[DonRotolo]

Think about the heat required to melt copper - those 'pearls' on the end of some strands were formed by heat.

That heat came not form contact resistance, but from arcing. An arc is electricity forming a plasma, reaching temperatures of several thousand degrees (often around 10k) in a split second. This is how many home fires start, because the plasma is not a dead short (which would trip a breaker) but a 'high resistance short' usually permitting around 15-18 Amps at 12 VDC. For homes, you can now buy an "arc-fault' circuit breaker, which detects the characteristic high-frequencies of an arc and cuts the power.

Glad the robot didn't catch fire.

Don