Warco. WM280V-F

whilst adjusting the position of my chuck guard ( to clear the toolpost ) I inadvertently broke the micro switch which cuts the drive when the guard is raised.

Despite my Lathe being set only 4” from the wall , I managed to remove the rear headstock plate and retrieve the micro switch , following which , I repaired it and replaced it .

With all refitted, the Lathe would not run , called Warco who advised that the micro switch old still be faulty , try connecting its two wires together . This I did but it still will not run .

Using a mirror, and some agility I was not aware I possessed, I have determined that all wires seem to be firmly connected, but I noticed that the Contactor has a button which protrudes. Not being an electrician, but assuming that this button should be depressed , I tried depressing it and pressing the start button on the Lathe . This resulted in the Lathe starting up .

So, my request is , can someone tell me the definitive answer , should that black button on the contactor permanently be depressed under normal conditions , or is something not happening which normally causes it to engage , if so what ? .

Please explain in simple understandable terms due to my Blackcountry , Thick as Wood , persona , ta !

D.A.G,

I sounds very much like a reset button to me. You could test it out by operating the guard to stop the motor again and then see if the button needs pressing to get it started once more.

I wouldn't expect it would need that sort of operation with normal ON-OFF working of the lathe

Regards

Brian

I suspect the button that you are referring to just pushes the contacts closed manually. A picture of the contactor showing the location of this button would help.  The interlock switches will all be contacts that are closed when the guard / covers ar all in position. All of these switches will be in series together with the stop button and in series the supply to the coil on the contactor. Check that all the covers are in position and that the emergency stop button is not latched in is fitted. I you have a wiring scematic in the manual then post it so we know how it is wired.

Les.

Edited By Les Jones 1 on 12/12/2017 17:18:10

Hi D.A.G

I'd bet money that Warco are right and the micro-switch is still broken, or iit sn't being worked by the cam of the end of the chuck guard mount.

The button on the contactor works the contacts manually to test it. It's not useful other than to confirm that your problem is the contactor not getting control power. It's the circuit that powers the contactor's electromagnet that's broken, the chuck guard micro-switch being chief suspect. However, it's also necessary to have the motor set to run Forward or Reverse (not the 0 position) and for the cover over the drive belts and gear banjo to be in place. Double check!

With the lathe disconnected from the mains, it's possible to get at the micro-switch wires from the front.

• Undo and gently lift up the panel with the ON/OFF and Forward/Reverse switch on it. (You can't move it far because of the attached wiring.)
• The chuck micro-switch's cable entry can be seen on the right just under the edge. It has two wires leading into it.
• You can by-pass the switch by cutting the wires and connecting them together, leaving the switch with two unused wires coming from it.

Is that what you've done and it still doesn't work? Can you post a photo?

Dave

That 'button' on the switch is normally a press to operate (or release, to disengage the contacts). Simple as that. Normally a cam or lever presses against that button to close the contacts (of a normally 'open' device).

Micro switches come in basically two versions - normaly closed or normally open contacts; yours is a normally open version, so that button needs to be depressed to make the elecrical contact which will allow you to start (and run) the machine.

These devices are not meant to be accessible for that button to be used as a test button. They are concealed, covered, or whatever, and operate remotely (by you closing the guard properly, in this example) as a safety feature. They can be removed/bypassed from the circuit at the operator's risk, as suggested for testing purposes.

Hope this makes things clearer - ie when the guard is properly located, something on the guard shaft should be closing those contacts (pressing on that button sufficiently to hold the contacts closed). If the contacts are not closed sufficiently, the machine will either not start or may stop during operation if contact is lost, even momentarily.

Editedvto add that there is often a longer lever over that button which willdepress the button from a distance remote to the actual microswitch location  Google images of microswitches and things may become clear as to how your particular switch is operated.

Edited By not done it yet on 12/12/2017 18:41:40

As an aside, TWICE (how's that for stupidity?) I got caught when my lathe would not run. Each time, after an afternoon checking circuits and voltages, found that I had leaned on the Emergency Stop button and latched it down!

My Chuck Guard microswitch (and those for the gear and belt covers) are wired into the 24 volt circuit that feeds the worklight, and controls the feed to motor through a relay. (My lathe has a VFD and a 240 volt three phase motor)

Presumably, no blown fuses?, (worklight functioning? if fed through the Lathe's control box)

Howard

Thank you all for taking time to consider and respond to my problem .

The Contactor is as per this photo,

The wiring diagram is as below.

Thank you for suggesting that I check the emergency stop button and belt/gear cover . Having been caught by that in the early days of ownership , I had gone through that process , but I appreciate your concern .

Taking up SOD’s suggestion of removing the top front plate to access the guard limit micro switch , I discovered ( not

visible using mirror at rear ) that there is a wire which is not connected . I think that it may be a clue as to why my machine won’t run . My god , there’s no flies on us in this part of the world ! .

Above is a picture of the loose wire , the blue one with red tag , Not the faintest where it goes ! And I can’t see from diagram below any suggestion of the terminal block .

Apologies for the quality and orientation of the photos, getting my phone into the space behind the Lathe and getting a meaningful shot was not easy .

