bafang mid drive died in service

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OK, you need to discharge and charge the battery every 2 or 3 months as you don't use it.
Best is, to charge it for 80% as you store it for a longer time.
But after 6 years it is good.
 
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Apr 15, 2013
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Well I installed the new lipo4 battery and new controller in the BBS02 mid drive
display shows fully charged battery but motor still refuses to work.
discovered when I connect the motor to battery, I get a spark. Must be a short in motor. Could have been issue all along?
I checked and rechecked all the wiring. Can't afford to put out $450 for new motor so I plan to use my hub drive trike for now but I recall an issue with the front axles?
Will check tomorrow morning.
 
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A spark in the motor or where you connected the wires?
I don't know if it is brushless, because then you can't connect the motor to the battery without an esc.
 
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I get the spark when connecting the motor to the battery.
I though about a capacitator so I shorted the two motor wire together and then connected correctly/ Still a spark which would indicate a short in the motor.
Maybe I fried a winding inside the motor so new motor on want list.
Yes brushless motors have windings inside.
 
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I though about a capacitator so I shorted the two motor wire together and then connected correctly/ Still a spark which would indicate a short in the motor.
If shorting the motor wires drained any integral capacitor, there would be maximum spark when you reconnected as the capacitors would be empty and ready to take on the maximum of what they could get. I seem to recall there being a fuse somewhere in the system (inside the battery pack?) and that should protect the battery and what is connected to it.

Can you take a resistance reading across the two motor wires with it disconnected? I will then be able to compare it with mine. It might help.
 
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will get a reading tomorrow. I have a dentist app in the morning.
 
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South Benfleet, Essex, England, UK
I get the spark when connecting the motor to the battery.
I though about a capacitator so I shorted the two motor wire together and then connected correctly/ Still a spark which would indicate a short in the motor.
Maybe I fried a winding inside the motor so new motor on want list.
Yes brushless motors have windings inside.
My Bafang ALWAYS produced a spark when you connected the battery. Nothing wrong with it though it all worked fine.
So did the hub motor on Loki produce a spark at the battery connector as you attached it. I think this is perfectly normal TBH.
 
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Ordinarily, one wouldn't connect things with the power turned on and would not see any sparks that would normally be hidden within the internals of the power switch. Any capacitance within the connected circuit, at the time that the power is connected to it, is charged up to the applied voltage and can raw significant current for a very short time. I haven't had a chance to check mine yet but there is a sizeable spark when connecting the charger. After all, there can be anything up to 42V at the connection point.
 
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Mr. Idaho: I did it yesterday.
Resistance measure on power wires with them disconnected from battery: OL (infinite)
Turned battery ON, crossed fingers and re-connected motor to battery: A very healthy 42V spark ensued.
Turned controller back on and was relieved to find that it still worked.

Haven't reread. Does your controller light up?
Are there any error messages?

FWIW: I had a "dicky" speed sensor connection once, twice, thrice (until I fixed it) and got its error message. It's not supposed to work with such error message but it does. Only problem is you can't change assist levels but, you still have assistance at whatever level it was set at before the sensor disconnected. I think it may also have been possible to stop, change it, and start of with a new level.
 
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A drive motor (and probably the controller itself) WILL NOT normally be started by the controller IF it thinks (for example):
  • A brake lever cut-off switch is operated.
  • The "thumb throttle" is at a non-Zero position.
  • It thinks the speed sensor is disconnected.
The controller goes through a series of status-checks before livening up the display board and showing "useful" info.
On a Bafang the controller is in the motor housing, the display console is just a serial connected display device.
If the display is blank; either it has signal on the serial links but no-power or vice-versa.
 
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I definallity have a SHORT in the motor.
connected ohm meter and bam, it is a shorted motor.
Yesterday I received my BSHD mid-drive and plan on installing today.
 
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