Littelfuse EL500 Single-Function Earth Leakage Relays

Littelfuse EL500 Single-Function Earth Leakage Relays are designed to measure leakage current and isolate the faulty circuit from the system. Leakage currents are sensed through a core-balance current transformer (CBCT), and when the leakage current exceeds the set level, the device will trip. The trip level and trip time settings are adjustable with front-mounted potentiometers, and additional features include LED trip and power indication, LED bar graph indication for leakage current, remote test and reset, and CT OPEN indication. The EL500 relay offers dual operation modes, supporting fail-safe and non-fail-safe wiring to fit different safety standards. Suitable applications for EL500 relays from Littelfuse include industrial panels, commercial buildings, critical systems, hazardous areas, and residential safety.

Features

  • Wide protection relay
  • Compact design
  • Selectable thresholds and delays
  • Dual operation modes
  • LED trip and power indication
  • LED bar graph indication for leakage current
  • Front-panel and remote test/reset
  • CT OPEN indication

Applications

  • Industrial panels
    • Motors
    • Transformers
    • Switchboards
  • Hazardous areas
    • Refineries
    • Chemical plants
  • Shock prevention at main distribution
  • Commercial buildings
    • Distribution panels
    • Insulation fault detection
  • Critical systems
    • Hospitals
    • Data centers
    • Control rooms

Specifications

  • 30mA to 30A selectable earth leakage current
  • 0 to 10s configurable trip time
  • 110VAC to 240VAC auxiliary supply range
  • Base or DIN-rail mounting
  • One changeover (Form C) and one NO (Form A) relay output
  • ±20% supply variation
  • 5V maximum power consumption
  • -15°C to +60°C operating temperature range
  • 36mm x 90mm x 66.2mm dimensions

Simplified Circuit Diagrams

Mechanical Drawing - Littelfuse EL500 Single-Function Earth Leakage Relays
Inilathala: 2025-09-29 | Na-update: 2025-10-15