Functions
2.14 Automatic Reclosing System 79
SIPROTEC, 7SJ62/64, Manual
C53000-G1140-C207-2, Release date 01.2008
259
Figure 2-97 Control of protection elements for two-fold, successful auto-reclosure
Example:
Before the first reclosing, faults are to be eliminated quickly applying elements 50-2 or 50N-2. Fast fault termi-
nation thus has priority over selectivity aspects as the reclosing action aims at maintaining normal system op-
eration. If the fault prevails, a second tripping is to take place instantaneously and subsequently, a second re-
closing.
After the second reclosing, however, elements 50-2 or 50N-2 are to be blocked so the fault can be eliminated
by applying elements 50-1 or 50N-1 according to the grading coordination chart of the system giving priority to
selectivity concerns.
Addresses 7202 bef.1.Cy:50-2, 7214 bef.2.Cy:50-2, 7203 bef.1.Cy:50N-2 and 7215
bef.2.Cy:50N-2 are set to instant. T=0 to enable the elements after the first reclosing. Addresses 7226
bef.3.Cy:50-2 and 7227 bef.3.Cy:50N-2, however, are set to blocked T=∞, to ensure that elements
50-2 and 50N-2 are blocked when the second reclosing applies. The back-up elements, e.g. 50-1 and 50N-1,
must obviously not be blocked (addresses 7200, 7201, 7212, 7213, 7224 and 7225).
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