- Circuit breakers are electrical switches that automatically turn off electrical flow when a problem with the circuit is detected. Electrical flow is constantly monitored, and when an overload or short circuit is detected, the circuit breaker breaks the flow of electric current.
- In areas in which earth impedance is high, there is a risk of shock. Earth impedance tends to be high in areas where there is a local grounding (earth) rod or when soil conditions are dry. In areas that earth impedance is high, the risk exists because the current that flows will not be enough to trip the circuit breaker. This allows the current to remain, which poses a continued risk for shock. In addition, the high impedance earth does not have the ability to ensure that exposed metal voltage remains at a save level. Areas with high impedance earth, and no additional protection, offer considerable risk for electrical injury.
- Earth Leakage Circuit Breakers and Residual Current Devices are safety devices that offer that additional protection. These two types of safety devices are used in areas that have high levels of earth impedance. These devices have the primary purpose of reducing the risk of shock in the event of a current flow to the earth.
- Electric current charges that are not strong enough to trip a regular circuit breaker are still enough to injure or even kill a human. These charges can lie in wait in a piece of metal equipment, without the protection offered by more sensitive circuit breakers. Earth Leakage Circuit Breakers are sensitive enough to detect even tiny amounts of current present in faulty metal electrical equipment.
- Earth Leakage Circuit Breakers are slightly less sensitive than Residual Current Devices, although the two share the same function. For this reason, an Earth Leakage Circuit Breaker is less likely to cause false alarms.
