Neil Wyatt | 16/08/2014 17:07:02 |
![]() 19226 forum posts 749 photos 86 articles | There's a typo there - both 2 and 3 can't be right. Neil |
Roger Hart | 16/08/2014 18:10:20 |
157 forum posts 31 photos | So, my apologies, its a capacitor start/induction run motor so my earlier comment was wrong. But the windings do not seem to be on the usual terminals, so going by winding colours (harder to confuse) we have red+black as the running winding so to live and neutral. The starting winding plus switch is blue+yellow and go in series with the capacitor to live and neutral. To reverse direction then change over either red+black or the blue+yellow. You may be tempted by Les' suggestion which I would also follow - but be careful. |
Les Jones 1 | 16/08/2014 18:38:38 |
2292 forum posts 159 photos | Hi Mark and Roger, Les. |
Mark P. | 16/08/2014 19:39:42 |
![]() 634 forum posts 9 photos | Hi Les, my mistake forget statement 3. There are 4 wires going to the windings,Yellow, Red, Black and Blue. I suppose that the Red and Black are the run windings and the Yellow and Blue via the switch are the start windings. Just rechecked the figures, A to AZ 4 ohms, S to T 15 ohms via switch (will clean switch contacts tomorrow) T to A infinite, A to S infinite so I assume that they are not connected internally Mark P. |
Les Jones 1 | 16/08/2014 20:06:58 |
2292 forum posts 159 photos | Hi Mark, Les. |
Mark P. | 16/08/2014 20:16:09 |
![]() 634 forum posts 9 photos | Thanks for your help Les, and everyone else much appreciated. Mark P. |
Mark P. | 16/08/2014 20:52:06 |
![]() 634 forum posts 9 photos | Last question. The capacitor goes in series with the switch ie. Live to one side of the capacitor then to.the switch and then off to the start winding? Mark P. |
Emgee | 16/08/2014 20:59:06 |
2610 forum posts 312 photos | Possibly best live to the switch - switch output -capacitor -start winding. Emgee |
Mark P. | 17/08/2014 13:42:37 |
![]() 634 forum posts 9 photos |
I'm still having trouble getting my head round the connections. The capacitor is connected to terminals Z and S, the red and green wires which means that it would not be connected in the start circuit. As you can see from the photo when things are connected as per negative to Z and A, Live to AZ the capacitor is not connected to the switch. Am I missing something fundamental? I feel that the capacitor should be in series with the switch,not connected across Z and S. Would this account for the yellow flash and the tripping of the RCD? Mark P. |
Vic | 17/08/2014 13:58:04 |
3453 forum posts 23 photos | With only a live, neutral and earth on a single phase cable why would a manufacturer put five or six terminals on a motor? Just asking! |
Nick_G | 17/08/2014 15:16:22 |
![]() 1808 forum posts 744 photos | Posted by Vic on 17/08/2014 13:58:04:
With only a live, neutral and earth on a single phase cable why would a manufacturer put five or six terminals on a motor? Just asking!
So that the single phase motor can be reversed if required. There is a bit more to it than with a 3 phase motor.
Nick |
Keith Long | 17/08/2014 15:20:26 |
883 forum posts 11 photos | Vic Motors are made for universal application - to be as versatile as possible. If the motor has to be able to run in both directions under switch control then the start and run windings need to come to separate terminals so that connections can be made independently. So with run and start windings - that's 4 terminals; if the centrifugal switch is brought out to the terminal plate that will be 2 more and you might find a terminal post to anchor the earth to as well. |
john fletcher 1 | 17/08/2014 16:40:38 |
893 forum posts | The start winding will have the highest resistance, much higher than the run winding which should be around 4 ohms. As some one has already stated, the start winding, the capacitor, together with the centrifugal switch form a series winding, which are then connected in parallel with run winding. Once the motor is up and running the centrifugal switch opens, leaving just the run winding connected to the mains electricity. If the capacitor is connected to terminals Z & S Ok, As I see from your picture(photo) one side of the centrifugal switch is also connected to terminal S OK there. So, from terminal S to the lower Lucar connection on the Bakelite centrifugal switch board, through the switch, checking that the contacts are clean and that they do close up, then to the upper Lucar connection, that forms the start circuit. At this stage you should, using a multi meter on the ohms range, be able to measure the start winding circuit resistance. Its not easy to test the capacitor as they are special AC electrolytic, not the ordinary paper type although they will be OK. It would appear that you need two short links one between Z & AZ, the other between A & T. The mains is connected to A & AZ either way round. To reverse the motor move T to AZ and Z to A. The most important wire is the EARTH. SO ENSURE YOU HAVE A GOOD CLEAN EARTH CONNECTION, and if your motor is mounted on resilient rubber mounts check there is a link between the base mounting plate and the motor the motor casing. Let me know how you get on.Ted |
CotswoldsPhil | 17/08/2014 17:46:44 |
![]() 196 forum posts 112 photos | Hi Mark P, I have today just swapped stators between two Crompton and Parkinson motors, one of which has an intermittent connection - it kicks when shocked, the other had worn bearings so making 1 good one out of two. I'm looking at the wiring label inside the motor terminal box - Z - Blue (or Yellow depending on rotation) motor wire + Green/Red from capacitor AZ - Red + Maroon + Yellow (or Blue depending on rotation) motor wires A - Black motor wire + Green/Red capacitor - This is the Neutral Connection T - Maroon motor wire - This is the Live Connection Don't forget the earth tucked in the corner of the connection box on the end case. To change the direction of rotation - swap the Yellow and Blue wires on Z and AZ My motors, are both working (one a lot faulty) each one in opposite directions, with the wiring shown above. I did have some difficulty confirming which was the blue wire (on AZ) because the colour has faded somewhat in the 40 odd years since manufacturer. In the end, I decided that the third wire was quite different from the Red and Maroon connected to the AZ terminal and must be the blue one. Hope this might help Regards Phil H
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CotswoldsPhil | 17/08/2014 19:00:55 |
![]() 196 forum posts 112 photos | Hi Again, Just reviewed the post and need to add that the Maroon wires are in fact for a thermal cutout fitted to the motors I am working on - so this may be the link that is being talked about. Regards Phil H |
Mark P. | 17/08/2014 19:31:58 |
![]() 634 forum posts 9 photos | Thanks chaps, I think I can see what is going on. On a different tack anyone know anything about an Evershed and Vignoles 250V Megga? Mark P. |
Les Jones 1 | 17/08/2014 19:52:42 |
2292 forum posts 159 photos | Hi Mark and others, Les. |
CotswoldsPhil | 17/08/2014 20:04:37 |
![]() 196 forum posts 112 photos | Hi Mark and others, I've worked up a hand-drawn schematic for the motors I've been working on, it's in my albums and reproduced here. The maroon wires are connecting a resettable overload cut-out on my motors. The centrifugal switch may be on the other side of the capacitor, it's also closed when stopped. Black and Red are run winding Yellow and Blue start winding. AZ is the common terminal. Hopefully it illuminates your problem. It's a bit manic spider but ..... Regards Phil H
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