DAG

The floating blue wire appears to be a connection to mains neutral. According to the circuit diagram there should be a mains neutral connection to terminal A2 of the contractor. Without this the contractor will not operate. I suggest you check to see if the connection to A2 is missing.

hth

I found it impossible to get a meaningful photo of the wiring - there's always something in the way and/or the important bit is in shadow.

Anyway, on my machine:

• The blue neutral wire that's grouped into a cable-tied bundle goes to the ON/OFF switch
• The other, which appears to have become detached on DAG's lathe goes to the contactor. As Mike says this is A2 on the diagram.

I can't see the marking on my contactor to confirm but the blue neutral goes to the bottom right terminal, arrowed on the diagram. This is the contactor as seen from the rear panel.

This would be an easy fix if it wasn't awkward to reach. You have to approach the contactor from the rear and I'm afraid you will have to move the lathe to get access. May be worth experimenting with a mirror but...

I'd use a long screw-driver to slacken the terminal screw being careful not to let it fall out. Then I'd use long-nosed pliers to feed the wire into the entry hole under the terminal and re-tighten the screw. If you don't have suitable pliers make a rod with a releasable loop on the end to steer the wire into position.

While you're inside, it's worth gently tightening all the terminals to make sure they're all firm. The wire probably got displaced during your repair but I suspect the terminal wasn't quite tight enough in the first place.

Dave

Just a word of caution. The terminal indicated in Dave’s sketch seems to be clearly labelled A1 in DAG’s photo. From experience with similar components I would expect A2 to be on the other end of the contractor.

Yes indeed! I've double checked with a torch and - phew - my home-made diagram matches the Siemens contactor in my WM280VF. (I feared one of my famous mistooks had been made.) It's not easy to see on the actual contactor but the terminal I arrowed is marked A2. Possible that other contactors locate the terminals differently.

Dave

I wonder if the terminal blocks are the squares with black dots that the incoming L&N connect into, there are 4 blue neutral wires into that symbol and also 4 into the choc block. If that is the case then you should be able to trace the 3 blues coming from the choc block to either Inverter, contactor or fan.

Managed ( without lifting ) to spin the machine through 90degs , and am now able to access the electrics box .

Again thanks to all for your Input , SOD , my workshop is so tight , me and a long handled screwdriver won’t fit at the same time hence spinning the Lathe .

Above new photo of Contactor and below shot of underside

This is upside down ,that said , is that blue wire the one you suspect is missing SOD ? .

I have put a mutimeter over the micro switch and proved that it is making and breaking as it is supposed to.

I shall certainly check that all wires are firmly fixed whilst I have the back open .

I would have expected terminal A2 to be at a lower level than the blue wire shown in your photo. Like terminal A1 shown the previous photo. If we’re right about it being where the floating blue wire should go it will have nothing currently connected to it

Hi DAG,

Mike's got in first and he's right again. A2 is two steps down and further back. The blue wire in your photo is correct, but it isn't the same as your loose wire.

In your photo, here turned the right way up, I've ringed A2's terminal screw in red. You can't see where the loose blue wire goes up and under behind because the bundle of wires is in the way.

The contactor terminals are in steps. You want the bottom right terminal which is at the back.

Hope that make sense!

Dave

Edited By SillyOldDuffer on 13/12/2017 20:51:19

Edited By SillyOldDuffer on 13/12/2017 20:53:39

Hi SOD (Dave)

Your clearly a wizard of some sort , turning my photo the right way up , magic ! , and since the blue wire was discovered on the base of the box between the inverter and the Contactor , I have every confidence in your analysis being spot on too .

Tomorrow, given time , and managements permision following completion of domestic duties , I shall have a good look at the bottom of the Contactor and try to find the fixing location for the loose wire .

Thank you all who have responded , much appreciated .

Just a quick update ,

Dave and Mike , thanks , you were both quite right in that the wire should be fastened in to A2 .

It was so easy with the rear of the machine accessible, I released the Contactor from its mounting and was able to replace the wire into A2 and fix it good , taking the opportunity to ensure all others were solid also . The Contactor was then replaced , all other bits fitted back , and Hey presto ! I have a working Lathe , ( bliss ) .

It is such a relief that all is well , and also that there are so many knowledgeable members on the forum who are happy to resolve someone’s problems , thank you all .

Mike and I may have helped but you had all the hassle and the heavy lifting - literally. Well done you!

Glad it's working again.

Cheers

Dave

Edited By SillyOldDuffer on 14/12/2017 21:32:59

We all try to help, against the day when the boot is on the other foot, and we have a problem

That's what The Forum is all about.

Howard

Sorry ; it’s me again !

It came to pass , today , that I wanted to do a bit of screw cutting , So , after much faffing about with the gear train to give me the desired TPI , I was ready to make swarf .

As I switched the power on at the socket , I noticed the speed display light up , and then go blank , as in No light .

The fan is working , I can hear that , and if I try to start the machine , I hear the contacts pulling in , but no action by way of spindle movement .

Has anyone experienced such a problem ? And does anyone have a clue as to what the fault might be .

Since it is late Saturday afternoon , I have not been able to obtain any assistance from Warco as yet , but I have every confidence in the forum members .

David .