Warco WM250

I had been using my Warco this afternoon for about 40 minutes. I had stopped the lathe to change tools, pressed the start button, nothing, deader than a whole lot of dead things. Now I know nothing about electrickery. I am sure that one of you clever electrickery bods can point me in the right direction to effect a repair.

Good job I have a recently acquired Myford so I could complete the job.

Ok, going to have to do this the hard way...

Is the nvr switch latched on?

Chuck guard in place? can you check the plug fuse?

Edited By John Rudd on 26/01/2017 20:13:34

The only time my 280 failed to start was when the speed control pot on the front went. Try it at full speed as when they go they act more like a switch - all or nothing.

Suppose we should also ask if it is a DC or newer AC motor version.

Fuse in a holder either on the rear of the machine or front panel, one of the unscrew with a thumb nail type.

Does it have a separate E-Stop switch or rely on the No-volt switch ? If it has an E-stop check it hasn't been pressed by accident. [ Don't ask ]

10A if I remember right.

Again as John R has said, chuck guard? guard covering the change gears on the end ?

Thanks Guys, plenty of things to try later on my return from taking you know who shopping, bah. having a brother who was an electrician has not helped but unfortunately I am no longer able to call on his assistance.

Well I have checked all those things suggested and all appear O.K. except the switch does not latch on. I replaced the fuse in the plug with a brand new one but still no life. Is this the switch is defective or something more. For your information the lathe is about 8yrs old so is fitted with a DC motor and is as original. The micro switches on the chuck guard and gear cover are disabled and have been since new without problems. Where do I go to from here?

Dusty,

Does the lathe run when you press the Green button on the nvr switch even tho' it doesnt latch?

If the motor runs, then it suggests a fault with either wiring associated with the latch part of the nvr sw or the nvr switch is defective( coil....)

Report back your findings and we will continue...

Hi John,
I could not find a wiring diagram for the WM250 but I have found this one for the WM180 which I would think would be similar. I don't think you can go any further until Dusty answers your question.

Les.

No the lathe does not run at all. it makes the DoDo look healthy.

Dusty,

Do you have a multimeter/know how to use one?

If you have/can use one, then with it switched to ohms( resistance) with one lead clipped to the Live pin of the plug ( unplug it from the mains first!) can you trace the wiring from there through to the speed control board, where there will be a wire attached to one of the Line connectors....so with the other meter probe connected to the Line connection...does the meter read approx 0.2 ohms?

then repeat with Neutral pin thru to the other Line connector on the speed controller....and report back your findings please....

Oh dear, I started to use my head for thinking rather than somewhere to put my hat. I came to the conclusion that power was not getting to the switch. I replaced the fuse in the back of the lathe lo and behold life, but oh dear a horrible clunking rattle noise a bit like gears not engaged properly. Speed was poor, so I used the speed control , made no difference, no change in speed still the horrid noise, that's when the board tripped out on the lathe circuit. I suspect it is the motor that is causing the noise, but is that through problems with the motor or problems with the electronics?

Edited By Dusty on 27/01/2017 17:14:57

If you suspect that the board may be the cause, disconnect the motor from the lathe.

Follow the wires from the motor to where they are terminate, I suspect a fwd-o-rev switch?

Then connect a household 60watt lamp, mounted in a bulb holder with a length of cable attached.....connect to the terminals where the motor was wired to.

Now, go through the start procedure you use to run up the machine, but with the speed pot at minimum. Then increase the speed pot and observe if the lamp increases in brightness as you turn the pot......if the lamp glows dimly or is at max brightness, there is an issue with the control board......

If the above shows that speed controller appears fine, you will need to remove the motor for further checks.

NOTE.....if you remove any wiring, ensure you mark it to ensure it goes back from whence it came......

John, silly question will that work with a D.C. control circuit, as I said I know next to nothing about electrikery.

Check for sticky brushes and carbon deposits in the motor causing tracking, common fault on these motors.

The light bulb doesnt care what the supply to it is....AC or DC.....

Edited By John Rudd on 27/01/2017 17:44:28

Check out earlier threads. When mine died it was just this resistor. Not pressed fully home. I checked motor with 12v charger.

Well some sort of success it appears the speed control is working O.K. I got the result that John described, the only thing was the NVR needed holding in and started buzzing whilst doing the test.

Dusty,

Do you have a dvm/ multimeter and know how to use it?

If so, you need to trace the wiring to the coil side of the nvr switch.....

The wiring associated with the interlocks that were removed is intact?

Before condemning the switch, its easier to verify whats going in with it first...

It is possible that the interlock switches (Chuck guard, change wheel cover and any emergency stop switches) are wired in series with the coil on the NVR switch. This would mean that the motor would run while the start button was pressed when the interlock circuit was broken but the NVR switch would not latch in. This is the way my Chester DB10G was originaly wired.

Les.

The interlocks first. When I purchased the lathe the micro switch on the change wheel guard was broken (physically} I was sent a new one and this was fitted by someone local who Warco had arranged. He fitted it but bypassed it as he said it is likely to be a source of problems. The chuck guard micro switch is as fitted but the chuck guard is removed leaving it permanently closed. No other switches in circuit. I have acquired a multimeter but have no experience of using it. I have now located the operators manual and lo and behold in it is a wiring diagram.

Edited By Dusty on 29/01/2017 09:50:37