On 4/11/2013 11:02 PM, Dwain Swick wrote:
I always built my conversions with a solenoid connecting power from the controller to the motor and the throttle controlling the solenoid. When the throttle was off the power was off. If you reversed with your foot in the throttle, then you deserved what you get. Where is common sense and safety?
To be fair, there are sometimes reasons to switch rapidly between forward and reverse. When you're stuck in snow for example, you may need to "rock" the car forward and backward every second or so to it unstuck.
Warning: a quirk of series DC motors is that you do not want it rotating slowly in the wrong direction when you apply power. When rotated backwards from the direction it wants to run as a motor, it becomes a series generator. Unless your controller is set up for regen, it can't control the generated current. The motor can generate a huge current, to murder the freewheel diodes in the controller, or break something in the drive train.
-- The principal defect in a storage battery is its modesty. It does not spark, creak, groan, nor slow down under overload. It does not rotate. It works where it is, and will silently work up to the point of destruction without making any audible or visible signs of distress. -- Electrical Review, 1902 -- Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
