SS 638:2018

Code of practice for electrical installations


Applies to the design, erection and verification of electrical installations other than those specifically excluded under its scope.

Includes requirements for:

(i) circuits supplied at nominal voltages up to and including 1000 V a.c. or 1500 V d.c. For a.c., the preferred frequency which is taken into account in this Code is 50 Hz;
(ii) circuits, other than the internal wiring of equipment, operating at voltages exceeding 1000 V and derived from an installation having a voltage not exceeding 1000 V a.c., e.g. discharge lighting, electrostatic precipitators;
(iii) wiring systems and cables not specifically covered by the standards for appliances;
(iv) all consumer installations external to buildings;
(v) fixed wiring for information and communication technology, signalling, control and the like (excluding internal wiring of equipment);
(vi) additions and alterations to installations and also parts of the existing installation affected by an addition or alteration.

Does not apply to installations such as systems for the distribution of electricity to the public, equipment of motor vehicles, mobile and fixed offshore installations, aircraft or on board ships, radio interference suppression equipment (except so far as it affects safety of the electrical installation), lightning protection systems for buildings.




Status Current
Edition 2018
No. of Pages 452
ICS Classification 29.020 Electrical engineering in general
91.140.50 Electricity supply systems
Committee Electrical and Electronic Standards Committee
Available for Purchase For sale in Singapore only
Adoption BS 7671+A1-A3 : 2008 MOD