Sorry, I didn’t have time to finish my previous post correctly.
According to IEC, the protective device of a low-voltage feeder must provide two basic protections:
P1. the protection of people against indirect contact (obtained by a specified disconnection time of an overcurrent cut-out...
To 7anoter4
IEC 60364-5-52 contains tables of cable current ratings, with corresponding conductor temperature, ambient temperature and soil temperature + various derating factors.
There is a website where data on LV cables is collected (from IEC 60364-5-52, BS 7671, NF C 15-100 and AS/NZS)...
The choice of cables and protective devices for them is a complex procedure, and in fact, to select cable cross-sections + circuit breaker correctly, you must calculate not only actual load current but also the short-circuit currents in two points: at the end terminals of the protective device...
