On 2011-10-03, Wes wrote:
Ignoramus19762 wrote:

OSHA has gotten religion on the arc flash issue. The #1 chance
for such that will kill folks is when you close a large
main/sub-main breaker. They can and do explode outward with
enough force to blow apart cabinets, taking out the chump
standing there closing the breaker.

So, why exactly do they explode? Can you explain?

I can't but I stand to the side of control panel boxes when turning
on the main disconnect. One time seeing a Hoffman box open from the
arc flash was enough for me. No, I didn't do the work, I was a by
stander.

Scary.

Can this happen with 240v 3 phase?

My building has only 240v. 800 amps service.

i