ELR72/ELR72V24 Electronic Residual Current Relay Technical Manual

This document provides technical specifications, connection diagrams, and programming instructions for the ABB ELR72 and ELR72V24 electronic residual current relays, compliant with IEC/EN 60947-2 Annex M. It details adjustable sensitivity (IΔn) and delay time settings via minidip switches, auxiliary power supply options, fail-safe and autoreset functions, and wiring for toroidal transformers and trip coils.