| Figure: Earth Leakage Relay |
Earth Leakage relays short ELR or also known as ground fault relays, are residual current monitors (RCMs) that are used in electrical wiring to detect potentially dangerous ground fault electrical hazards that may cause mechanical damage to cables and devices.
If fault currents become a significant value that is involved, hazardous voltages may also appear on earthed equipment, putting lives at risk.