BBS02B - possibly short-circuited?

[eevermind]

Hello dear community,

I am currently building a commuter E-Bike but ran in an issue. Due to buying the battery separately, the connectors on the Motor and battery aren´t compatible, which is why I bought a XT60 to bullet connector-adapter. I had to crimp down the connectors for the wire to sit tightly, but didn't think to isolate them before testing.
In order to test the system, I connected the motor to the display on the one hand, and to the battery on the other hand.
As soon as I turned on the battery, there was a spark and some smoke, the battery connectors seem to have melted a little as you can see in the attached picture.
Now, the battery still seems to be working fine (indicator bars showing), but the motor obviously doesn´t.
Is my suspicion correct, that I fried the controller in the BBS02B and need to replace it?
Would just isolating the connectors with some tape do the trick next time, or is it recommended to solder and heat shrink the connectors?

Your help is much appreciated,

Daniel

 

[saneagle]

Shorting the battery wires wouldn't normally do any harm to the controller., sice the power doesn't go anywhere except between the connectors. Does the LCD work properly after that?

With ebike electrics, you should never have both positive and negative wires unprotected at the same time.

 

[eevermind]

Well, I tried with two separate displays, but couldn't get any one to turn on.

 

[guerney]

I murdered my BBS01B's controller similarly - while trying very ineptly preparing to solder my battery to my controller, I knicked tiny knicks into the insulation of the battery wires by accident with one of those Poundland disposable bladed products. There was a spark and bang between those knicks, and my controller died a tragic death. Dead display. The seller first asked if I had another display - why the heck would I have anther display kicking around, I replied. I was then instructed by the seller to test for 5V at the speed sensor - no voltage detected, the seller reckoned it was dead. Controller was confirmed dead at the seller's lab or office, after posting back to China. As per @peter.c's recommendation, I bought a new controller from Greenbikekit, connected it all up, was right as rain.

Shove in paperclips, easier to measure, the seller said.



My wire stripping and soldering skills have much improved since! And he sent me a free controller, which I keep as a spare.

 

[saneagle]

Well, I tried with two separate displays, but couldn't get any one to turn on.

The displays are connected directly to the battery - nothing to do with the controller. If they don't switch on, there's something wrong with the battery supply to them. The thick wires go into the controller, then two branches are taken off on the controller PCB, which run up to the LCD to power it. Did you check the voltage on the two battery wires going in? Do it first disconnected, then connected.

 

[guerney]

In my case at least, the display was fine, it was deffo the controller - perhaps if any function such as speed limit is designated to the display by the controller's firmware, the display won't switch on because it's waiting for data/communication (or flags up an error and halts) from the dead controller via the 5 wire cable? I didn't bother to attempt testing for power to the display, because under warranty it was the seller's puzzle to solve.

 

[saneagle]

In my case at least, the display was fine, it was deffo the controller - perhaps if any function such as speed limit is designated to the display by the controller's firmware, the display won't switch on because it's waiting for data/communication (or flags up an error and halts) from the dead controller via the 5 wire cable? I didn't bother to attempt testing for power to the display, because under warranty it was the seller's puzzle to solve.

The display has to be switched on to communicate, so no communication can prevent it from switching on. As I said, the switching circuit is connected directly to the battery and powered by it. All the other stuff happens after it's switched on.