Member postings for Les Jones 1

Yes, One bulb to U1 and U2. The other bulb to V1 and W2.

Les.

I should read posts properly. It looks like the centrifugal switch is faulty. U1 and U2 are the run winding and I asked for them to be disconnected to avoid that winding being connected to the start winding connections via the reversing switch and causing false readings. If it was me I would confirm that if two 100 watt. (40 to 150 watt would do.) were connected one to the wires U1 and U2 and the other to V1 and W2 (With those wires disconnected from the motor.) that they lit up when the start button was pressed as if starting the motor in both directions of the forward reverse switch. That would prove that power would be getting to both windings of the motor. I would do that before trying to dismantle the motor to get at the centrifugal switch. When I misread your locations as near Burtonwood I thought I would probably be close enough to you to look at the problem myself as a last resort.

Les.

The capacitor should still be connected. It is realy the top two terminals that you are shorting out. You could just connect a piece of wire between the terminals so you have your hands free to hold the meter probes. I did not know that chester had a site at burtonwood. I have been to the Warco site a Burtonwood when I was deciding which lathe to buy but it was only a showroom and it was opened up by a none technical person from the office. I have not even seen the Super lux mill let alone taken the motor appart. I don't think Chester would even stock spare capacitors at their Hawarden site.

Edit, I should have worded my instructions more clearly yesterday. I should have said short the top two terminals in the motor connecton box that the capacitor is connected to together.

Les.

Edited By Les Jones 1 on 10/12/2018 18:25:46

Edited By Les Jones 1 on 10/12/2018 18:31:48

Hi Colin,
The OL display means that the resistance that you are trying to measure is higer than the meter can read on the range it is set to. If the reading did not drop to a low value when the capacitor was shorted out then the centrifugal switch or the start winding is open circuit, (It is not likely to be the start winding.) If the capacitor really does only have a capacitane of a few nF then it is faulty. (There are 1000 nF in 1 microfarad.) I find it difficult to believe that both the capacitor and centrifugal switch are faulty.

Les.

When you say that you did not get a reading do you mean that you got an infinite reading ? An infinite (Or at least very high.) reading is what I would expect with the start winding in series wth the capacitor and centrifugal switch. The idea of shorting the capacitor out is so you measure the resistance of the start winding in series with the centrifugal switch, that should be quite low less than 20 ohms. I have no susspicion that there is any problem with your mains supply.

Les.

Just reading though the post again we could be jumping the the conclusion that the motor is faulty. Nothing has been done to verify that the conractor KM1 is being energised. That needs to be checked next time the fault occures.

Les.

If the machine is still in the not working condition do the following WITH THE POWER REMOVED. Disconnect the wires U1 and U2 from the motor terminals. (These are probably the run winding.) Measure the resistance between the teminals they were removed from. If you get a low reading Less than about 15 ohms then this is the run winding. (If you get a low reading go to step 2. If you get a very high or infinite resistance reading then this will be the start winding in series with the capacitor and centrifugal switch. With the meter leads still on the terminals short out the capacitor terminals. If the centrifucal switch is close (Which it should be with the motor stopped.) then the meter should give a low reading. ( Less than about 20 ohms.) If you still have a high reading then the centrifugal switch is faulty. Goto End.
Step 2 Connect the meter leads to V1 and the bottom left hand terminal. (The lable is obscured by wires. I think it will be Z2 or W2) You should get a high reading. Short the capacitor connections. The reading should drop to less than 20 ohms. If it remains high the the centrifugal switch is faulty.

End. Report the results.
One other question. When it failed disd it fail in both forward and reverse ?

Les.

I would think that if the gear on the thread indicator had a multiple of 3 teeth AND the markings on the indicator corresponded to 3 tooth spacing the thread indicator should work. The reasoning is that 4 x 1.5mm = 6mm so that any multiple of 6mm should line up as three teeth move along a 2mm pitch leadscrew is also 6mm.

Les.

I assume it will be made from aluminium. I would try making a broach out of siver steel. Start by machining it down to the size of the shaft that it is to fit on. (Including the flat.) Then turn it down in steps until you have got to the point where there is no flat left. I would try to make each step a little longer than the length of the hole in the prop driver. You may have to make two (or more.) broaches to do it in stages as if the steps are quite long then there will be too much length sticking out of the chuck. Harden and temper the broach.Drill or bore a hole in the prop driver the diameter of the end of the broach. You will then need to find a way to press the broach through the prop driver. An arbor press would probably be best but if your lathe is substantial enough you may be able to use that to press the broach through. A rotary broach would be another method. There was an article in MEW some time ago about making a rotary broach. I think it was by Michael Cox. I think details are also on his website.

