TDG Aerospace

UFI® Fault Prevention

UFI® Universal Fault Interrupter

UFI® is a patented, derivative technology from TDG Aerospace's successful NOFOD® wing ice prevention system. TDG's UFI® products are specifically designed to monitor and protect AC & DC circuits from dangerous electrical fault conditions.  While UFI® technology is currently employed on a variety of commercial aircraft, it is also well-suited for military, marine or commercial applications where electrical system health and safety is paramount.


By independently monitoring the current and voltage on each phase of AC power, UFI® technology provides unprecedented insight into the real-time health and operational status of a given three-phase electrical circuit. Where there is an increased sensitivity to catastrophic failure conditions (fuel pump circuits) or financial incentive to avoid     operation-to-failure, the benefits of UFI® technology are many.


UFI® technology is readily adaptable to single phase AC or DC circuits.

Transient Electrical Fault Detection Steady State Fault Detection
Line-to-ground current (parallel fault) Unbalanced phase currents    
Line-to-line current (parallel fault) Out-of-range phase currents    
Open phase (series fault) Out-of-range phase voltages

The above fault conditions are detected based upon programmable thresholds that are set during unit manufacture, making the UFI® device infinitely adaptable to a given load and application.

Non-Volatile Memory

UFI® devices constantly record operational information into non-volatile memory, which can then be downloaded by maintenance technicians for assistance in preventative maintenance (end of life cycle prediction) or troubleshooting.

Leading Edge Technology

All UFI® devices have an all solid-state design with a predicted MTBF > 100,000 hours, and are designed to DO-160 Hardware Assurance Level B and DO-178 Software Assurance Level B.

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