Ebike shuts down at max throttle.

[MadeInXina]

Hi, I own a makeshift ebike and currently have a 350w motor running with a Brainpower 48v controller and s866 display.
The battery I'm using is a 10ah 48v battery.

Whenever I try to go above 25kmph, my s866 display shuts off showing Error 06 (low voltage cutoff). This issue has only started recently and at first, I thought my BMS might be faulty causing it to automatically shut off the battery. This even occurs when the battery is fully charged (54v) which is certainly odd as the low voltage cutoff should be at around 39v.

Whenever I give full gas, the S866 display shows that I'm consuming 4000w-5000w which is very odd as I'm running a 48v battery with a current max of 13A.
Could this be a faulty hall wire sensor or wiring issue or would the issue lay with my battery?

Thanks in advance for any comments

 

[cyclebuddy]

If the display cuts out too, it does sound to me like the battery is shutting down. Using full throttle places a huge current draw on the battery: Even if your battery managed to cope with that demand when it was new, as the cells age/wear they become less likely to cope, dipping voltage to below LVC. How soon that begins to happen depends a lot on the quality of cells being used.

 

[Benjahmin]

Yep, sounds like the dreaded voltage sag. Battery not capable of providing current being demnded, voltage collapses and battery management shuts the battery down until the voltage chemically recovers to within operation parameters.
Temporary solution - don't use the throttle.
So is it the battery that's 13A or the controller? The battery needs to have a continuous A rating higher than the controller maximum A rating.

 

[Nealh]

How old is the battery and it spec's ?

 

[MadeInXina]

Battery is a few months old but what I find weird is that my display says I'm using 5kw at max throttle when I only have a 350W motor. Is it even possible to draw 5kw from a 48v battery with a capped current of 13 amps from the side of the controller? Could it be a wiring issue?

 

[Benjahmin]

Motor wattage rating is irrelavent, the motor will take whatever is fed to it by the controller.
5Kw at 48v is 104A - that'll do it !
What is the power reading when using pas? Does the same thing happen or only on throttle?

 

[MadeInXina]

I don't use pas at all as I have no pedal sensor. I switched back to my old 36v 6ah battery and bike seems to work with no problems at all. Power reading is still 5kw but I'm not sure whether this might be incorrect as I am getting normal range and no overheating issues at all. I might have been my 48v battery after all.