- Reaction score
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Needs to disconnect in 0.4 of a second does it not for TN systems.I wasn't aware that there is a required disconnection time for short circuit.
If your disconnection times are met for earth faults then it’s not a requirement to calculate or measure short circuit as the likelihood is this will be satisfied if your zs times are met, however if you cannot meet your earth fault loop impedance times though a protective device like an mcb and rely on the rcd for the earth faults only then short circuit times still need to be met don’t they?
No good having a live to neutral fault and taking 10 seconds for example to disconnect is it?