This came up on another forum yesterday, caravan supply cables.

32 amp caravan supply cable that was 4mm flex on a caravan park which supplies an outlet to each pitch.

708, fig. 708 gives a drawing of the supply, Note 2, page 270 says "..for a higher current, the CSA must be chosen so that secure tripping of the over current protective device is achieved..."  But the note above says refer to 721.55.2.6

So, from that, a 4mm 3 core flex of 25 metres would be acceptable - Page 470, Table 4F3A, albeit, volt drop and R1 + R2 will need to be taken into account, but we are assuming the lead is short enough to satisfy those.(ICBA working that out now, but a rule of thumb says 25m will satisfy all requirements)

Then we have 721.55.2.6 ,and  Table 721, Minimum CSA of flexible cables for caravan connection, which, for 32 amp, says 6mm is required.

Why the confusion on this, between 708 and 721?  Surely they would be better as one chapter on their own, rather than separate chapters which need reference to each other?