Regen braking fried my controller

[nejccesar]

Hi,
I have upgraded my golf cart to a 100Ah LiFePO4 battery pack. After upgrading and charging my battery pack to around 80% full, I went downhill on a local hill. The controller instantly fried. I have read afterward that this is due to regenerative braking and the LiFePO4 battery pack not accepting the voltage, which fries the controller.How can I disable regenerative braking if I order a new controller? I am posting photos of the wiring and the fried controller in the attachment.

Thank you for your time and help!

[scottyb]

Regen braking can be turned off in an Alltrax XCT controller. However, I'm unsure if that stops the motor from producing regenerative power. That is good question for the Alltrax support crew. Call 541-476-3565-3 and post their reply here

[TheCartBoy]

In my experience with AC drive, specifically the RXV. There needs to be something to absorb the energy produced by the motor. The lithium battery essentially disconnects itself from the circuit, when that happens the voltage on B+ increases rapidly, like 100V! This will easily destroy the controller. On the RXV, there is a larger resistor attached to the controller that will turn on when the voltage starts to get too high, this protects the controller in this situation. But until it's retuned for your BMS shutdown voltage, it may not protect the controller soon enough.

How fast were you going down the hill? Probably more than the regular speed limit?
That could also wreck the motor.

[InvalidUsername]

That controller has the same pinout as a 1266. In it you can turn off or minimize regen via the braking parameters

[InvalidUsername]

What cart do you have that has that obscure controller?

[Volt_Ampere]

What's the voltage rating for that controller? Also, if the BMS shuts down due to over voltage while you are driving, the inductive voltage spike can kill the controller. (Unless you have a protection diode on the big terminals of the solenoid)

[nejccesar]

I really dont know what golf cart I have, there are no markings, i assume it's an older club car.

Alltrax would be a solution but 700€ is a little bit too much atm.
Looks like the controller is the same as Curtis 1266, just from a different company. If I program the controller Curtis 1266 with a PC software to not activate regen braking, will the motor still brake and make Voltage? Because that would be a solution, I would much rather change brakes every few years than buy an expensive controller. The cart is driven around 2 months total per year, but it has a very steep hill.

I really did not go fast maybe 5mph downhill.

[nejccesar]

Is it possible to just remove the electric brake from the motor? See the attached pics of my motor. Should I just remove the silver bit? or somehow disable it?

[Volt_Ampere]

Originally Posted by nejccesar

Is it possible to just remove the electric brake from the motor? See the attached pics of my motor. Should I just remove the silver bit? or somehow disable it?

I hope you aren't being serious! That motor does not have an "Electric Brake".

[InvalidUsername]

Originally Posted by nejccesar

Is it possible to just remove the electric brake from the motor? See the attached pics of my motor. Should I just remove the silver bit? or somehow disable it?

Electromagnetic brakes are on the wheels. That wouldn't have caused your problem.