what is earth leakage

Earth leakage is electric current that finds its way to earth via an unintended path. There are two categories of earth leakage: unintentional earth leakage, which results from faulty insulation or equipment, and intentional earth leakage, which is a consequence of the way equipment is designed. Earth leakage can cause electric shocks, so it must be prevented. This is usually done by using either RCDs (residual current devices) or RCBOs (residual current circuit breakers with overcurrent protection) . Earth leakage can exist through an insulation fault in cables or equipment, or it can occur under normal operating conditions in electronic equipment which use capacitors for filtering purposes in power supplies which can cause leakage to Earth when functioning. Leakage current is also defined as ‘electric current in an unwanted conductive path under normal operating conditions’ . Earth leakage current can be measured using a leakage current clamp ammeter.