That'll be because it's written for NICEIC members.?I have a copy of that great book but I do think some of their recommendations assume a lack of “electrical common sense”.
I'm not supposed to find that funny let alone in some cases agree
The sample of an NIC MWC in my post above may not be that clear but there are boxesWhere do you record the measurement, and in the case of an RCBO the operating time?