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@Inteificio you have actually pin pointed (or stumbled onto?!) one of the interesting areas where the regs alone don't completely answer the question.
It reminded me of an interesting thread on another forum from years ago which I've attempted to link to.
Plugging 800A fault current into the adiabatic with 0.1s disconnection time (the lowest the regs give us) gives a concerning answer, as you identified I think. But you need to read the bit in the box on the graph that says for larger PFCs use manufacturers data.
As above, we need a bit more info from the manufacturer to be reassured that the device will actually operate quicker than 0.1 s.
Manufactures will list a "Rated short circuit breaking capacity", i.e. it will cope with the fault current. At least 6kA usually.
And the manufacturers graphs usually go a lot lower than 0.1s. e.g. this Hager B16:
Plugging 800A into the adiabatic with 0.01s gives you a much more reassuring answer.
Hope that helps.
It reminded me of an interesting thread on another forum from years ago which I've attempted to link to.
IET EngX
tinyurl.com
Plugging 800A fault current into the adiabatic with 0.1s disconnection time (the lowest the regs give us) gives a concerning answer, as you identified I think. But you need to read the bit in the box on the graph that says for larger PFCs use manufacturers data.
As above, we need a bit more info from the manufacturer to be reassured that the device will actually operate quicker than 0.1 s.
Manufactures will list a "Rated short circuit breaking capacity", i.e. it will cope with the fault current. At least 6kA usually.
And the manufacturers graphs usually go a lot lower than 0.1s. e.g. this Hager B16:
Plugging 800A into the adiabatic with 0.01s gives you a much more reassuring answer.
Hope that helps.