Warco WM250

Dusty,

Can you confirm how many terminals there are on the nvr sw please....?

From the drawing, it shows 4 are marked as 13,14 and 23,24. These terminals may have blue and brown wires attached....the wire marked 10 is what colour? This is the free end of the relay coil and is connected usually to any interlocks...

Could you repeat the test, but connect the multimeter to terminals 14 and 10...... But this time do not depress the Green button.....

Can you just confirm what range the multimeter is set to as I have a number of options for ohms ie. 20k 200k etc

I am working under great difficulty as non of the terminals are marked with a number. It does not help that I am having to work through the hole that the switch plate has vacated, I am unable to get to the back of the lathe due to its proximity to the wall so cannot access the control boards. As far as I can see the only wires going to the micro switch are red. Part of the problem is the markings are very faded and yes there are 5 terminals two on which are connected to the forward and reverse switch.

Dusty,

Set the meter to the 20k range.....

"I have never used the speed control at minimum for starting and stopping. I have just gone through the operators manual and surprise, surprise nothing about that."

Dusty - I'm not surprised at your puzzlement because as you remark, that advice is NOT in the manual. However if you look at the ringed text in the photo scanned from my WARCO WM-16 mill manual you wil see the start/stop caution. WARCO have verbally advised me that the same procedure should be applied when using the lathe.

I can only assume that the warning was an accidental omission from the lathe manual.

Rik

John,

I have repeated the test using terminals 10 and 14 well as far as I can ascertain they are the right terminals. I get no readings whatsoever. The wire from terminal 10 is blue and goes to terminal 10 on the for/rev switch the return from 9 goes to terminal 24. Wires from terminals 24 and 14 are black and those from 23 and 13 are red. I have taken the precaution of ordering the NVR switch. Where to now? I had been using 20k range anyway but I thought I better check

Hi John,
On the schematic kindly posted by Michael I think there is a label missing on the NVR for the free end of the coil. I suspect that you thought that 14 was the free end of the coil. The free end of the coil is A1 and is a smaller spade connector than the other four.

Les.

Les,

Yup, I can see that the free end of the coil isnt annotated on the drawing, but it does have wire 10 attached...ergo I asked Dusty to check for coil resistance between 10 and 14.... ( I think...?.?) which ought to be the internal ( cold end) connection back to Neutral....what is confusing is that there is a contact in the box where the F/R switch is....now is that an integral part of that switch or is it part of the interlocks?( no interlocks shown on the drawing?) If its part of the F/R switch, then that could be faulty, if it is then Dusty will have a job on his hands fitting a new one!.....

Dusty, can you check that you have continuity between wires 9&10 when the F/R switch is operated? That is zero ohmsso use the lowest Ohms range..(200?? ) on the meter....

Edited By John Rudd on 31/01/2017 15:34:42

Thanks Les

Yes that's what I found. and that's what I used. I think the wiring and the diagram are approximations to one another If you know what you are doing that's O.K. but as you can see John is taking me through step by step and I still feel as if I am blindfolded.

Which bit of the multimeter do I use for that?

Les,

Thanks for pointing out the smaller connection.....its all too easy to assume when addressing someone from afar...

Now if the wiring were colour coded in accordance with mains wiring, things might be a bit easier...

Hehehee..looks like I was writing while you posted....ermm lowest Ohms range .....for continuity....should read zero, nada, 0......give the switch a good waggle too, just in case there is any crap on the contacts...

Dusty, do you live near Hull? I could jump in the car and come over.....

Edited By John Rudd on 31/01/2017 15:42:15

Tied that and the only reading I got was the1 that shows when set to ohms. No I be an Essex boy, You know Essex born Essex bred strong in arm weak in the head.

Edited By Dusty on 31/01/2017 15:49:56

How confidant are you doing a bit of wiring?

remove the wire marked 10 connected to the small tab on the nvr switch and insulate it so it doesnt cause a problem...take a piece of thin wire, bear the ends, connect one end to the now vacant terminal on the nvr switch, connect the free end to terminal marked 24 on the nvr switch.....

Make sure everything is safe, plug back into mains and see if the nvr switch latches in when you press the green button.....( make sure speed is set to zero....)

If the nvr now latches it looks like the F/R switch is broken........

Hi John,
I think the contact on the forward / reverse switch is an interlock. I think it will be closed in the forward and reverse positions and open in the middle (Off) position. This will prevent switching straight from forward to reverse. as the reversing switch passes though the off position it will cause the NVR to drop out. (My theory)

Dusty, Is your multimeter analoge or digital ?

Les.

Edited By Les Jones 1 on 31/01/2017 15:59:46

Les,

Yup, I concur, although the drawing doesnt show any other interlocks, what was confusing was that Dusty had said that any chuck guard/door switches were wired out......

I'm guessing his dvm is digital....( wild stab in dark ....)

Hope fully if the above jury rigged wiring works it will prove the switch.....

Edited By John Rudd on 31/01/2017 16:04:22

Will I need to wire the motor back in, I disconnected it in the first test and have not put it back yet. I think this might be a job for tomorrow as Granddaughter has arrived and I am banned from the workshop. Oh well tis another day tomorrow.

Dusty,

I would leave the motor off for now...as long as there are no bare wires, once the switch has been deemed defective or otherwise, then re-connect the motor, fit replacement part(s) and use the lathe.....

Hi John,
The reason I wanted to know if it was an analog meter was because in the past talking people tthough faultfinding they have come back with an answer like "no resistance" When asked to clarify the answer they meant the meter did not move so the resistance was above the range of the meter. (Rather than zero implied by no resistance.) One other thing that can give confusing readings when measuring inductive components is the range switching on auto ranging meters. The fact that the test current has just changed and causes some back EMF in the inductor makes the auto ranging jump back and forth between two ranges giving false readings. If it is a transformer being tested then normally shorting out one of the other windings stops this effect. It is frustrating doing the testing remotely. The tests done so far that have taken days would have only taken minutes if you were doing them yourself.

Edit.  In Dusty's post at 17:12 on the 27th he mentioned clunking noises. I think we should get him to investigate the cause before re connecting the motor.  I think removing the belt from motor then seeing if rotating the motor or the lathe spindle causes the noise.

Les.

Edited By Les Jones 1 on 31/01/2017 17:28:07

Les,

Pm sent....

@ Dusty, although I'm trying to get you to focus on one issue at a time, can you confirm Les's concerns re the noise?

Edited By John Rudd on 31/01/2017 17:38:04