BBS02 sudden cut out

[Carrotious]

Good morning,
I have a feeling I may have blown my controller on my new BBS02.
I was ridding up a hill fast and the engin just stopped.
The eggrider display went to 0v for the battery then sort of came back up slowly to 30v (I have a 48v battery)
I unplugged the battery and recharged and left everything overnight.
Plugged in again and started eggrider.
It starts up, the voltage increases on screen to 32v then the display shuts off.
Is there a procedure to confirm it is the controller?
I've had a look around but haven't found a whole lot of specific info.

The motor really wasn't that hot to touch.
I was running 25A.

Many thanks for any help,

Giles

 

[Atak_Snajpera]

Maybe you have unbalanced battery or damaged battery. Your BMS is designed to cut power at 36.4V so no wonder everything shuts down at 32V. What did you expect? Running all the way to 0V?

If controllers dies then eggrider shows FF error (no communication with controller)

 

[Carrotious]

ah a misunderstanding.

I had plenty of battery left when it cut out.
0v was the reading on the display immediately after the cut out.

Now when I switch on the battery shows 56v (when it does switch on, which is not every time)
Then the volts start cycling down till about 30v then the display cuts off.

Thanks,

Giles

 

[caleb7]

Anyway that still looks like BMS cutting off for some reason. Maybe there is short somewhere in the motor (FETs died?).

I'd try to power the controller from another source (like the charger itself) and see if the same happens. But be careful not to put the voltage reverse, the controller will be damaged surely even if it is fine... In fact I'd put a fuse before going into bike too, too protect the charger/power source if there is a short.

 

[Carrotious]

ok i have a variable voltage DC power supply that I could use-

I guess I set it at 50ish volts straight to the motor cables red and black?

Then switch on the display and see if the voltage holds?

Thanks for your help

 

[Carrotious]

Maybe you have unbalanced battery or damaged battery. Your BMS is designed to cut power at 36.4V so no wonder everything shuts down at 32V. What did you expect? Running all the way to 0V?

If controllers dies then eggrider shows FF error (no communication with controller)

ah didn't read your last line... Indeed, the controller shows FF error

 

[Carrotious]

so I tested the motor with the charger.
display starts up voltage 57v
bike runs for a short time then the voltage cycles down to 30, the speed goes to --.- and there is an FF error.

looks like the controller?

G

 

[caleb7]

Seems like battery isn't the issue then. Does the motor ever turn or not at all? Not expert enough to tell about the controllers, but that may give some clue.

 

[Carrotious]

Yep the motor turns for a little while on the throttle.
The moment I let go the throttle the display voltage drops and then the display cuts out.

 

[Atak_Snajpera]

Can you check voltage at the battery with some multi-tool?

 

[Carrotious]

53.3v

 

[Carrotious]

More or less fully charged

 

[amberwolf]

If the battery actual voltage read with an external voltmeter stays the same while the display's voltage does not, then the two most likely problems are a connection fault between controller and display (anywhere from controller PCB to wires to connectors to wires to display PCB) or a connection fault between battery and controller (usually at the connnectors, but also anywhere between them, past the point at which the external voltmeter is connected and showing the correct voltage).

If the display also shows communication errors of any type with the controller, it probably is in the controller/display connection, since that also affects comms.

Since it happened under high load, a battery connection fault is more likely, and could even be at the shunt inside the controller (poor solder might have melted and left a partial connection from the shunt to the PCB).


It's possible the display or controller has actually failed, but it's much more often the connections or cables.

 

[Carrotious]

ok thanks that explanation.
I've contacted the seller and will go through the process with them and hopefully there will be a positive outcome.
G

 

[tomjasz]

I had plenty of battery left when it cut out.

How do you know that? While learning to trouble shoot I learned about Watt Meters here. The WM has saved my bacon more than once and reveals more info than EggRider.

You don't tell us how old the battery is or who but the battery. More than a few times, for me, your issue was battery sag. Something you could see real-time values for with a Watt Meter.

​

 

[Carrotious]

How do you know that? While learning to trouble shoot I learned about Watt Meters here. The WM has saved my bacon more than once and reveals more info than EggRider.

You don't tell us how old the battery is or who but the battery. More than a few times, for me, your issue was battery sag. Something you could see real-time values for with a Watt Meter.

​

brand new battery, brand new motor...
battery reads 53.3v after charging with the multi meter.

 

[Carrotious]

PSWPOWER has offered to replace the controller, should be here within a week...