Can controller make geared hub motor slip?


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I installed a bafang 36 v geared hub motor 8/21 on my ebikeling controller. It worked okay but I had 25 watt resistors in phase wires to drop voltage from 48 to 36 and one burnt out 4/5 of way to summer camp.
I bought 110 watt resistors and installed them but the ebikeling controller started producing "07" error whatever I did. No contact to motor windings is error 02. 07 was error when PAS sensor was not plugged in. Couldn't repair it, a new PAS sensor didn't work and setting P10 to throttle only didn't make 07 go away. No wheel motion. So I bought a "500 w ebike scooter" controller. Has taken me 6 weeks find out how to power it up. 48 v to the unlabled (not even in chinese) red wire makes the throttle work.
But when the motor spins, it doesn't turn the wheel. Whirr and no motion. Reversing 2 phase wires makes the noise ratchety instead of smooth, but the wheel still doesn't spin. Same motor as worked last August with ebikeling controller.
Changed the motor today to another Bafang 500 w geared hub. Same symptom, whirr and no spin of the tire. Ratchety sound if I reverse 2 phase wires. ??? These are the motors from with 9 pin juli connector. I converted the first one to 6 pin rectangular connector last year to work with ebikeling wiring, before the juli-6pin rectangular converter harness rode the slow boat from China. It worked that way before the ebikeling controller *****ed out.
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I think you are on the right track assuming that the "whir" but no motion is the motor running backwards. "Ratchety sound if I reverse 2 phase wires" leaves me clueless.....

Is this a sensorless controller, or are you using sensor wires? If using sensor wires, are you switching those to match your changes on the phase wires?
Motors can run backwards inside a geared hub. I've flipped the two phase and two sensor wire intentionally (bottom of diagram) to see what it's like. It's strange,

Or you could have worn out the clutches, but I would expect some movement if the wheel was lifted.
Is this a sensorless controller, or are you using sensor wires? If using sensor wires, are you switching those to match your changes on the phase wires?
6 pin rectangular connector has red & black one side, blue green yellow other side. Blue yellow green read 1.2 on diode scale to the black wire. Thin wires.
After posting tested 3 phase wires for ac voltage when throttle was activated. All 3 had ac voltage on them.
Next will try reversing 2 phase wires, also same color sensor wires. Or if I can figure out the chinese labels, activate the reverse input. Some of these scooter compatible controllers have a reverse input. The English documentation of connectors & wires is unavailable on the controller I bought.
Tested clutch unpowered. Rolls easily forwards, drags and noise in reverse. Both motors.
Was no yellow+black 2 pin "reverse" connector. Is grey black 2 pin ????.
Okay, swapping 2 phase wires & two sense wires made wheel stick. Swapping 2 other phase wires made it rotate forwards. thanks for diagnosis chart.
One other question. This controller has a 3 pin rectangular block, female pins, blue brown black. Might be 3 speed input. Blue & brown are +4.9 v to black. How does this work? single pole double throw switch, black to middle, one pole makes slow, other pole makes fast?
This is not my controller, just something close. My operating system didn't have screen capture when I bought the 500 w controller that is working now.
If I don't thank you promptly I went out to summer camp for a few days. Wife took me & 60 lb supplies out Monday in the car; grass on driveway was above my navel. Been trying to get out there for a month but am not in shape enough to take the back way with 80 hills without a little help. Hwy 3 berm has gotten too rutted to use the last 7 miles.


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