Capacitors for HIGGS motor.

[Guineafowl]

If the half-rivet is related to the problem, it would only be in relation to the centrifugal switch, and thus the Start circuit.
The test that I suggested in Post #74 eliminates all that.

Thank you for the resistance values. They look reasonable.

Yes, other than something intermittent, like a loose connection, I can’t see anything wrong, nor any reason for the behaviour.

Ideally, you’d megger it and check the caps, but if not, button it all back up and try it again.

 

[HSGB]

I have noticed that the switch contacts are shut:

Then, if I rotate the rotor shaft 180 degrees, they open:

The collar that slides up and down the shaft is not sliding parallel to the shaft it's sort of ten degrees out, this is causing the contacts to open.

If this is happening during start up then, I reckon it would cause a problem. Has this rivet got something to do with keeping that sliding collar true to the shaft? I am going to de-solder it, remove the new bearing and check this switch again.

Check for any continuity to earth, while you’re in there.

Yes, all seemed fine.

 

[Martin-Sy]

Then, if I rotate the rotor shaft 180 degrees, they open:

That should not happen.
Just to be absolutely clear about this.....single phase induction motors cannot self start without being given a 'kick' in whichever direction you want it to run.
That's what the start winding and capacitors are for. As soon as the motor is up to speed the centrifugal switch should open and disconnect the start winding.
The switch will only close again when the motor slows down.

 

[HSGB]

Took it apart again, still cannot see anything wrong. I still don't know where that stupid piece of rivet originated from. Don't really know where to go from here. There seems to be nothing to rectify. The only thing I can notice is that the sliding collar tilts on the rotor shaft when in certain positions, thus causing the contact to open. I cannot see a way of fixing that.

 

[Seadog]

Is there excessive wear in the shaft and/or the plastic sleeve?. Do both bobwrights move smoothly?

 

[HSGB]

No, there seems to be no wear on the sleeve. The sleeve rotates with the shaft. I don't think the sleeve actually touches the shaft though. No, the shaft is in in fine condition. The roller bearing is a very snug fit. Yes, the weights move freely and are under good tension from the springs which don't seem to have fatigued at all, over the years. In fact, everything looks in very good condition.

 

[dobbslc]

Have good look at the windings incase you damaged any when you were trying to remove the end cap right at the start of all this.
I did exactly that on a drill motor and wrecked it.

 

[Seadog]

The bobweight assembly must rotate with the shaft. I'm struggling to picture how this operates.

 

[Martin-Sy]

It looks like the plastic collar rubs against the part pointed to in the picture. It looks worn unevenly.
Could this be the issue?

 

[Seadog]

Which is why I'd expect the sleeve to be a running, or more likely, an interference fit on the shaft. The contact plate, obviously needs to remain fixed to the motor body, the bobweight assembly needs to rotate with the shaft.

 

[Martin-Sy]

Which is why I'd expect the sleeve to be a running, or more likely, an interference fit on the shaft. The contact plate, obviously needs to remain fixed to the motor body, the bobweight assembly needs to rotate with the shaft.

I think the collar slides along the shaft when the bob-weights fly out. I agree tho it should be a good running fit.

 

[carbon]

I don't see many motors with a switch inside but to me I would have thought there should be a bushing on the motor shaft to prevent the sliding section moving at an angle at slow speeds.

 

[Seadog]

The sleeve bears on the bends of the sprung contact, not the pip, in my opinion, which should prevent canting.

 

[HSGB]

Have good look at the windings incase you damaged any when you were trying to remove the end cap right at the start of all this.
I did exactly that on a drill motor and wrecked it.

I checked all them yesterday, they seem fine.

The bobweight assembly must rotate with the shaft. I'm struggling to picture how this operates.

The weights do rotate with the shaft, they are held on to a mounting by two bolts, as in the first photo of post 92.

It looks like the plastic collar rubs against the part pointed to in the picture. It looks worn unevenly.
Could this be the issue?

I saw that and could not figure it out as the collar only touches on the other side. If you were to try and centralise it you would misalign the actual switch contacts. I have been wondering though, whether the spring steel part of the actual contacts should have a more pronounced hump in it to stop the collar going lop-sided.

I think the collar slides along the shaft when the bob-weights fly out. I agree tho it should be a good running fit.

Well, there was nothing there when I first took it apart. Surely if it was actually touching the shaft a 2800 r.p.m. Tho collar would be worn out in no time?

 

[HSGB]

he sleeve bears on the bends of the sprung contact, not the pip, in my opinion, which should prevent canting.

Yes, you have seen what I have thought, as well. Do I bend a bit more of a hump in it?

 

[Seadog]

Well, there was nothing there when I first took it apart. Surely if it was actually touching the shaft a 2800 r.p.m. Tho collar would be worn out in no time?

It wouldn't since it's rotating with the shaft. It just needs to slide open and closed.

 

[HSGB]

It wouldn't since it's rotating with the shaft. It just needs to slide open and closed.

Of coure! I'm getting all confused now.

Anyway. there was nothing there and I have never had it apart before and I don't reckon anyone has since leaving the factory.

As mentioned above, I reckon this spring steel need a larger hump in it. I am wondering if I flattened it a touch whilst getting the bearing off. I reckon two larger ramps for the collar to ride on when at 90 degrees to the actual springs will help it run true. I have already done it a touch and it does seem to make a difference, it doesn't seem to be opening and closing now, like a set of points.

It looks like the plastic collar rubs against the part pointed to in the picture. It looks worn unevenly.
Could this be the issue?

Martin, the collar only seems to touch the inner half of that contact, see here:

That's a bit exxaggerated because I'm holding it. This photo clearly shows the shinier area where the collar has been contacting over the years:

I am going to reassemble it and see what happens, now I have pronounced the ramps in the round spring. I reckon that should act as a stabiliser sort of affair and at the moment it isn't, as it's too flat.

 

[Argonman]

Very intriguing thread. I’m waiting with bated breath. Any progress?

Chris