11SIPROTEC 7SJ81/7SK81 V4.70, Product Information
E50417-K1150-C462-A2, Edition 02.2012
The SIPROTEC devices 7SJ81 and 7SK81 feature protection functions
similar to the 7SJ80 and 7SK80 devices, which are described in the
following table.
Package Function 7SJ81 7SK81
Basic func-
tionality
50/51 Time overcurrent protection phase
50-1, 50-2, 50-3, 51
XX
50N/51N Time overcurrent protection ground
50N-1, 50N-2, 50N-3, 51N
XX
50N(s)/51N(s) Sensitive ground fault protection
50Ns-1, 50Ns-2, 51Ns
XX
49 Overload protection XX
74TC Trip circuit supervision XX
50BF Circuit-breaker failure protection XX
46 Negative-sequence protection XX
37 Undercurrent monitoring XX
86 Lockout XX
Parameter changeover XX
Monitoring functions XX
Control of circuit-breaker XX
Flexible protection functions (current parameters) XX
Inrush restraint XX
48 Start time supervision X
Motor statistics X
14 Locked rotor protection X
51M Load jam protection X
66/86 Restart blocking X