I am looking to size several fuses' breaking capacities on a battery circuit.
Let's consider F1 = 300 A; F2 = 20 A; F3 = 40 A.
Given the battery is high-power and can output several kAs, the main fuse (F1) has a breaking capacity in the dozens of kA.
F2 & F3 feed off the main fuse and protect some smaller loads (20-40 A).
From similar designs, accessory fuses always are of a much smaller size and breaking capacity, however I don't see how a short-circuit on these circuits wouldn't warrant the same fault current and in turn turn F2 & F3 into plasma balls before the main fuse has the chance to pop.
Ther must be a flaw in my reasoning but I've yet to see it.
simulate this circuit – Schematic created using CircuitLab
kAs? ... kilo amp seconds? \$\endgroup\$