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I have made an electric go-kart using a 2000W BLDC motor, 48V 45.5Ah Li-ion battery and 60A 48V rated controller.
The kart moves properly, but if the acceleration pedal is given a sudden jerk (which happens often), even if it is small; the circuit gets cut-off. The on-off switch has to be on-offed again to make the kart start.
However, this problem only occurs in loaded condition i.e. on the road. In static condition no such problem occurs. I have also connected a 50A rated fuse, which is yet to burn-off despite the motor having a 60A peak rating.

I think there might be a problem with the acceleration pedal that it is not rated for this 60A current, but am yet to verify it. What is an acceleration pedal made-up of, a potentiometer? How can I make one DIY style?

What could be the possible problems? Or any ideas or solutions that I can work on. Please reply asap, its urgent.
 

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your controller might not be able to handle the 60a it is rated for.
you could put a block of wood under the pedal so that you can only press it to the point just before its tripping out.
the pedal just sends a signal and doesnt carry current so it wouldnt be that
 

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Discussion Starter #3
Thanks @arklan for the suggestions.:)
Yes, I think their might be a problem with the controller itself.
Regarding placing a block of wood under the pedal, have tried it millions of times with varied sizes of blocks. It either reduces the speed we are getting or in most cases, it just gets cut-off.
Have tried to find the point where it gets cut-off but there seems like there is no such point because in most cases it gets cut-off when sudden acceleration is applied.

How do I test the controller rating when motor is in loaded condition?
Usual ammeters or multimeters are not made for 60A, so any advice?
 

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Hi
From your description of the problem I would be looking at the throttle itself

There are two common throttle systems - a variable resister and a hall effect system
I do not have a single clue about the Hall effect but the variable resister is both easy to understand AND subject to the type of faults you report

Disconnect the throttle and have a look at the wires going to it - use a multimeter set to resistance

Most will be zero power at zero ohms ans full power at 5000 ohms
connect up the multimeter and play with the throttle
If you get occasional readings a lot higher then there is your problem!

Most controllers use zero to 5k Ohms - but they also have a "broken circuit" detector so if the throttle goes above about 6 kOhms (6000 ohms) the controller thinks there is a broken wire and shuts down
 

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Just a guess, you may be sagging the battery voltage enough to cut the controller off.

Sent from my STV100-1 using Tapatalk
 

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Discussion Starter #6
Tried a few other things.

Used a multimeter to check tge currents in loaded condition,the voltage is fine but the current only reaches a maximum of 25A just before cut-off. Our battery and controller are both rated for 60A, then why does this occur?

Used a controller rated 48V but 40A and it cuts-off the circuit even in no loaded condition.

The throttle I am using is Hall-sensor type. Will try using a 0-5kohm rated potentiometer next.

Initially, while buying the motor and controller, originally the controller compatible with the motor was one which was rated at 80A. Got it downsized to 60A due to the rules of the competition of max current allowed being, 60A. Could that be the problem??

Thanks for taking interest. Please help.
 
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