SLU-70 Lugs

[Al Skierkiewicz]

Originally Posted by eugenebrooks

The rating of 6 gauge wire varies, depending upon the application.
For open chassis wiring 6 gauge wire is listed at 101 amps
http://www.powerstream.com/Wire_Size.htm
and this rating is referred to as conservative.
The robot construction guidelines document, Guidelines_c.pdf, listed
6 feet of 6 gauge wire as carrying 125 amps, based on a 2.5 % voltage
drop for 12 volts. The power dissapated in by the wire in this instance
is 37.5 watts, about a half watt per inch. It is going to get warm, and
you don't want to be giving away .3 volts like that, but it is safe for short
durations in the open air.

One of the things that was refreshing in the 2005 electrical rules
was the reasonable limits for allowed current in the wiring, making
for a lighter robot.

I agree with Gene on the wire rating. In many cases the wire gauge tables are set for max voltage drops in normal runs (volts/ft at some current) and allowing a safe temperature rise in the wire based on insulation. (ratings differ between open air and in conduit and there is a derating factor as you add more conductors in the same conduit.) Add to that the tables for the 120 amp breaker and over current of as much as 600% for a few seconds and the wire is safe for our use when currents go above 120 amps in a two minute match.

I do not agree on the wire rules allowing #12 and #14 as I think it allows teams to shoot themselves in the foot. In thinking the lighter wire is good for weight when all it does is limit the current supplied to critical motors. I still recommend #10 be used on most motors, not a rule, just a suggestion.