Bafang CST 500W 48v to 36V

[marcoredit]

Hi,

I've installed a Bafang 500w Cst 48v with a 36v controller and 36v battery, but it doesn't work.
I've tested all the cables with a multimeter, from controller to the Bafang motor, and everything is fine.
The battery has 41V and works great.

Is there something else that I have to check?

Thx.
Mark

 

[d8veh]

Which controller is it? Did you connect the thin red ignition wire if it has one? It would probably save a bit of time if you dhowed a photo of all your controller connections.

 

[dogman dan]

You may also need to find the right order for the phase and halls wires. It may not be bb gg yy.

 

[marcoredit]

Hi,

I bought this controller http://www.aliexpress.com/item/36V-48V-500W-12mosfets-electric-scooter-motor-controller/1351616109.html

I connect the red ignition.

Do you know the right order for the phase and halls wires or I have to try?

Can I measuse the volts that come out from controller with the battery plugged and the throttle to maximum.


Thanks you.

 

[d8veh]

Whatever you do, don't give more than 1/4 throttle until you have the motor running smoothly, otherwise you can blow the FETs in the controller. You cannot measure anything on the phase wires with a meter. You need an ebike tester:

http://www.ebay.co.uk/itm/1PC-24V-36V-48V-60V-Car-Scooter-Brushless-Electro-E-bike-Motor-Controller-Tester-/181246430524?pt=UK_Motorcycle_Parts&hash=item2a33210d3c

You have to join the red to the purple on the "power lock" connector. If it doesn't work after that, go through the 36 phase/hall wire combinations.

 

[marcoredit]

Thanks for the reply

What do you mean for power lock connector?

 

[d8veh]

If you look at the Aliexpress listing that you linked to above, there's a photo with all the cables labelled. It's the two-wire one at the top of the photo with red and purple wires.

 

[marcoredit]

I have joined the red to the purple on the "power lock" connector, but when i connect the battery there are sparks! What have I done wrong??

Thanks for the patience...

 

[d8veh]

It's normal to get a snap noise and spark when you connect the battery to a controller. It should only do it once. If you touch again immediately after, there should be virtually no spark. If it's like that, everything's OK, and it will now work. If it sparks each time you touch, something is wrong.

The spark is due to the capacitors in the controller that charge up instantly, so they draw a very high current like a short-circuit for a very short time. Once charged, they don't take any more current.

 

[marcoredit]

Snap noise and spark happend everytime I try to connect the battery, but after 3 times I connect it without sparks.

Now there is the sound of the motor but the wheel don't spin... Do you know why?

 

[marcoredit]

I invert the phase colors, now I't seems to work.

It's possible that the motor works and spin right, but the phase are not correct? Because It seems like motor scratch in different phase connection.
I don't wont to burn something!

 

[d8veh]

You have to find the correct phase and hall sequence for the motor to run smoothly in the right direction. Don't use full throttle until you get it right. There's 36 combinations.

 

[marcoredit]

I find the correct phase and hall sequence

Phase
Y -> Y
B -> G
G -> B

Halls
R -> R
BLACK -> BLACK
Y -> B
B -> y
G ->

Thanks b8veh!!!