Les.

Edited By Les Jones 1 on 08/12/2018 08:44:13

Edited By Les Jones 1 on 08/12/2018 08:45:19

Hi Phil,
A few years ago I made a very basic tool grinder based on a Machine mart cross vice and a cheap 5" grinder (I think from Aldi or Lidl.) There are some pictures in one of my albums called cross vice tool grinder. It might give you some ideas. Note the hub on which the grinding wheel is mounted is keyed onto the shaft so it is safe to run the motor in either direction.

Les.

It looks like it is configured for star connection (415 volts.) Are there three wires from inside the motor connected to the "N" terminal or just one. If there are three wires it should be possible to configure it to delta (240 volts.)

Les.

Are you sure that the motor is not configured for 415 volts (Star.) rather than 240 volts (Delta.) ? Have you configured the inverter for the correct maximum motor current ?

Les.

Just a warning about rotary encoders removed from HP printers, One of my first attempts at putting a DRO on my mill I tried using an encoder from an HP500c printer. If irst did some tests turning it by hand one revolution. I got 500 counts. When fitted I found it was not quite right. It turned out it was 504 counts per revolution. So don't assume it will be a nice round number.

Les.

Hi John (M),
Can you draw a diagram of how the mains wiring is routed showing things like NVR switches and connection blocks. Could you also post a picure of your V16 (I have looked on the web but there seem to be a number of variants.) The random readings suggest that it might be a bad connection arcing but only when a reasonable current was being drawn. (Like when the motor was running or the pamp connected as a load.) This is not something that you would normally expect to cause an RCD to trip as there is no leakage to earth but I have seen it happen with switch contacts not closing and opening cleanly.

Les

Dave,
You must have been lucky that the fans worked as you must not have been checking the polarity when connecting them as you first connected them to an AC supply.

Les.

Hi Martin,
I thought the same thing about the fans that Dave W tried to connect to the electronic transformer as he did not mention anything about adding a bridge rectifier an smoothing capacitor. When I first saw these electronic transformers I thought they were just a switch mode power supply without the output rectifier but when I opened one that I was given I found they did not even have an input reservoir capacitor so the output is a high frequency square wave modulated with the 100 hz waveform of the input bridge rectifier. Warco lathes and mills have the tachometer power supply built onto the same PCB as the mains input filter. This can't be the case with the Chester V16 as the mains filter can be seen next to the electronic transformer.

Les.

If the design is the same as the 20V of Dave W's then look to see if there is another small transformer and rectifier that powers the tachometer board, If so try disconnecting the mains supply to that. The fact that is displaying anything other than zero when the motor is not running is an indication that the fault may be in that area.

Les.

If it is a 4 jaw independent chuck there is no need to centre it precisly on the rotary table.

Les.

I think Martin W is thinking along the right lines. I suggest disconnecting the live and neutral connections to the electronic transformer and see if the problem still occures. I can't read all of the lable on the electronic transformer so I can't tell if it is one designed for low voltage (12V) QA lighting. I assume that the PCB with the Atmel chip on is the tachometer and is probly supplied from the electronic transformer so it will probably stop working at all with the mains removed from the electronic transformer.

Les.

Hi Colin,
I can't follow The wires in the connection box well enough to identify the connections to the centrifugal switch directly. I think I can follow it well enough to see that the capacitor connects to the top two terminals. If you disconnect one of the wires to the capacitor then measure the resistance between these two terminals I would expect you to get a reading of about 10 ohms.(I am guessing it will be about a 0.75 HP motor. It would be lower on a larger motor.) This reading will be the centrifugal switch in series with the main and start windings. If the switch is open circuit the reading will be quite a lot higher. (A high reading could also be caused by one of the windings being open circuit but this would be unlikely,) You could do a very rough test of the capacitor by connecting a 100 watt old fashioned tungston filiment lamp in series with the capacitor, When connected to thje mains via the capacitor the lamp should light almost as bright as if connected directly to the mains. As the reactance of a 150 uF capacitor at 50 hz is about 21 ohms the voltge across the capacitor should be about 8 volts. Only try this if you are confident working with live mains circuits.

Les.