SPI Range

The SPi range of fault passage indicators is designed for application to distribution networks where manually operated or automated switchgear is installed. When current above a threshold level is detected, the indicator operates alarm contacts for remote indication and illuminates an integral high brightness Light Emitting Diode (LED). Indicators strategically placed in the distribution network aid identification of a faulty section.


The SPi-EF (Self Powered Earth Fault Indicator) and SPi-OCEF (Self Powered Over Current & Earth Fault Indicator) detect the passage of earth fault current at a point on an underground High-Voltage (HV) cable distribution network. Fault current is detected using a core balanced or phase mounted CT. Indication is by a flashing LED and electrical output contacts. The device does not require a battery.


  • Locate faults on overhead High/Medium-Voltage (HV/MV) networks quicker
  • Restore customers electricity supplies faster
  • Flashing Xenon beacon and LED with timed self-reset/ voltage reset option
  • Self-powered with 10 year life Lithium battery, no need to recharge
  • Telecontrol output contacts
  • Differentiate between Permanent (damage) and Transient faults
  • Rugged design suitable for outdoor use


SPi-OCEF Programmable

The SPi-OCEF programmable detects and indicates the passage of phase fault, earth fault and SEF currents. Designed for use with remotely controlled and automated HV/MV switchgear it is connected to 3 phase CTs and can be used on both overhead and underground cable networks.


  • Designed for use with HV/MV distribution automation schemes
  • Locate faults on underground HV/MV cable networks quicker
  • Suitable for use with pole top and ground mounted switchgear
  • Supplied ready for DIN rail mounting
  • Separate CT termination block for safety
  • Intelligent LED and volt free indications and reset