Regen braking fried my controller

[InvalidUsername]

Originally Posted by 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.

You can adjust the regen braking current to whatever you want, from 0 to full motor current, from nothing to one-pedal driving

[InvalidUsername]

This is what you can program in a 1266. Remove .txt from end of filename if you want to view as spreadsheet

1266 parameters original.XLS.txt

[InvalidUsername]

Originally Posted by InvalidUsername

You can adjust the regen braking current to whatever you want, from 0 to full motor current, from nothing to one-pedal driving

Oops I take that back. Looks like 50A is the minimum

[nejccesar]

Sorry I am a big noob when it comes to golf carts :D So the brakes are generating electricity when going downhill? Can I unplug those, as the mechanic part worked fine after the controller fried.

[kgsc]

The motor itself acts like an electric brake essentially charging the pack back through the controller. It’s called regeneration.

[nejccesar]

Originally Posted by InvalidUsername

You can adjust the regen braking current to whatever you want, from 0 to full motor current, from nothing to one-pedal driving

If I turn off regen braking through software, will the motor still generate electricity going downhill? Could that fry the controller, or the motor will not generate electricity because the regen braking will be off?

[InvalidUsername]

Originally Posted by nejccesar

If I turn off regen braking through software, will the motor still generate electricity going downhill? Could that fry the controller, or the motor will not generate electricity because the regen braking will be off?

No. The controller uses the rotation of the motor to generate electricity rather than consume it by reversing armature/rotor current. The cart just coasts if regen is off. When it's on you can feel it slowing down the cart (of course this varies based on the programmed strength). Did you ever feel a resistance when going down the steep hill instead of gaining speed? It feels dangerous to me to go down a steep hill in a golf cart relying on just the mechanical brakes because it doesn't provide good control. Regen is like downshifting in a car when going downhill to use the motor as a brake to better control the descent.

[nejccesar]

Originally Posted by InvalidUsername

No. The controller uses the rotation of the motor to generate electricity rather than consume it by reversing armature/rotor current. The cart just coasts if regen is off. When it's on you can feel it slowing down the cart (of course this varies based on the programmed strength). Did you ever feel a resistance when going down the steep hill instead of gaining speed? It feels dangerous to me to go down a steep hill in a golf cart relying on just the mechanical brakes because it doesn't provide good control. Regen is like downshifting in a car when going downhill to use the motor as a brake to better control the descent.

Well yeah, I did feel the regen braking kicking in. I changed from AGM batteries to Lifepo4, when I changed them it worked ok the first day when the Lifepo4 batteries were at 50% charged, I went downhill and up no problems with regen braking. The next day I charged the lifepo4 batteries to full charge, wen downhill and the controller fried.
Before when I had the AGM batteries going downhill sometimes generated 75V of electricity from the motor, looks like the BMS did not accept the voltage now and it stopped in controller.

I am now afraid If i purchase the 1266 controller it will fry it again if I still use regen braking. The hill is 15% incline so it is pretty steep.

[Volt_Ampere]

I would recommend you don't charge to 100% if you plan to go down a steep hill after charging. I would go with an aftermarket controller like Alltrax. You can dial how much Regen you have with that. Also, you need a flyback diode to protect the controller if the BMS shuts the battery down while you are doing Regen braking. The diode handles the current and prevents a big voltage spike. The Alltrax diagram shows this diode for most carts.

[InvalidUsername]

Originally Posted by nejccesar

Well yeah, I did feel the regen braking kicking in. I changed from AGM batteries to Lifepo4, when I changed them it worked ok the first day when the Lifepo4 batteries were at 50% charged, I went downhill and up no problems with regen braking. The next day I charged the lifepo4 batteries to full charge, wen downhill and the controller fried.
Before when I had the AGM batteries going downhill sometimes generated 75V of electricity from the motor, looks like the BMS did not accept the voltage now and it stopped in controller.

I am now afraid If i purchase the 1266 controller it will fry it again if I still use regen braking. The hill is 15% incline so it is pretty steep.

Just don't go down the hill immediately after you've charged to 100% and you should be fine. Drive around for bit to use up some amp-hours (Ah). Getting a meter that shows battery capacity in a digital format is very helpful in that regard. Shunt meters are the best because they record the amps going in and out and give you a reading of Ah remaining.

Regen is a function of throttle percentage and speed. As you go down a hill the speed increases with the same throttle percentage, so when a certain mapping threshold is reached regen will kick in, and will increase as there's less throttle and more speed. Using the foot brake while you keep your foot on the throttle will help minimize regen.

Plus if you make a programming cable you can dial regen way down