3 phase motor wiring question

My 5914 Clausing lathe came with a 3 ph, 2 hp motor. While rebuilding the lathe & motor, I managed to cut thru one of the leads without
severing the insulation. Mighty neat trick that I could never duplicate if I tried. Upon reassembly the motor had not power and rumbled (actually shook the lathe). Not finding the problem, I bought a much lessor quality 2hp, 3ph replacement motor from my local junk/ slavage/industrial equipment dealer. The replacement motor did not have any leads so I cut the leads off of the Clausing lathe motor about 1 inch from the windings and reused the leads on the replacement motor. Thats when I discovered the problem with the lead and realized that I had cut the leads off of an otherwise perfectly good motor (a much quieter, smoother running motor). I set the motor parts aside (7 or 8 years ago). I finally have some time to attend to misc projects and want to reattach leads and reassemble the motor and eventually swap out motors.
THis motor is a 9 lead WYE configuration. I will never have need/ ability to run this lathe on 440v and I can not imagine a senario (sp) where in the future this lathe would ever be placed into service for anything other than personal/hobby use as now. For low voltage operation, leads 4, 5, 6 are connected together, L1=1+7, L2=2+8, L3=3+9. Is there any reason that I should not make all the junctions (where I cut the leads off next to the winding) and only run 3 leads out of the motor?
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On Nov 14, 12:14 pm, snipped-for-privacy@c3net.net wrote:

Good idea. This is not uncommon.
dennis in nca
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On Nov 14, 3:14 pm, snipped-for-privacy@c3net.net wrote:

Just a suggestion, and I do sometimes get myself into projects such as yours. The correct connections to 3-phase motors are often very confusing.
Before connecting anything, I would first use a multimeter to map out all of the leads and precisely what they connect with on the motor windings. Find out what individual field winding the leads connect with. Next their winding polarity (somewhat more difficult to explain, I use a pocket compass in connection with a 1.5-Volt battery, but somone else may have a better explanation or method to determine the polarization of the windings. The trick here is to determine the winding connection polarity so that once the windings all pull in the same direction. If not, you have one of the field winding revesed, and that could explain your problem.
Just a long shot, but do you actually have 3-phase electric service available at the location you are running the lathe? I know that this question sounds silly and is not intended to be insulting, but still I have been called into several situation in doing favors from freinds, and found that they were tying to connect a single phase supply to run a 3-phase motor, and that simply is not going to work. I assume that is not true in your case, in which I would search for a reverse polarized field winding in the motor.
Harry C.
p.s., Never overlook the obvious solution. Recently, my wife came to me at 7:00 am one recent morning, telling me that her precious Cuisinart grinder that I had repaired for her the week previously, would no longer run. So I came staggering down from the morning shower still dripping and asked her the simple questions. Had she put on the jars in the proper orientation, becuase the Cuisinart won't run unless properly assembled. Yes. Had she pressed down on the food shoot a bit, so the pressure interlock would engage. (She was attempting to grind up chedder chese chunks into shred for a lasanga dish. I looked at here somewhat puzzled and than suggested I try, given that I had replaced the motor power microswitch only a week previously. Same result. Now this was around 7:00 am where I am not arguably at my brightest. I was for a bit stumped, because I could hear the power microswitch clicking, but nothing. Now here is where technological clerness enters the picture as well as bit of humanity. At that point I happend to notice that the Cusinarts wall plug was laying next to the machine on the kitchen counter. So, I plugged it in and the machine worked perfectly, grinding a full pound of cheddar cheese into fine shreds, which emerged in about 20-seconds. (You get the picture, but here is what you likely don't expect.)
My wife loves here Cuisinart, as all women do, and the damn think has rested on my basement workbench for nearly a year waiting for a replacment microswitch (part lazy, and part because those exact replacement microswitches can be hard to find. After nearly a year in the 'man cave' it emerged fully functional. The bride of 49 years was delighted and began to use it every single day for some purpose or another. Now on the one fateful day, here is where the displomacy comes into the picture, I simply told my wife after plugging the machine into the outlet, that the problem must be still due to a flakey microswitch, restored operation, and went back to bed for another hour. I suppose, acts like this have kept us together for 49 years of marriage, and God willing, we will celebrate out 50th on next July 11th.
Sorry, but us older guys tend to allow our focus to drift during a post.
At any rate, I hope that the technical content of this post will be of help to you.
Harry C.
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    [ ... ]

    You can do this if you do two things:
1)    Leave a note on the inside of the wiring box lid about what you     have done.
2)    Crimp insulated ring terminals on each wire, and mark each wire     so you can tell its number -- then slide heat-shrink insulation     sleeving over each bundle of wires, connect the wires together     using a screw of appropriate length though the ring terminals,     including one on the wire going out of the motor, and then     heat-shrink the sleeving over each group to insulate it     properly.
    This way -- it is still possible for a subsequent owner to use the high voltage mode if he so desires -- or if the local codes shift so you can get 480V three phase in your home shop more easily than 240V three phase.
BTW    Are you sure that you can currently identify all of the leads     by number after they have been cut so short? Are the numbers     perhaps stamped on the wires? I've seen mostly dual-voltage     motors with the identifying numbers being aluminum or copper     sleeves crimped on the wires near the ends -- and thus you lost     the markings at the time of your cutting. If so, you may have     to make multiple tries to get the windings right, and having     them held by screws allows you to re-do them a lot better than     soldered joints inside the motor.
    Good Luck,         DoN.     
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The leads are marked every inch or so, T1, ...T9 (marking in the insulation). All but one of the lead stubs was clearly identifiable.

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snipped-for-privacy@c3net.net wrote:

My Clausing 6903 had the wires terminated in flex conduit which caused me a great deal of grief until I found where. It was terminated 460v.
I spliced extensions and brought out all the wires to the starter panel (yes, mine has a starter panel).
If you do wire them down at the motor, do what Don suggested and put a note for the next guy.
Wes
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