17th edition iee wiring regulations explained and illustrated eighth edition pdf

It must be remembered that the Regulations are not a collection
of unrelated statements each to be interpreted in isolation; there
are many cross-references throughout which may render such an
interpretation valueless.

In using the Regulations I have found the index an invaluable
starting place when seeking information. However, one may have
to try different combinations of wording in order to locate a particular item. For example, determining how often an RCD should be tested via its test button could prove difficult since no reference is made under ‘Residual current devices ’ or ‘Testing ’; however,
‘Periodic testing ’ leads to Regulation 514.12, and the information
in question is found in 514.12.2. In the index, this Regulation is
referred under ‘Notices