Calling all Sparky's - wiring 1ph drum switch on lathe

[Sarge 3,462]

Ok - I'll be the first to admit it >

I am no Electrician.

 

I can do basic cords, outlets and have installed a few panels (with a sparky buddy to approve/guide) - but that's my limit. Most things I can look at a diagram and figure out on 1ph equipment - but for some reason, I just cannot wrap my half-dead skull around wiring this motor correctly on my son in law's lathe. It was wired to run in one direction only - I suspect that is due to someone that owned it previously couldn't figure it out either, lol. Need both directions functional so I can run some operations to make parts for my own Enco, which is about to undergo some fairly major repairs to worn parts. Without a second and operational lathe - can't repair the other one that is leaking and about as sloppy as a lathe can get, mine has been badly abused.

 

Here is what he's got - older Craftsman 6" lathe. Basically, the late 50's version of the Atlas/Craftsman. Single phase Craftsman general purpose 1hp motor - dual voltage. Furnas R44-C drum switch with Forward/Off/Reverse positions. From what I've read for the last 2 wks, most setups on single phase motors require the double "L" configuration in the drum switch - this one is set up differently and by the diagram in the cover can seem to handle both single and three phase motors. Where I'm really lost is inside the motor itself where the wiring is on the board terminals and how the wiring diagram is laid out on the motor tag.

 

Here's what we have -

 

Craftsman 1hp motor - Model 113.12151 Cat. 1215

 

 

 

This is the Furnas R44-C drum switch - need to set this up to run the motor on 1ph 115VAC. The switch handle is oriented at the top of these drawings.

I think the starred note on the lower right drawing for the split phase motor use is for a jumper wire?

 

Switch contact layout and function -

 

 

As far as I can tell - the diagram that relates to the motor he's using is the split phase/1ph diagram in the corner of the label. I should have grabbed a pic of the motor's internal terminal connections - but I can get that if we need it. Need to figure out which terminal in the drum switch gets the hot lead connected from the switch diagram and which wires to extend to the drum switch from the motor to get it right. I almost believe a jumper will be necessary to make the reverse function, but not sure of that?

 

Found a picture of the plain R44 switch -

 

 

Almost all the machinery forum threads I've found had used Photobucket and most of those links are either dead or the photos are missing, which is no new thing to anyone. This motor does have a thermal reset switch installed on the case, btw - not sure if that is relevant or not.

 

Any of our resident electricians have a clue on this thing? I'd like to start tearing my lathe apart so I can get it fixed - which, in turn - is needed to get the Atlas Clausing drill press work finished so I can clean up my shop and move forward onto some of the tractor projects and parts. All of this reading/searching has left me with a migraine lately - think I let the magic smoke out my head trying to figure this thing out.

 

Sarge

 

 

 

 

 

[meadowfield 2,545]

start by identifying the end of each winding, if you have a DVM them just look for the lowest resistance pairs. If you don't then putting 12v in line with a bulb through them will show them.

 

The remaining pair should be the motor run capacitor.

 

The motor is 1hp single phase induction, so reverse is swapping the capacitor leads that generate the lag required for an induction motor to spin.

 

Without really seeing and being able to measure - it's really hard to help!    plus that diagram on the motor is a little vague...

 

 

[Sarge 3,462]

That's exactly what has me so stumped,  that wiring diagram is pathetic at best. I did get a picture of the terminal plate in the motor.

 

 

The way the terminals are located in the plate is why I'm confused. I only have 4 wires to work with  - red/white/black/brown. Tried using my DVM to find the main pairs of each winding,  but that test didn't make any sense,  as some were ringing zero. Maybe it's due to how the neutral side is wired? The tag shows red and black as being swapped for the direction of rotation. Not sure,  but maybe I should try testing each terminal for continuity to ground? The extra terminals located next to each other don't all show continuity,  either - that really has me scratching my head.

 

I know the run winding should be a low ohms reading and I did get one pair to read that way. Came out to 3 ohms. The other pair was around 27 ohms, but kept changing on my DL389 Phoenix meter. I hate auto-ranging meters for stuff like this and should do it again with a regular analog version. Since this motor is dual voltage,  is that why the terminals are so odd?

