Warco. WM280V-F

Measure the voltage between the L and N terminals (AC voltage.) on the filter board. This is also the power supply for the tachometer. I suspect a wire has come loose between the mains input terminals and the mains input to the VFD this then goes on to power the filter board. See the schematic you posted 09:11 on 13/12/17

Les.

As you have been playing under the "hood" with the change wheels it may be worth checking that the safety micro-switch on the cover has clicked when you screw the cover back on?

John

Les : thanks , how do I identify the filter board , can you direct me in relation to the Contactor ( which caused my last problem and which I now recognise) and the VFD unit , which even with my very limited ability , is recognisable? .

John ; the micro switch bayonet on the change wheel cover was loose when the incident occurred , and it was after replacing the cover that the speed display light panel died . I can understand the logic of the motor not working if the cover was not properly positioned, but I don’t understand why it would cause the speed display to loose power ?

Thank you both in the meantime, for taking interest .

Regards, David .

I have never seen inside a WM280V lathe so I have no idea where it is physicaly situated.  This is a picture of the board from some previous thread.

This is the reasoning for my suspicion as to where the fault is located. According to the schematic the mains cable comes into a connector block and there are three pairs of wires from there. One to the fan. (Which you say is working.) One to the switches and contactor. As you say that the contactor clicks when you press the start button then this wiring must be intact.. The third pair goes first to the terminals R/L1 and S/L2 on the VFD an then another pair of wires go onto the filter board. As I have seen pictures of the filter board I know it is easy to get to the L and N terminals to see of power is getting there. If power is getting there then it also must be getting to the VFD. As I have never seen the VFD in your lathe I don't know how easy it is to get to terminals R/L1 and S/L2. A wire must have become disconnected at either of these terminals or at the terminals that the incoming mains cable connects to.
It is the L and N in connections on the left of the picture of the filter board that you will be testing If you can get the the connections on the VFD more easily then do the voltage check there first.

Les.

Edited By Les Jones 1 on 04/02/2018 09:06:53

Les ; again thank you .

Rather than unbolt the machine and swing it away from the wall , I removed the front plate ( on which the speed indicator is mounted ) and found just behind it the filter board , what luck, thought I .

Not being versed in the arts of the electrician, I could see the terminals you spoke of , but they appeared well protected with no opportunity to touch my meter too, there were also out terminals with similar markings . That aside , I carefully rested the front plate securely, and replaced the plug into the mains socket , I then switched on and to my surprise, the display light up ? . Why I have no idea , but I accepted this stroke of good fortune and replaced all to its normal state .

I have since been starting and stopping the machine quite normally whilst cutting the thread that I started out on .

Les , I must thank you , and all who contribute when the likes of me have a problem , if you don’t fix the issue , you at the very least give us the confidence to have a look and even a go at doing stuff we would probably shirk away from otherwise . Thank you .

All appears well with the Lathe now .

I think the REAL fault is on the connections on the VFD. Probably moving the filter board has disturbed the connections on the VFD. You need to fix it properly rather than leaving the intermittent connection in that state.

Les.

Just spotted you have a new problem David. I agree with Les, the symptoms sound like a a loose connection, quite likely caused by your recent rummagings inside.

With luck me taking a few photos in anticipation of another visit from the gremlins will keep them happy and you'll never have another problem! However, what you may be looking for next is behind the back panel.

First, top view of the VFD and the power input connections. Might be one of these loose.

Note that the VFD is switched on, there is no error code displayed, and the (blurry small) red STOP light is on, meaning the VFD is ready to go but the motor hasn't been activated. This is normal.

Second, on the lower front edge of the VFD is a flip up cover guarding the control and motor connections. The red-ended control wires connect to the small green terminal block . The larger terminal block underneath is the motor connections.

One of my red-ended wires looks suspiciously loose. If so I just did it by rummaging around...

Dave

Edited By SillyOldDuffer on 04/02/2018 17:43:21

Thanks Dave for posting those two pictures of the VFD. at least it looks like it is easy to get to for D.A.G to check the connections.

PS. I have copied them for future reference.

Les.

Les ; you are right I shall have to bite the bullet and crank the Lathe round so that I can get to the rear properly and fix it , thanks .

Dave ; thank you also for taking time out to send photos of the specific bits that I need to examine , most helpful! , as per above , will do

Regards both ,

David

D.A.G,
Have you checked the connections yet that we suspect are causing the intermittant problem. I think it would be helpfull to others with that model of lathe particularly if you posted a photograph of the place where tha bad connection was located.

Les.

Les ; I am afraid I have to own up to an indulgence of laziness! , the Lathe has been performing well and the thought of undoing the 6 clamping bolts and swinging it round through 90 degrees was too much ,However , now you have highlighted my sloth, and since I am spared certain domestic chores this week , I will get the job done .

In fairness , it is remiss of me to ask for , and receive assistance , and then not respond in a way which may help others , thanks for the prompt .

David .

My good deed for the day; the Album WM280VF Electrics is a collection of photos showing the physical layout of my 280, inside and out. I hope it will help experts like Les to steer anyone with a problem in the right direction. Quite likely to be me one day!

I can't claim much credit for this. It happens that I have particularly easy access to my headstock plus an interest in electrics and digital photography. If that helps anyone else, hurrah.

Dave

Dave ; well done with the album, I am sure it will be useful going forward! .

Les ; Today I turned the Lathe through 90 degrees so that I could access the rear panel, during a check on the wire connections I discovered that ( see photo of connector block 13/12/17 ) one of the two brown wires , which were joined in a white jointer , had come adrift ,though was still within the sheath. Despite it being loose, it must still have been making contact , hence the machine working ? .

Not having connectors of that type , I removed it , soldered the two wires together , and replaced them in the connector block .

I haven’t yet had time to swing the Lathe back , (note to myself , I must try it running before I do that ) but I am confident it will be ok , thanks again .

David

Hi David,
It's nice to know that you found the fault. It fits the original fault symptoms perfectly. I have never see that type of crimp connector with a palce to crimp two wires. The soldered connection will probably be more reliable than the crimps.

Les.