vfd, variable speed is a wonderful feature to have on a lathe
I think it's not really worth opening up the other motor, unless you are curious
Even if you were to power it up it may overheat and/or not deliver full power- sorry
-Mark


----------



## wa5cab (Sep 14, 2020)

I looked back up the thread and don't see any mention of a 3.4 HP 3-phase motor and VFD drive.  But if you do have one and have the proper AC supply to run it, that is certainly an option and probably your least expensive one.


----------



## zayd (Sep 14, 2020)

markba633csi said:


> My vote is to use the 3/4 hp motor and vfd, variable speed is a wonderful feature to have on a lathe
> I think it's not really worth opening up the other motor, unless you are curious
> Even if you were to power it up it may overheat and/or not deliver full power- sorry


I think you're right, Mark.  The VFD is a little overkill at 3hp, but I can always get a smaller one in the future if I need to repurpose this one elsewhere. Better than just letting it sit.


wa5cab said:


> I looked back up the thread and don't see any mention of a 3.4 HP 3-phase motor and VFD drive.  But if you do have one and have the proper AC supply to run it, that is certainly an option and probably your least expensive one.


Robert, I just mentioned the VFD in my last post.  It became available just yesterday, so it's now an option to run this lathe.  I was hoping to get the original motor going, but it doesn't seem viable or cost-effective at this point.

This was my first time diagnosing a motor at this level and I learned quite a bit doing it.  My gratitude to you and Mark for the guidance through the process!  Tremendously helpful.


----------

