17th Wiring Regulations Explained and Illustrated

It was once said, by whom I have no idea, that ‘rules and regulations

are for the guidance of wise men and the blind obedience

of fools ’. This is certainly true in the case of the IEE Wiring

(BS 7671) Regulations. They are not statutory rules, but recommendations

for the safe selection and erection of wiring installations.

Earlier editions were treated as an ‘electrician ’s Bible ’: the

Regulations now take the form primarily of a design document.

The IEE Wiring Regulations are divided into seven parts. These

follow a logical pattern from the basic requirements to inspection

and testing of an installation and finally to the requirements for

special locations:

Part 1 indicates the range and type of installations covered by the

Regulations, what they are intended for, and the basic requirements

for safety.

Part 2 is devoted to the definitions of the terms used throughout

the Regulations.

Part 3 details the general information needed and the fundamental

principles to be adopted before any design work can usefully proceed.

Part 4 informs the designer of the different methods available for

protection against electric shock, overcurrent, etc., and how to

apply those methods.

Part 5 enables the correct type of equipment, cable, accessory, etc.

to be selected and erected in accordance with the requirements of

Parts 1–4.