Quote:
Originally posted by Al Skierkiewicz
Andrew,
When you say "short through the case" what do you mean? Did you have motor wiring accidentally shorted to the robot frame? If that is the case and you had the motors running in opposite directions I can see how that resulted in the failure. Did the Victor that failed have shorter power wiring feeding it than the one that survived?
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This was a flukey short, but here's what it was.
One drill motor had a short between its motor terminal and our aluminum heat sink shroud which surrounded it. This shroud was mechanically (and electrically of course) connected to our aluminum frame.
On the second drill motor, we had a short between the ring connector and the mounting screw for the speed controller. The mounting screw was mechanically and electrically connected to to the same case, although on the opposite side of the robot. (Note: we now use plastic 6-32s to mount our speed controllers to the frame).
I'm not sure whether we had M+ on one motor connected to M- on the other (in which case forward would have been bad) or whether we had M+ connected to M+ (in which case opposite would have been bad).
I'm sure the length of wiring was different, but not by much. I just assume that the weakest component started to flame out first.
Andrew, Team 356