Main breaker trip

[Todd0x1]

One circuit was just laying on the floor, and I wanted to find out what was on it. I dead-shorted it (in such a way that it didn't arc), and it tripped a single pole 20 amp breaker in a subpanel as well as the 100 amp breaker which feeds that subpanel.

That's a good way to start a fire. Please buy yourself one of these, there's an accessory kit that gets you alligator clip leads

Digital Circuit Breaker Finder with GFCI Outlet Tester - ET310 | Klein Tools

The Klein Tools ET310 Circuit Breaker Finder with Integrated GFCI Outlet Tester is a digital circuit breaker finder used to locate the correct circuit breaker in a panel to which an electrical outlet or fixture is connected. The Transmitter is connected to the electrical outlet or fixture in the...

www.kleintools.com

 

[James L]

That's a good way to start a fire. Please buy yourself one of these, there's an accessory kit that gets you alligator clip leads

Digital Circuit Breaker Finder with GFCI Outlet Tester - ET310 | Klein Tools

The Klein Tools ET310 Circuit Breaker Finder with Integrated GFCI Outlet Tester is a digital circuit breaker finder used to locate the correct circuit breaker in a panel to which an electrical outlet or fixture is connected. The Transmitter is connected to the electrical outlet or fixture in the...

www.kleintools.com

There isn't any way a soft trip will start a fire.
I have one of those circuit finders, though. Hard to plug it in to the end of a bare romex. I don't have alligator clips

 

[Todd0x1]

There isn't any way a soft trip will start a fire.

It can happen. Bad connection between the breaker and you, the wires stick together when you touch them, circuit impedance such that current is limited below instant trip range so breaker doesn't trip right away. Had it happen unintentionally once where a wire welded itself to a box. Took many seconds for breaker to trip, thing was glowing.

 

[jaggedben]

The person who came before me had it energized already. It ended up being a home run connected to nothing, just laying on the floor

Yup, I get it, same thing happened to me. I trust you won't do that. It still boggles my mind that people do this sort of thing.