electric bike not working

[Mggt]

Help I've got an electric bike that won't work it was working fine then all of a sudden gave up. I can spin the pedal fine when battery is not connected but as soon as I connect it it feels like the the wheel is jamming. I was wondering if it could be the hall sensors. I don't know what bike it is but can send you a picture of it and a picture of the motor. Thanks

[Bikemad]

Please provide as much information as possible.

Is it front wheel drive, dual drive, crank driven, or rear wheel drive?

Does the bike have a manual throttle (twist or thumb?) or is it controlled by a pedal assist sensor on the pedals or possibly a simple torque sensor unit incorporated within the rear wheel sprockets?

Is the motor's electronic speed controller mounted somewhere obvious, or is it hidden within the frame, battery holder or possibly inside the motor itself?

How many wires are connected to the motor? (E.G. Three thick wires and five thin wires etc.)

If you can post some pictures clearly showing the various components and wiring connections, it will help to give us a better idea of what system your eBike uses.

Alan
 

[Mggt]

Sorry for the late reply.
Its rear wheel drive.
It has a manual twist throttle but u have to pedal before the the throttle will work. It also has pedal assist.
The speed controller is hidden in the frame below the battery,  its connected to motor by 3 thick wires (yellow, blue and green) and 5 thin wires (yellow, blue, green, red and black.
I know at least 1 hall sensor is damaged but don't what hall sensor I will need 4 my bike. All I no is its 36v and the speed controller is Chinese.
On the speed controller it says
WZK - 705 SD
36v
14.5 A
31.5 + 5.0
0510019 BELS
And a bar code with the number D0511180313

Many Thanks
Louise
 

[Mggt]

Pic of motor

[Mggt]

Speed controller

[Mggt]

Throttle

[Bikemad]

Hi Louise, unfortunately the pictures of the stator are not clear enough to be able to see the actual Hall sensors, but I would expect them to be the most commonly used SS41 Hall effect sensor.

Have a good look at how the sensors are fitted into the stator assembly and make sure that the new ones are fitted in the same orientation and with the correct wiring connections to each sensor. (+5V red wire, 0V black wire and the Yellow, Green and Blue signal wires)



If you are unable to take a clear photo, draw a detailed diagram of the existing connections on a piece of paper to ensure no mistakes are made with the wiring. 

As one sensor is already damaged, it would be advisable to replace all three sensors while the motor is apart, and hope that it cures the existing fault.



Alan
 

[Mggt]

Hi I've replaced all the sensors and it's still not working still jamming. Do you have any other ideas as to what it could be all it says on the bike is electro power so don't know what make it is. I think it's a Chinese bike
Thanks
Louise

[Bikemad]

Hi Louise,

If the wheel is jamming internally (i.e. it is not rubbing externally against the frame or brakes etc.) when you spin it by hand without using either the throttle or pedals then I would say that the controller is the most likely cause of the problem.

However, if it doesn't jam when you spin it by hand, but only jams when you pedal it, it could be the Hall sensor wires (or phase wires) are connected incorrectly.
If unplugging the Hall sensors stops the jamming, this would indicate either a problem with the wiring or the controller.

It might be worth checking that the new Hall sensors are all working correctly, as sometimes they can become damaged by excessive heat if you take too long soldering the wires on. 

Take a look at this post and this video for details on testing the operation of the hall sensors.

If all three of the Hall sensors are working correctly (and the Phase wires and hall sensors wires are definitely connected correctly) then you will probably need to replace the controller. 

Alan

[Mggt]

What voltage should should be going through the 3 thick wires to the sensors pls

[Bikemad]

The three thick Yellow, Green and Blue wires are the Phase wires that supply a sequence of switched voltage pulses to the three sets of coil windings in the stator, the intensity/duration and sequence speed of the AC voltage pulses on these wires will vary in relation to the the wheel speed, the throttle position and/or the pedelec output.

With the throttle released (and the pedals stopped) there should be less than 1V when measured between the black battery ground connection and each of the phase wires.

The thin Yellow, Green and Blue wires are the Hall sensor output wires, and these should switch regularly between 0 and ~5V when the wheel is rotated slowly by hand (measured between the thin black wire and each of the sensor wires.)

Alan
 

[Mggt]

I replaced the hall sensors and my bike was still not working so I bought a tester. After testing it it looks like I need a new throttle, controller and hall sensors. I've looked online 4 a controller exactly the same as mine but can't find 1. How do I find out what motor eg. 500w so I can buy a controller that is compatible with my motor. And please could you tell me, if my bike is 36v do I need 36v sensors.
Thanks Louise