Diconnection times

[malcolmchisholm]

Table 41.1 in 17th Ed book refers to this.

I have been told that if a final cct is off a sub-main board then the disconnection time is 5 sec. Is this true? I cannot find any reference to this.

 

[brucelee]

no mate only if its a distribution circuit 5 secs for tn and 1 sec for tt
final circuits are 0.4 for 32a and under and 5secs for over 32a in tn systems
and final in tt are 0.2secs under 32a and are 1 sec for over 32a in tt sytems like mac said
this is what we was taught in 2391