Littelfuse, Inc. EL731 Series – Earth-Leakage, Ground-Fault Relay EL731-20-00

The EL731 series is a microprocessor-based AC/DC sensitive earth-leakage relay designed for low-level ground-fault protection in variable-speed drives and DC circuits. It features a 32-character OLED display, three programmable Form C output contacts, adjustable trip and alarm settings from 30 to 5,000 mA, trip delays from 0.05 to 2 seconds, and an RTD/PTC sensor input for motor temperature monitoring. The relay operates with a 24 Vdc power supply, supports frequency detection from 0 to 6,000 Hz with optional CT configurations, and includes analog output (4-20 mA), CT-loop monitoring, and harmonic filtering. It has a conformal coating and mounts via panel, surface, or DIN rail with optional adapter. Dimensions are 48 mm H × 96 mm W × 129 mm D. Approvals include UL Listed, CSA, RCM, and CE.