Replaced Magic Pie 5 Hall Sensor but motor shuddering and won't turn over

[Nsteck17]

Hi,

I got the Magic Pie 5 and was riding up hill when suddenly my bike gave out.
I rode it down hill and noticed when I pedal some I could still use the motor.
With the error code on the display and this information I was able to figure out it was most likely a hall sensor failure.
Thanks forums!

I read the forums, got the Honeywell SS41s that everyone mentions to replace them.
Swapped out all 3 sensors so they'd operate the same.
Put the motor back together and now when I hook everything up I get a shuddering motor that won't turn over. Video below.

https://www.youtube.com/watch?v=i8G9Fik-feY&feature=youtu.be

I've tried giving it a spin to start with but still no luck. It seizes up immediately still.

Also tried:
1) Flipping the middle sensor (someone said that somewhere)
2) Checking the voltage. Some reason they all came back ~0.0v to ~3.3v
to read the voltages I put a tiny nail in where the sensor wires come out of the controller when connected and I assume that's the reason for lower voltages.
They all switched/latched when I'd pass a magnet over and connected the battery. They seem ok, so I'm pretty sure I wired it up ok.
3) Installing the stator backwards


Still yet to try:
4) connecting the phase wires and feeling for resistance (heard this helps detect bad motor coils and/or phase wires

Anyone else have suggestions or have seen this issue before and know what I screwed up? I write software, I have to admit I'm not the most savvy with hardware.
My next options are:
A) to replace the controller with the external one that works without hall sensors
B) try another hall sensor
C) give up because if a motor coil is broke I'm screwed? (which I'm worried is the cause since it won't fully turn over)

[Bikemad]

If the Hall sensors are all located in their slots the right way around and connected to the correct coloured wires, it could be that the phase wires have simply been reconnected in the wrong order on the controller.

If you're lucky, it should be possible to cure the problem by putting the phase wires back in the correct order.





But if you're unlucky, it can sometimes damage the controller if too much throttle is applied while the phase wires (and or Hall sensor wires) are connected in the wrong order.

It is unlikely to be the stator windings as I don't recall hearing of any winding failures whatsoever on any of the Magic Pies, but it wouldn't hurt to try the simple test of touching each pair of wires together and checking the electromagnetic resistance on the motor to confirm that it is the same for all three combinations (Yellow>Blue, Blue>Green and Green>Yellow).

If you do decide to go for an external sensorless controller, be aware that the motor will be a lot louder than it originally was, unless the new controller also uses Field Oriented Control vector technology (Sine waves instead of square waves).

Alan
 

[Sam.Vanratt]

Hi Alan
are the pole shoes really not insulated? The yellow one seems to touch the Elko near to him, which typical (for small capacities) are not insulated but have a hard wiring to the negative pol. I wonder why there isn't a simple shrinkable tubing around it....
I'm not sure if sensorless is even possible in Delta configuration. "Sensorless" use one pole always to look into the postition, while two work which is easy as star, but delta?
Cheers
Sam

[Nsteck17]

Oh wow... I took a picture before I unplugged everything. I didn't take a clear enough picture.
You're right that I had the phase wires mixed up.

I switch the blue and the green and success!

I feel so dumb know - thanks for the couching. I'm so happy to see it work!

[Bikemad]

Are the pole shoes really not insulated?

Sam, the phase wire terminals cannot move when properly tightened up and therefore should not be able to touch against anything that might cause a short circuit etc.
 
The capacitor (Elko) shown in the photo does actually have a thin protective heat shrink cover on the outside of the cylindrical body, and the exposed terminal on the yellow phase wire was not as close to the capacitor as it appears to be in that photo.

Are you sure the MP5 has Delta windings not Star? I am pretty sure that the stators on my MP4 and Magic Pie edge both had the additional sleeving where one end of the three phase windings are all joined together, which indicates to me that they both have Star configured windings.

The high torque output and unloaded rpm similar to the MPIII would also seem to indicate that it is Star wound not Delta.  Delta configured windings usually have a much higher maximum rpm, but with significantly reduced torque.

I was told by GM that the only difference between the MP4 and the MP5 was the Bluetooth compatible controller and Bluetooth dongle, therefore the motor (and stator windings) should be exactly the same.

You're right that I had the phase wires mixed up.

I switch the blue and the green and success!

At least it was an easy fault to fix. 

Alan
 

[Sam.Vanratt]

Hi Alan
No, I mixed both words up. Star is the Higher Current version (lower R) with higher Torque, while the Delta is more Switch (lower Current) friendly; the RPM should normally be the same as they depend on the "switch" frequency (as all polyphasic motors).
It's good to know that the Cap is insulated (in the pic is doesn't look like) as a pole going loose is not so rare due to the rattling.

Cheers
Sam