New member, with lathe motor problem.

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Build and fix
Posts: 5
Joined: Sun May 13, 2018 12:18 pm

New member, with lathe motor problem.

Post by Build and fix »

Hi everyone. I found my way here, while trying to figure out why my 2hp lathe motor won't run.
The lathe is a CQ6230 12x36 on single phase 240V power. The motor is induction with 2 capacitors, and an internal centrifugal switch. 5 wires, including ground, enter the motor terminal connection box. Inside are 6 terminals, and a ground connection. 3 of the terminals are bonded together.
If I spin the shaft by hand, and flip the switch on the apron, the motor tries to spool up, but dies in one second, coasts for a second, then tries again, repeatedly.
The caps are 20uF 450VAC, and 150uF 220/264VAC, both are 50/60 Hz. The 20uF is larger, but I think the 150uF is a start cap.
I have a schematic, but don't fully understand it.
Thanks in advance, for any help.
curtis cutter
Posts: 559
Joined: Fri May 18, 2012 11:46 pm
Location: Curtis, WA

Re: New member, with lathe motor problem.

Post by curtis cutter »

Is the wiring diagram on the motor and if so can you take a picture of it and share?

Where are you from?
Gregg
Just let go of it, it will eventually unplug itself.
John Hasler
Posts: 1852
Joined: Tue Dec 06, 2016 4:05 pm
Location: Elmwood, Wisconsin

Re: New member, with lathe motor problem.

Post by John Hasler »

The 150 is the start capacitor. The 20 is the run capacitor. From the symptoms either both capacitors are bad or the motor is miswired. The cycling behavior indicates that the centrifugal switch is ok.
Build and fix
Posts: 5
Joined: Sun May 13, 2018 12:18 pm

Re: New member, with lathe motor problem.

Post by Build and fix »

I'm in Alberta Canada, posting from my phone.
Haven't used the camera, or tried to send attachments with it yet, still need to figure that out.
The motor plate shows Type YL90-L4
110V/20A 220V/10A, and has 4 configuration diagrams of the 6 terminal block, all with the same letter/number labels, but different bonding configurations. I'm thinking forward and reverse for either voltage. The ground is separate from the terminal block.
Main 240V power enters a control box, containing contactors, connection bus, and a low voltage control circuit transformer, and exits from there to the motor.
I've opened the motor, filed the centrifugal switch contacts, and still the same symptoms.
Voltage test of the 150uF cap, still soldered in, after reinstalling and testing motor this morning, showed 480V, dropping quickly, then slower, with voltmeter connected, and no power to lathe! Reversing terminals of multimeter, set to 500VAC, shows 0Volts.
Checking tonight, V is around 260, unplugged.
Have to go rest my eyes (and head)!
whateg0
Posts: 1114
Joined: Sat Mar 28, 2009 3:54 pm
Location: Wichita, KS

Re: New member, with lathe motor problem.

Post by whateg0 »

I think you're going to have to figure out how to post pics of the wiring. Measuring the voltage at the capacitors isn't going to help at all because it's constantly changing when in use, and when not in use, doesn't matter. Yes, if these are the diagrams, it looks like they are for each voltage forward and reverse. You are applying 240, but is the motor wired for 240? How do you know? We're either going to need pictures or at least a good diagram of your wiring to be able to tell if it's right or not.

Dave
Attachments
0004235_xiang-long-single-phase-dbl-induction-motor-yl90-l4.jpg
Build and fix
Posts: 5
Joined: Sun May 13, 2018 12:18 pm

Re: New member, with lathe motor problem.

Post by Build and fix »

Motor plate is practically the same as your attachment Dave, except my motor plate has 220V, and AC symbol, printed between the 2 lower configurations, and 110V and AC symbol between the upper 2.
Motor is configured like lower left, except V2 and Z1 are not connected. Z2, U2, and V1, are bonded together.
After taking a photo of motor wired to lathe, to get a better view (lathe is close to the wall) I see wire V2 from control box is on U1.
Have to go, I'll post more later.
Bentworker
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Joined: Fri Mar 02, 2012 1:29 am
Location: State of Jefferson

Re: New member, with lathe motor problem.

Post by Bentworker »

Do you have a multimeter capable of reading capacitance?
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Build and fix
Posts: 5
Joined: Sun May 13, 2018 12:18 pm

Re: New member, with lathe motor problem.

Post by Build and fix »

Hi, I don't have a multimeter with capacitance setting, but keeping my eyes peeled for a good deal on one now.
I took some pictures of the wiring, now I have to figure out how to resize and send them.
whateg0
Posts: 1114
Joined: Sat Mar 28, 2009 3:54 pm
Location: Wichita, KS

Re: New member, with lathe motor problem.

Post by whateg0 »

Easiest way to resize after the fact that I know of is to download Irfanview (free for personal use, or something like that).
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Dave_C
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Location: Springfield. MO.

Re: New member, with lathe motor problem.

Post by Dave_C »

Type YL90-L4
Too bad you are not close to me as I have that exact motor sitting in my storage shed and you could have it for free! I took it off my 12X36 lathe when I changed it to CNC.

It would cost more to ship it to you in Canada than the motor is worth and I have no way to crate it up.

If you want to know how it wires up, go to Grizzly.com and look up their G-4003G lathe. From there you can download the manual, go to the back pages and there you will find the wiring diagram for 2 HP 240 single phase and how it wires to the forward reverse switch.

Dave C.
I learn something new every day! Problem is I forget two.
ChipMaker4130
Posts: 187
Joined: Tue Dec 04, 2007 11:00 am
Location: Ivins, Utah

Re: New member, with lathe motor problem.

Post by ChipMaker4130 »

Build and fix wrote: Tue May 15, 2018 11:36 am. . .I don't have a multimeter with capacitance setting, but keeping my eyes peeled for a good deal on one now. . .
Most DMMs have a very limited range of capacitance measurement. Before you buy, make sure the one you intend to get can actually go all the way to 150uF.

Was this motor running for you before? Or did it come to you with this issue? It is not likely that it is improperly wired if it was working well and just suddenly stopped.
Build and fix
Posts: 5
Joined: Sun May 13, 2018 12:18 pm

Re: New member, with lathe motor problem.

Post by Build and fix »

Wiring labeling was wrong, but motor worked in forward direction for years, till the other day.
After making a cord to test the motor plate wiring diagrams, motor works, forward and back!
I had to wire differently, and jumper U1 to Z1, but forward works again.
If I rewire the contactors, I think I can get reverse working, but don't have time right now.
Still not sure what happened, just glad I can turn again.
Thanks for the help guys if nothing else, I know more about wiring, then before.
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