Ground Fault Interrupt (GFI)

Product Information

FAA safety regulation SFAR 88 requires transport-category aircraft manufacturers to modify fuel systems to eliminate the possibility of an ignition source developing within a fuel tank.

Boeing has selected Leach International as the exclusive provider of Fault Current Detection (FCD) and Ground Fault Interrupt (GFI) relays to satisfy SFAR 88. Our GFI relays sense fuel pump ground faults, while our FCD relays  sense fuel pump ground faults and phase-to-phase shorts in the fuel pump and up-stream wiring. Through the use of a proprietary electronic circuit design, Leach International GFI and FCD relays will detect these faults and open the circuit within milliseconds, thereby minimizing the potential of fuel-system combustion. Leach International GFI relays have been selected for retrofit as well as for new production of 727, 737, 747, 757, 767, and 777 aircraft and FCD relays to retrofit all DC-10, MD-10 and MD-11 aircraft.


 “Ground Fault Protection” from Avionics Magazine . featuring the Leach International GFI solution

Technical Papers

 Ground Fault Protection
 Arc Fault Detector


 Aircraft Ground Fault Detection & Isolation

This site uses cookies to help deliver an engaging user experience.
To learn more about what cookies are and how to manage them visit