Glossary
Protective earth
What is Protective earth?
The green-and-yellow conductor that connects touchable metal parts of the AC system to earth potential. In the event of a fault, the current that trips the protective device flows through it.
What matters about Protective earth in practice?
It is run continuously, never switched, never fused and never interrupted. An interrupted protective earth cannot be seen from the outside — the system runs normally until the first fault.
At the berth, it also connects the underwater fittings of all connected boats. Disconnecting it for that reason solves a corrosion problem and creates a life-threatening one. The right way is a galvanic isolator or an isolation transformer.
Related terms
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