详细介绍：

The NPI 800 relay protects three-phase electrical networks
against all types of phase to earth and phase to phase faults.
In addition, the NPID 800 features a directional function.

ANSI FUNCTIONS FOR NPI 800 :
50 / 51 / 50N / 51N / 46 / 46BC / 49 / 50BF / 74TC / 86

ANSI FUNCTIONS FOR NPID 800 :
50 / 51 / 50N / 51N / 67 / 67N / 46 / 46BC / 49 / 50BF / 74TC / 86