SGC
3.4 OPERATION
Sectionaliser operational principle is based on the use of fault pass detector to monitor the main circuit
breaker reclosing cycle.
The voltage presence detector is used to verify whether the reclosing cycle has succeeded or not.
At first, the automatism is awaiting a fault pass indication. When it occurs a timer T, corresponding to the
first reclosing cycle, is started.
If there is a fault pass detection during the T time, and there is not voltage presence on the line, a failed
reclosing cycle is assumed. Then the T timer is restarted.
If there is not a fault pass detection during the T time, or a fault is detected but with voltage presence on
the line, it is assumed the fault has been cleared, so the automatism returns to the initial state.
If the current reclosing cycle is the last one programmed, the voltage presence is checked once the timer
is expired.
If the fault has been cleared, the automatism returns to the initial state (example a).
If the fault has not been cleared (example b), the associated circuit breaker open command is issued (no
voltage on line).
The command is executed as a programmable pulse/latch signal according to the setting “Command
Time”.
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00110E4
Summary of Contents for SGC Series
Page 31: ...6 FUNCTIONS 00110E4 EDP 26 Illustration 8 VPD unit logic diagram ...
Page 53: ...10 SCHEMATICS 10 SCHEMATICS 00110E4 EDP 48 ...
Page 54: ...SGC 49 EDP 00110E4 ...
Page 55: ...10 SCHEMATICS 00110E4 EDP 50 Illustration 13 Connection diagram ...
Page 56: ...SGC Illustration 14 SGC195 Connection diagram 51 EDP 00110E4 ...
Page 58: ...SGC 11 SIZE 53 EDP 00110E4 Drawing 1 Front and side views of SGC180 and SGC195 devices ...
Page 59: ...11 SIZE Drawing 2 Top and bottom view of SGC180 device 00110E4 EDP 54 ...
Page 60: ...SGC Drawing 3 Top and bottom view of SGC195 device 55 EDP 00110E4 ...
