F50/51, F50N/51N, F51BF, F68
Programmable three phase over current with time curve and earth leakage relay expedients to MV&;HV energy transmission and distribution systems.
Its phase and neutral current inlets can be selected as 1 A or 5A.
Inlet circuit of neutral current has got an active filter which percolates the 3. Harmonic.
There are two programs which can be selected by digital input or serial port.