Earthing design and integration - Principles

The railway environment presents a number of different challenges to be addressed when designing an earthing system: the need to ensure personal safety, the correct operation of electrical protection systems, the requirement to minimise harmonic noise in the earthing system and the requirement to provide surge protection are a few of the issues to be considered whilst also ensuring the correct operation of the equipment connected to it. The integration of different and occasionally conflicting requirements is the key to designing an operational earthing system in a railway environment; ensuring that each earthing system operates correctly and safely when integrated with others.