Kollmorgen motor

[Harold in CR]

I have searched both on the search here and Google search, both using E-S and without.

My problem is, My Kollmorgen motor had the magnet ring come loose from the rotor drum. Of course, it wiped on the laminations. Is it likely that the laminations are shorted, and therefere, I can't get Phase readings on the motor-hall tester, when I turn the shaft ? These motors have some serious cogging, so, am I screwed or, is it possible I can do some careful cleaning of the laminations, and get the phases working ??

I get absolutely NO leds to even flicker when turning the shaft.

I got all the halls working, finally, and just need to get the correct position for them, and build a little holding bracket for the circuit board with the halls mounted. Now this phase problem.

I have cleaned the rotor drum and the inside of the magnet ring, and glued it all back together. There is a crack-opening of the magnet ring, so, I carefully cleaned it and made sure it had good contact, so I had compression all around the ring while the glue dried. I had to sand a tiny bit off one side of the crack, so it didn't "tick" as I turned the shaft.

Any helpful ideas would be greatly appreciated. Thanks

 

[Harold in CR]

I have taken the rotor out of the motor housing, sandpapered all the ends of the lams, with fine paper, VERY carefully, and cleaned thoroughly with alcohol. Then, blew the housing out with 120PSI air pressure. I have verified that each lamination has a gap from each lam next to each other. There is NO shorts between lams, as far as I can find. I put the leads of the multimeter on each end of each set of lams, and get an ohm reading , VERY slight, 1.0. I'm thinking that's phase winding resistance ?

Meter is on the 200ohm scale and reads 1 on the far left of the screen, before touching leads together. Toughing leads together = 0.

Then I tested each phase to case. OPEN V, NO shorts. Then, I tested each of 2 phases and get 1.1 on any combination of phase to phase.

Installed the rotor and still NO flicker of the LED's on phase testing turning the rotor.

Only thing I have NOT checked is V across phases or phase to case.

What could possibly be the reason I get no flickering of the LED's ? I am going back out and test for V on each phase leg, then, hook the thing up and see what happens.

 

[knoxie]

Hi

Yes I have done this to 2 Kol motors myself, I used to run them at 1.5KW and whilst they work well the magnets tend to split and crack from a combination of the high RPM and the heat, if you are lucky the glue just breaks free and you can slide the magnet off the rotor intact and glue it back on.

You should get a reading off the halls regardless of the phase connections on the motor, the halls are detecting the magnet poles on the rotor ring, are you sure that you have relocated the PCB assembly correctly? if its too far off it wont work.

I have to repair one myself as my KMX motor has the same problem, I have got some liquid metal epoxy to fix it up, luckily I have a box of 10 motors new with controllers so if I am feeling lazy I can simply fit another rotor, they are great little motors though so well worth trying to fix it, can you post some pictures of the motor and rotor and provide some details as to what controller you have on it etc and what power level that you are running it at?

Just re read your post and I see that you are using a tester on the phases, hmm again can you verify that your controller is working and or your tester is working :?

 

[Harold in CR]

Unfortunately, I believe the controller is not working. I tried to get my new hubmotor to at least flicker. Tried all phase combos and nothing. Also have steady V readings on throttle leads. Not toggling at all.

Took a couple photos of the new backer board I built. It will probably get soft IF I ever get the motor to run, so, I am going to cut out a third of it, and also drill holes in the front of the housing. I already drilled the back cap.

Knoxie, could you tell me if you have that white tape covering a few stator teeth, and, is it in relation to hall position on your motors ? Thanks

 

[John in CR]

Some motor need more rpm than others to register on the tester. It's reading BEMF from each phase. A big hubbie doesn't need much rpm, but I remember needing to spin an RC motor pretty good. The hi-Koll is probably more like the RC motor in that respect.

 

[Harold in CR]

I had the motor with the shaft hanging off the edge of the workbench. I have a flat spot ground into the shaft for 2 allen set screws to jam against.

I pot an 8" crescent wrench on the shaft, engaging the flat, and whipped the wrench like starting a model airplane fuel engine. Still no flickers. I DID get V readings off the 3 phases on the VOM.