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Thanks for that. As two of my terminals are marked with a double title, i.e Z2W2 and Z1W1, is that of any particular significance to this particular motor or could they be called anything or is there an industry standard for marking these connections?
Sorry Pete, not being an electrician I do not know the answer to your question. The general census is that the lathe was originally a 3 phase but it has been rewired to be used on single phase. Whether the motor is a 3 phase motor or single phase I do not know at this time. I just would like to know if it is in working order. What sort of readings would I get if that motor was all Ok?
Take the resistance readings of two V, U, Z, W. will be a good place to start. Like I said earlier the Z pair will most likely be your start winding and the U pair will be your run winding. Have a look at this old thread might jog your memory http://www.mig-welding.co.uk/forum/showthread.php?t=36412
Opps bit late coming in there sorry.
Opps bit late coming in there sorry.
rtbcomp
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The capacitors should be open circuit and will give infinite resistance when measured with a DC meter.
So then that means the motor is OK then? Is it a 3 phase modified to run single or a single phase original. I will check the continuity of all connections to motors body to check for faults next as the last time I had a motor problem it turned out to be totally knackered. See the link on eils' last post above.
Thanks for that. If I end up having to get a new motor what speed should I get,1400 or 2800 rpm. The old motor has a double pulley on it which I suppose gives you the choice, but what do I know!! From what I can glean from the internet the horse power is 1.5 hp but the specification list does not state what the power supply is. It states buyers choice! So my question here is is 1.5hp a three phase one and if so will I need a larger one for single phase?
Another point on lathes is does the chucks on different Lathes all rotate in the same direction? I have another lathe and its chuck rotates looking from the back of the chuck in a clockwise direction. Anticlockwise from the bed area where you would be working. I just want to make sure that if I do change the motor I get it going in the right direction!
Another point on lathes is does the chucks on different Lathes all rotate in the same direction? I have another lathe and its chuck rotates looking from the back of the chuck in a clockwise direction. Anticlockwise from the bed area where you would be working. I just want to make sure that if I do change the motor I get it going in the right direction!
Is this your lathe http://wentztech.com/WebDisk/Metalworking/CZ300/CZ300A Lathe Manual.pdf
eil:--Your link is not working!
I have checked continuity between the wiring block and the motors body and there are no indications registered on the Avo set at continuity. But I decided to take off the front end cover just to do a visual on the wiring to try to trace which of the wires went where and to see if there were any signs of shorts or overheating/burning. I had to use a 3 legged puller to get both the pulley off and the cover. Just as well I did as it meant that the cover came off slowly and I could see when it was halfway off that one of the two wires attached to the cover had come adrift from its soldered joint. If I had just levered it off with a couple of screwdrivers, thinking it was just a cover and had nothing mounted on it, I probably would have blamed myself for damaging it!I will take a couple of photos' when I can get to the garage as its raining cats & dogs & blowing a gale at the moment!
Cheers,
I have checked continuity between the wiring block and the motors body and there are no indications registered on the Avo set at continuity. But I decided to take off the front end cover just to do a visual on the wiring to try to trace which of the wires went where and to see if there were any signs of shorts or overheating/burning. I had to use a 3 legged puller to get both the pulley off and the cover. Just as well I did as it meant that the cover came off slowly and I could see when it was halfway off that one of the two wires attached to the cover had come adrift from its soldered joint. If I had just levered it off with a couple of screwdrivers, thinking it was just a cover and had nothing mounted on it, I probably would have blamed myself for damaging it!I will take a couple of photos' when I can get to the garage as its raining cats & dogs & blowing a gale at the moment!
Cheers,
More wire tracing on motor shows that the lower Capacitor is 150-200uf 275AC unit and its terminals are connected to V2 & Z2W2. There is then a wire from V2 to one of the terminals on the end cap speed switch. The upper Capacitor is a 20uf with UN 400vac & UN450vac marked on it. Its' terminals go to Z2W2 and Z1W1. The broken wire from the end cap(now re-soldered)is connected to Z2W2. One photo shows the reverse of the motors wire connection block. 10 wires in all. So there is two to each Cap, two to the speed switch and 2 black and 2 red wires which are the field windings and they are as per readings previously found when checking resistance. i.e. 70 & 93ohm. All I need to do is refit it and see if the lathe works!
As it stands now the wiring`s not right, I would start again.
The centrifugal switch or speed switch as you call it connect its two wires to V1 and V2.
The start cap 150-200uf connect to V2 and Z1.
The run cap 20uf connect to V1 and Z1.
The lathe has a forward and reverse switch on it, the four wires that connected to the motor should be two live wires and two neutrals you will need to confirm this with your voltmeter.
If you want to test it on the bench you will have to put in a couple of links to connect the run windings, link U1 to V1 and U2 to Z2.
Copy this diagram
The centrifugal switch or speed switch as you call it connect its two wires to V1 and V2.
The start cap 150-200uf connect to V2 and Z1.
The run cap 20uf connect to V1 and Z1.
The lathe has a forward and reverse switch on it, the four wires that connected to the motor should be two live wires and two neutrals you will need to confirm this with your voltmeter.
If you want to test it on the bench you will have to put in a couple of links to connect the run windings, link U1 to V1 and U2 to Z2.
Copy this diagram
Yes quite right, indicated by the arrow on the top left. but fitted to the lathe the forward/reverse switch will do away with the links.
