The Omega is an Earth Fault relay with a dual indicator – red LED and flag that can be operated from from a Bowdens Band CT or a  conventional cast resin core balance CT. It has user settable trip current, and trip duration settings, as well as a reset time range of  between 3 and 12 hours. It can be powered by a replaceable long life lithium battery giving a 15 year average life under normal operating conditions or it can be powered from the incoming LV mains, in which case the option for LV supply reset is available. The indicator is driven by high capacity super caps  whilst the LV supply is absent. This means that no batteries are required with the LV unit. The OMEGA III EFI has a high intensity red LED indicator as well as a black/red flag disc and the facility for a remote LED indicator external to the substation. It has two alarm output relays with either latching or fleeting function. OMEGA III may also be powered and reset from an RTU supply. It also has manual controls for Test and Reset.


  • Earth Fault Indicator with twin LED and flag local indication
  • Remote LED indicator can be used outside the substation
  • User selectable for trip current 20 to 200 Amps, and fault duration 20msecs to 200msecs
  • User selectable timed reset 3 to 12 hours
  • Powered from 15 year lithium battery or LV mains with super capacitors to power unit during fault duration
  • LV Reset available when powered from LV
  • Two Alarm output relay – changeover Volts free with Latching or fleeting options
  • Push button Test & Reset
  • Band sensor CT or Cast Resin CT
  • ‚ÄčNo battery required for the LV version