Type ELR-D2V and ELR-3AN complete the range of type A earth leakage relays with external toroid, designed for detecting alternating and pulsed DC fault currents. These relays are suitable for protecting electrical systems and circuits in residential, commercial, and industrial environments, where electronic devices may generate non-linear fault currents. These relays feature a built-in display for the setting of the intervention and pre-alarm thresholds, and the viewing of the differential current, indicated by three backlight colors: green in case of normal operation, yellow for pre-alarm threshold exceeded, and red in case of fault current intervention.

Both the relays are powered by 230VAC auxiliary voltage and include front LEDs to signal the presence of power supply and relay status indication, as well as TEST and RESET buttons for relay testing and manual reset after intervention.

They mainly differ in the number of integrated relay outputs and the dimensions: the ELR-D2V type integrates one relay output for intervention signaling and is housed in a compact 2-module enclosure, while the ELR-3AN type integrates two independent relay outputs (for intervention and pre-alarm signaling) in a 3-module enclosure.

ELR-3AN also offers additional functionalities, including two digital inputs for remote command of the TEST and RESET functions as an alternative to the front buttons, and an adjustable third or twenty-first harmonic filter to enhance intervention accuracy, ensuring correct measurement of leakage currents even in electrical installations subject to harmonic disturbances, avoiding false alarms, and improving the overall system reliability and safety.