To carry that further, to an extreme that lucklily is only occasionally required, very large breakers are designed to spit hot gas and molten metal in certain directions when it all goes wrong. (the good ol' I2 t, (or joules per ohm if you prefer an easier unit), have to go somewhere, ideally away from the switchgear operator!!) The correct enclosure is essential to making this happen safely - large cabinets have part cut sheet flaps at the back or the top that bend outwards like louvres in a controlled way to spread the explosive shock out over a longer time, and for things like a substation next to a building, the outer containment may be carefully designed to blow out one wall or a take off a light roof, without affecting the remaining structure.
The 'rating' for such a system is complex, and depends how much needs to be "reset" (or rebuilt) before it can be switched on again.
To carry that further, to an extreme that lucklily is only occasionally required, very large breakers are designed to spit hot gas and molten metal in certain directions when it all goes wrong. (the good ol' I2 t, (or joules per ohm if you prefer an easier unit), have to go somewhere, ideally away from the switchgear operator!!) The correct enclosure is essential to making this happen safely - large cabinets have part cut sheet flaps at the back or the top that bend outwards like louvres in a controlled way to spread the explosive shock out over a longer time, and for things like a substation next to a building, the outer containment may be carefully designed to blow out one wall or a take off a light roof, without affecting the remaining structure.
The 'rating' for such a system is complex, and depends how much needs to be "reset" (or rebuilt) before it can be switched on again.
