AS 4070:1992 (R2015) PDF Download

The AS 4070:1992 (R2015) standard provides guidelines for the protection of electrical installations and equipment operating at nominal 240/415 V, 50 Hz in Multiple Earthed Neutral (MEN) systems. The standard aims to prevent damage caused by transient overvoltages exceeding 2500 V, which can arise from lightning discharges and switching events.

The standard does not cover the protection of installations from temporary overvoltages resulting from faults in the electricity supply system. It also does not apply to equipment connected to both electricity supply and information technology services, such as telephone cables and TV antennas. The standard emphasizes the importance of adopting a common earthing system to ensure the protection of all electrical services.

Furthermore, the standard notes that compliance with AUSTEL mandatory Technical Standard 001, which specifies requirements for overvoltage protective devices in equipment connected to telecommunication networks, should be considered. While for most applications of this standard, telecommunication networks may not need to be taken into account, if connections are made between systems or if both systems are enclosed in common ducts, both the AS 4070:1992 (R2015) and AUSTEL mandatory Technical Standard 001 should be met. It is also recommended to refer to AS 3260.