Member postings for Les Jones 1

It looks like that only 2 connections are used on the terminal strip so live and neutral will connect to them. It looks like there is no way to reverse it. If I was connecting it up I would first remove the two screws that hold the terminal strip to the motor to see if there are any wires connected to the underside of the terminal strip.

Les.

Just swapping over live and neutral in the motor should make no difference BUT there are probably more than two terminals (Plus earth.) in the connection box on the motor. IT DOES MATTER WHICH TWO TERMINALS THAT THEY ARE CONNECTED TO. Post a picture of the connection box and any information that may be inside the lid of the connection box if you are not sure which two terminals to connect to.

Les.

Try monitoring the voltage from the power supply. I suspect the power supply may be shutting down with the increased load when the speed controller is turned up. You could also try connecting the motor directly to the 12 volt supply.

Les.

Hi William,
I don't think that is really suitable for your purpose. It will be designed to control the speed of a motor designed for around 180 to 220 volts. It will provide no isolation from the mains. It will probably use phase control so when it is set to a low speed (Low AVERAGE voltage.) the output will be short pulses of a much higher peak value than the average output voltage. I am assuming that your saw is designed for an 18 volts battery.

Les.

Hi Michael,
Thanks for pointing out the information I missed in the first post. One point about using PC power supplies is that some of them require some load to be put on the +5 volt output before the rated current can be drawn from the +12 volt output..

Les.

You will need to know how much current the motor takes so you can obtain a power supply capable of driving it.

Les.

I had not heard of 4QD so I had a look at their website. They make more than one controller so telling us which one it is and details of what you don't understand would increase the chances of having your problem solved.

Les.

I would try using the type of tile cutter that uses a diamond cutting disk that is kept wet in a tray of water. It will be quite slow but I think it would be more reliable than the scoring methods.

Les.

On the assumption that it is a single phase motor one possibility is that the centrifugal switch is not opening when the motor is up to speed. Before doing anything to the machine wait to see what Warco say about about the motor temperature.

Les.

I second Johnboy25's comment to do exactly what Joe has advised. Do not use the machine until this problem is resolved.

Vasantha Abey's comments are total nonsense

Les.

Edited By Les Jones 1 on 25/08/2019 09:32:14

I agree with the others that they are probably 3BA. This is one source on ebay. but there is than one match searching for "3BA screws.

Les.

I think those motors are WW2 vintage motor/generators. I think if you remove the perforated metal cover on the right hand end you will find there is a commutator that end that originally was the high voltage output. I can't see any brush housings that end so they have probably been removed as they are not required when just used as a motor. Another thing that might have made you think they are faulty is they are probably shunt wound (Rather than permanent magnet.) so they would need a supply to the field winding as well as to the brushes at the left hand end. I think the small motor at the bottom of your last picture is a compressor as you can see a cylinder and cylinder head on the left hand end of it.

Les.

Edited By Les Jones 1 on 19/08/2019 22:08:37

From your description of the external magnetic field from the motor it is a permanent magnet motor. These are DC motors. DO NOT connect it to an AC supply as doing so is likely to demagnetise the permanent magnet and burn out the winding.

Les.

Cut a helix on the mill using the rotary table and a right angle drill attachment. The right angle drill attachment was a lazy way to get a right angle drive.

Les.

I had not realised that you had taken the motor apart and found that one end of each of the two windings was jointed where the transition was made between the enamelled wire and the flexible wire. I assume the picture in this mornings post is with the thermal cut out disabled. I have not seen this type of motor with an internal thermal overload. They normally rely on thermal overload current sensors on the main contactor.

Les.

Gary,
In the picture in your post of Aug 11 08:34 there also seems to be a light brown wire from inside the motor connected to terminal "T" (Top right terminal.). If that is the case then I think this light brown wire is one end of the start winding and the yellow wire is the other end of the start winding. In your first post it also looks like there is also a thick brown wire going off to the right of terminal "T". Can you confirm if this is the case ? Also is there a start capacitor either on the side of the motor or inside the control box ?

Les.

Don't you have any friends with a megger that could check the insulation between the windings and case for you ?

Les.

Are you sure that the socket for the tail light and the stop light are the same ? Some car bulbs are single centre contact. On these the connections are the single centre contact and the outer metal. The other type are small bayonet type and they have two have two contacts. The outer metal is not used as a connection on that type. There also combined stop and tail lights that use two contacts and the metal casing but you do not seem to have any of that type.

Les.

There is a design that uses and android tablet which sound like what you want to do using a PC. I think the same basic idea could be used on a PC if you want to write the software. It was done many years ago with the "Yadro" DRO. This used a PC running DOS rather than Windows or linux. This is a link to the DRO running on an Android tablet.

Les.

Did you get 24 volts AC on the secondary of the 24 volt control transformer and the coil of KM1 ?
I still cannot read the terminal labels on the contactors and circuit breakers or the markers on the ends of the cables.
If your camera has a macro mode you could photograph the individual contactors and circuit breakers. You could also use manual focus instead of auto focus.

Les.