New Sigma-L protection line
IFX4L – Digital overcurrent and ground fault multifunction relay
The multifunction protection relay IFX4L belongs to SIGMAL digital protection line and it performs functions as phase overcurrent and earth fault relay.
IFX4L relay is compliant with Italian document Norma CEI 0-16 in reference to “general protections” and is equipped with internal Logger.
The user can select the operating modes and auxiliary functions listed in the table below:
FUNCTIONS | ANSI |
Two-phase overcurrent | 50 51 |
Three-phase overcurrent | 50 51 |
Two-phase overcurrent + earth-fault | 5051 50N 51N |
Three-phase overcurrent + earth-fault | 5051 50N 51N |
Earth-fault overcurrent (non directional) | 50N 51N |
Stator earth-fault (95%) | 64S |
Transformer case earth-fault | 64T |
2nd harmonic restraint | 50BF |
Cold Load Pickup | |
Breaker failure | |
Circuit breaker monitoring |
All the functions of the relay are fully programmable by front panel keyboard or through a RS485 serial interface using a personal computer with set-up program; furthermore the relay can be programmed through a remote control and monitoring system.

