ABB REL650 - Page 324

time selected should be long enough to ensure a high probability of arc de-ionization and
successful reclosing.
For individual line breakers, auto-reclosing equipment or functions, the autoreclosing
open time is used to determine line “dead time”. When simultaneous tripping and
reclosing at the two line ends occurs, auto-reclosing open time is approximately equal to
the line “dead time”. If the open time and dead time differ then, the line will be energized
until the breakers at both ends have opened.
ANSI10000197_1_en.vsd
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Fault duration
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Break timeClosing time
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Set STBRREC (79) open time Reset time
Auto- reclosing
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ANSI10000197 V1 EN
Figure 140: Single-shot automatic reclosing at a permanent fault
Single-pole tripping and single-pole automatic reclosing is a way of limiting the effect of
a single-phase line fault on power system operation. Especially at higher voltage levels,
the majority of faults are of single-phase type (around 90%). To maintain system stability
in power systems with limited meshing or parallel routing single phase auto reclosing is
of particular value. During the single phase dead time the system is still capable of
transmitting load on the two healthy phases and the system is still synchronized. It requires
Section 11 1MRK 506 334-UUS A
Control
318
Application manual