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Maximum disconnection times for Uo 230V.

SYSTEM FINAL CIRCUITS DISCONNECTION TIMES
(Circuits not exceeding 32A)
FINAL CIRCUITS DISCONNECTION TIMES (Circuits exceeding 32A) and DISTRIBUTION CIRCUITS (Regardless of size)
TN a.c. 0.4 5
     
TT a.c. 0.2 1









 

 



Note - where in a TT system, disconnection is acheived by an overcurrent protective device and protective equipotential bonding is connected to all the extraneous-conductive parts within the installation in accordance with regulation 411.3.1.2, the maximum disconnection times applicable to a TN system may be used.