jaggedben
Senior Member
- Location
- Northern California
- Occupation
- Solar and Energy Storage Installer
As we all know, hot can touch ground or grounded metal, spark, melt metal, and sometimes not trip the breaker.
Agreed. The short has to be low impedance, and last long enough to raise the temperature of the breaker. Often momentary contact doesn't do this, and arc flash interrupts the contact before the breaker heats up.
I may be wrong but it seems to happen more often the longer the run back to the breaker, is it possible that resistance of wire affects breaker tripping?
It is possible, because as resistance is greater current becomes less. This is basic theory, Ohms law, V=IR. On the other hand, the resistance of copper wire is low enough that the length of run should have only a marginal effect on whether a breaker trips, except for very long runs.