 

Wish a buddy of mine wasn't tied up with things at home,  he'd have it running in short order if he could get here.

 

Sarge

Edited February 19, 2019 by Sarge
missing details

[bc.gold 3,399]

You have to remove the motor leads from the motor back plate, extend these to your drum switch as shown in this diagram. As you can see from the wiring diagram attached to your motor the red and black being referanced have the spaded ends located at terminal numbers 2 and 5

 

On a side note, once the motor is up to speed the contact points on the start winding are opened via centifical force a common failure of small electric motors starting under load is for the contacts to burn out and these are easily replaced.

 

Worse case scenario is that the contacts have welded together and have burned out the start winding's.

 

 

 

SARGE this is the schematic from the tag on your motor. the red and black leads are the start winding's.

 

 

Edited February 20, 2019 by bcgold

[Sarge 3,462]

I'm aware of how the start windings work and they are easily identified by their smaller gauge wire - yes, red/black is the starter. The contacts on the centrifugal switch were pretty pitted, mostly from recent and past attempts to wire this thing correctly to the drum switch that was bolted to the lathe. Craftsman used 2 different types of 6-contact switches - the "L" configuration that you show in your drawing and the parallel type R44 that is used on this lathe's current setup. I did find a drawing yesterday and a diagram that shows using a jumper to make the current switch work.

 

The top, left-hand diagram applies to this type of motor - switch handle is at the top

 

 

One part I don't understand inside the internal parts of the motor is the 4 poles and how they are wired. None of the pole wires are grounded to the case, nor shorted out to each other - the winding pairs ohm out to the same relative reading on the meter. With the additional thermal reset/overload switch - there are some oddities as to how they wired the poles to the terminal plate. From the ohm testing and finding which pairs are together as a winding, these are the colors I have -

 

red/black - starter

blue/white - main winding

yellow/orange - main winding

 

Throwing the reset switch into the mix is where I'm stumped at the moment - I don't want to defeat it but it also 3 terminals on it. One has blue and white on the heavier terminal, one other uses brown and the 3rd is white again. Both the white and brown wires are routed to the terminal plate, but the blue is part of the main winding. I should have grabbed a picture of it along with how it was wired to the terminal plate, just seemed a little odd in how it was done compared to other motors I've worked on in the past. 

 

I see by the drawing you show that both the run windings are wired into a series configuration and routed up to the drum switch with only 2 wires. Are there any rules about polarity that would affect the phase shift in the 2 sets of windings when doing it this way?  I spent most of yesterday reading and watching tutorials about how the windings are laid out, phase shift and the timing of the field as well as how the wiring into control switches is done. I never did find any exact information about this particular motor other than one drawing from the Vintage Machinery forum site and that drawing used the "L" configuration switch versus the R44 multi-configuration switch that is on the lathe currently. After studying the drawing you've shown - that drawing makes sense when used with a jumper wire between the #3 & #5 posts on the drum switch. But, how can the thermal protection reset switch be incorporated into this configuration when it has 3 terminals? I understand that in order to protect the motor, those thermal reset switches must be able to read resistance and heat buildup from overload conditions - or, at least that's what I take away from all of yesterday's reading.

 

I feel like an idiot - I sat here yesterday with the terminal end bell removed, a bunch of wires sticking out, 2 different ohm meters and seven different drawings on paper - along with several more drawings open on the computer. It finally overloaded my own internal circuits and I had to give up for the day - my eyes got to the point they wouldn't focus anymore. I used to be able to figure this stuff out if I have the diagrams or through simple testing and notes - but my vision is really getting in the way now with this eye condition that cannot be repaired nor corrected. Been trying to hunt a local guy here in town that works in a mill as the site electrician - I know his main thing is motors and he should be able to handle this thing easily, but he's been gone somewhere lately and hasn't been around.

 

Sarge

[Sarge 3,462]

Dug a little deeper today when I had the time to really study the thing further. Interesting how the protection switch is wired into both the run and start windings.

I took the time to map out the connections from the terminal board - as well as the Klixon K5A protection switch. I numbered the back side of the terminal insulator plate to better understand how it is wired.

