What all does everyone use for controllers? In my car #59, I use an Alltrax AXE 4834P controller. Its great to program it to put out different voltages, amps, and throttle types too.

We started out with an Altrax controller but it kept shutting off once the voltage got to around 22 volts, resetting, etc. Got annoyed with it as it kept me from driving the last five mins at Corvallis issue free.

If its and AXE model, change the low voltage to its lowest setting if its a 48 volt controller. The lowest I can get on mine is 16 volts. On the 24 volt version ones however, the lowest voltage can get down to 6 volts, so put the scroll bar to its highest or set it at 16 volts. Thats probably what is going on, and to make sure its working right when programing, make sure the reset button is pressed. Otherwise it will not work at all. This happened to me last year at the Kilowatt Klassic in Eugene. Mike Hodgert said I looked like I was going to take a sledge hammer to my car. :P

We built our own microcontoller based speed controller. It's operated by a push button with the current limit being set by a potentiometer on the dashboard, the sort of racing we have in Greenpower means you rarely lift off the power so no need to give the driver a throttle control. An acceleration curve is programmed in which gives a soft start then a few seconds of over-current before returning to the selected current limit, this allows the car to accelerate at a decent rate without drawing too much from the batteries. The biggest advantage of building our own was cost, about £30 whereas a ready built controller is over £100 and would still require interfacing to a power management system.