Van Norman 12

[markba633csi]

OK well that's a simple fix- keep us posted

 

[Scra99tch]

So the motor has been running but its a bear to get it going. So I went back to square one and went through all nine leads. To my surprise what I am seeing is that the motor plate looks off like it had been rewound at some point. Who knows I could be dead wrong.

So I went through and measure continuity through These 4 groups of coils.

1-4
2-5
3-6
7-8-9

The Motor plate says for low voltage
4-5-6
1-7
2-8
3-9

Is this not a WYE wound motor?

I am a bit confused.

The coils are all open to each other, I.e. 1-4 does not see the other three vice versa, and all leads do not make contact with the frame.

So here is the results of wiring it in both configurations the original plate WYE. When I power it on it takes forever to get up to speed and eventually just trips the heaters. Until several attempts it slowly gets going to full speed then the motor starts to cool. (Heat thinning the grease out??). It will run like this for several minutes, I have not run it longer though.

When wired to the new configuration where 7-8-9 which meters out to .002 ish Mohm (I have to double check that) the motor does not move. Even after switching at least two of the incoming lines.

Any thoughts or checks I am missing besides a Meg test?

Thanks

 

[Chipper5783]

How much current are you getting on each leg? What rpm does it settle out at?

 

[Scra99tch]

How much current are you getting on each leg? What rpm does it settle out at?

It looks like when wired per wiring plate and when motors moves all three lines in are drawing 4-5-6, are .42A or so.

When wired to the 7-8-9 wye and motor not moving all lines in are about .52A.

Keep in mind when I tested all leads

1-4
2-5
3-6
7-8-9

Those leads all read about the same on ohm meter.

 

[markba633csi]

Did you try separating/disconnecting 4,5, and 6? The motor should run with no load without tripping anything. It will only have half the horsepower since only half the windings are in use. If so then that means you must have a phasing problem with the second winding set
If you are certain about the wire numbers then this may not apply; there may be some other fault, but both winding "stars" have to be in phase
with each other

 

[OTmachine]

Seems to me that we had a motor that was rewound so it was only 440V. Something that was done because all we had was 440 and it was cheaper / easier. Thought that you were getting a new / different motor? I will look to see what I had found to verify coils locations after Christmas.

 

[Scra99tch]

Here a short video.

I confirmed T1, T2, and T3 were correct through out, from RPC thru cables to motor.

I cleaned out and warmed up all the grease from bearings.

It still lags and slowly gets to full speed.

I’ll try and post a video.

I did end up buying one of the ones you posted got it for cheap too.

Wrong shaft size so have to find a pulley or modify the one I have.

Same thing happened to the new motor when I tested it out it was slowly turning until I switched a leg around.

Got me thinking I did the same so as stated before ended up making sure I tried T1,T2,T3 is different positions.



Sorry no video

 

[Scra99tch]

Seems to me that we had a motor that was rewound so it was only 440V. Something that was done because all we had was 440 and it was cheaper / easier. Thought that you were getting a new / different motor? I will look to see what I had found to verify coils locations after Christmas.

Alright new motor installed. Ran motor directly from phase converter and there was the similar slow running behavior. So I thought I had the leads switched around, swapped two of them and motor ran full speed.

Finally got around to installing and wiring it up on the machine. Knowing which wire coming into the box was T1 T2 and T3 and connecting those to the correct windings on the motor. Followed it from the American rotary phase converter into its control panel.

Same thing is happening. It is rotating slowly just like the old motor. I am thinking that the same thing will happen after tripping a few times and warming up then it would eventually get to speed (But I am not going to do that to this motor).

What could I look for inside the control box that might be causing this? Bad heaters possibly? Some internal corrosion I have not seen?

 

[OTmachine]

Switching L1,L2, & L3 around should have no effect other than reversing the direction of rotation. I think that if you have a lag one way and not another way, then you have a partial open or a short, which would mean that your motor needs repair. IMHO, it would be best to take your motor to a motor shop to have it tested. This would take one possible problem out of the loop. You need to have known Good components to verify problems.

 

[Scra99tch]

I'll trouble shoot the old motor at some point but the brand new motor (It is new-new not new to me) is doing the same thing. I'll try hooking up old motor just to RPC see if it runs full speed.

Something in the magnetic controller is causing the problem. How would you know a heater has gone bad?