 

T1 - white lead to P3

T2 - white lead to P1 & red lead to start winding

T3 - brown lead to P2 & orange run winding

T4 - yellow & white leads to run winding

T5 - black lead to start winding

 

Here's what it looks like -

 

 

 

 

Any clue on how that protection switch can be retained to protect the motor's wiring?

 

Sarge

 

[bc.gold 3,399]

You may have to take a short sabbatical from this site then visit smokestack to get the information your seek.

 

 

 

Edited February 22, 2019 by bcgold

[bc.gold 3,399]

Your start leads connect to each side of the center poles on the drum switc in the begging do not concern with color then your run leads go to the outside poles then on the opposite side on each end pole L2 and L2, if the motor runs in an undesired direction on start up swap over the two center leads. The chassis ground connections should be obvious.

 

The hand drawn diagram I posted above is correct, you'll have to extend the start and run wires coming from the motor so that they'll reach the drum switch. And stop trying to figure out the internals of the drum switch and put your trust into the schematics.

 

 

Now for a bit of humor, years ago I used to do a bit of sub contracting for a water well and pump company. One day was called up to do a new install on a shallow well pump, everything went without a hitch.

 

 

Got s call the very next day from a very irate manager who was now telling me in so many words that I would be going back the the customer I had previous installed the new pump the day before had quit working and that I would be doing it on my dime.

 

I stop in at the shop a grab a new pump to take with me should it be needed, on inspection what I found was that a slug had managed to find its way into the motor via the open end plate causing the motor start contacts to remain closed after starting.

 

Burned out the start winding.

 

 

 

 

 

Edited February 22, 2019 by bcgold

[Sarge 3,462]

The drum switch is a problem - it is not configured the same as the one in the hand-drawn diagram. Most of what I have found for this type of application came from the Vintage Machinery forum - that drawing is shown on that site as well as many others, including SmokStak.

 

I'll have to head over to the Vintage Machinery forum as well as the Garage Journal or maybe even the Practical Machinist site - most have resident electrical guru's.

 

I have found some of the oddest critters in electrical devices over the years - salamanders being the most adventurous in getting into trouble.

 

Thanks,

Sarge

[bc.gold 3,399]

Single phase capacitor start motor, hope this helps

 

 

[Sarge 3,462]

The terminal plate in the motor is where the problem started - someone else had been into this thing before and changed how it was wired. That change led to the diagram making zero sense and why I was so confused about any drawings that otherwise would apply to this motor. I finally figured out the pole wiring last night and got it wired so they work together instead of against each other - polarity on these matters. With that done, I got it tied together properly at the terminal plate and tested the motor - works perfectly. I'll take it over to the lathe later today and wire it up to the drum switch and get it installed. We'll spend the rest of this weekend working on going through the lathe and get it properly oiled and cleaned so it can be put into service. Pretty excited to finally be able to make the necessary parts for my Enco and get that sloppy bugger back into proper working order again - I've been putting up with it for far too long.

 

It took 3 drawings to apply to this dual voltage motor - this is the correct diagram to tie the poles together so they don't fight each other

 

 

So, using a combination of this motor drawing and ignore the drum switch wiring (wrong drum switch - this lathe has an R44-C)

 

....and use this drum switch diagram for the R44 series switch -

 

 

Sarge

[Sarge 3,462]

Took the time yesterday afternoon and went over to the shop to install the motor and wire it up to the switch. All done now except to go through the little lathe and get everything properly oiled and all adjustments performed. The motor works flawlessly and starts/runs far better than the way it was wired previously. Got lucky and nailed the direction wiring on the first attempt, for once. Son in law (Matt) hadn't told me before but the couple of times they tried running it prior to the re-wire it was putting an odd hum back into the garage lighting - that was most likely from the mistake on the terminal plate and putting the two sets of main run windings out of sync with each other. I haven't tested the line supply yet to make sure there is no induced hum into the wiring - but it should work fine compared to how it was done previously. Even on 115 volts - motor starts and runs as it should now.

 

Time to start working on the Enco and repair some of the slop in the carriage and repair those head bearing seals - it will be nice to have that thing working properly for once.

 

Sarge