Setting Notes - Siemens siprotec SJ62 User Manual

2.2.10 Setting Notes

General
SIPROTEC 4, 7SJ62/63/64 Handbuch
C53000-G1140-C147-A, Edition 07.2015
Figure 2-12 Reverse interlocking protection scheme
When selecting the time overcurrent protection in DIGSI a dialog box appears with
several tabs, such as General, 50, 51, 50N, 51N and InrushRestraint for setting indi-
vidual parameters. Depending on the functional scope specified during configuration
of the protective functions in addresses 112 Charac. Phase and 113 Charac.
Ground the number of tabs can vary. If address FCT 50/51 was set to Definite
Time, or Charac. Ground to = Definite Time, then only the settings for the def-
inite time elements are available. The selection of TOC IEC or TOC ANSI makes avail-
able additional inverse characteristics. The superimposed high-set elements 50-2 and
50N-2 are available in all these cases. Parameter 250 50/51 2-ph prot can also
be set to activate two-phase overcurrent protection.
At address 1201 FCT 50/51 the phase time-overcurrent protection and at address
1301 FCT 50N/51N the ground time-overcurrent protection may be switched ON or
OFF.
Pickup values, time delays, and characteristics for ground protection are set separate-
ly from the pickup values, time delays and characteristic curves associated with phase
protection. Because of this, relay coordination for ground faults is independent of relay
coordination for phase faults, and more sensitive settings can often be applied to di-
rectional ground protection.
2.2 Overcurrent Protection 50, 51, 50N, 51N
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