Earth Leakage Relays

General Details

Earth Leakage Relays offered in the 373-ELR series are residual current devices used to detect potentially dangerous earth fault currents before damage is caused. An undetected fault current may lead to cables overheating, which could start a fire. If high fault currents are involved, hazardous voltages may also appear on earthed equipment, putting lives at risk.

Earth Leakage Relays allow the fault current to be continuously monitored and compared with the user selectable leakage level. Should the leakage exceed this level, the relay will trip to indicate a fault condition. With a very fast response time of under 40ms, the supply can be disconnected before serious damage can occur.

This product is intended to provide a high degree of earth leakage protection and monitoring for any electrical equipment, specifically motors and their control gear, generator sets and transformers.


  • 0-1mA analogue output
  • 8 amp 250V rated relay contacts
  • 10 selectable trip levels – 30mA to 10A
  • 16 selectable time delay – 0ms to 10 seconds
  • Double-pole change over relay
  • LED bar graph display
  • Less than 40ms response time
  • Precision digital settings
  • Single-pole pre-alarm option
  • User selectable energize or de-energize link


  • Advanced warning of faults
  • Complementary range of core balanced CTs
  • Detects residual current flow
  • DIN-rail 43880 enclosure
  • Insulation monitoring
  • Isolation of faulty circuits
  • Protection of expensive power assets
  • Switched mode supply accepts a wide range of auxiliary voltages


  • Building management
  • Control panels
  • Distribution systems
  • Generator sets
  • Motor protection
  • Process control
  • Switchgear
  • Transformer protection
  • Utility power monitoring


  • CE
  • CE