ABB 615 Series ANSI, Техническое руководство

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Section 7
1MAC050144-MB C
Control functions
510 615 series ANSI
Technical Manual
Operation in a permanent fault:
1. Protection picks up and activates the
DEL_INIT 2
input.
2. After 0.05 seconds, the first autoreclose shot is initiated. The function opens the
circuit breaker: the
OPEN_CB
output activates. The total trip time is the protection
pickup delay + 0.05 s the time it takes to open the circuit breaker.
3. After the first shot, the circuit breaker is reclosed and the protection picks up again.
4. Because the delay of the second shot is 60 seconds, the protection is faster and trips
after the set operation time, activating the
INIT 2
input. The second shot is initi-
ated.
5. After the second shot, the circuit breaker is reclosed and the protection picks up
again.
6. Because the delay of the second shot is 60 seconds, the protection is faster and trips
after the set operation time. No further shots are programmed after the final trip. The
function is in lockout and the sequence is considered unsuccessful.
Example 2
The delays can be used also for fast final trip. The conditions are the same as in Example
1, with the exception of
Str 2 delay shot 3 = 0.10 seconds.
The operation in a permanent fault is the same as in Example 1, except that after the second
shot when the protection picks up again,
Str 2 delay shot 3 elapses before the protection
trip time and the final trip follows. The total trip time is the protection pickup delay + 0.10
s the time it takes to open the circuit breaker.
7.2.6.6 Fast trip in Switch on to fault
The Str _ delay shot 4 parameter delays can also be used to achieve a fast and accelerated
trip with SOTF. This is done by setting the Fourth delay in SOTF parameter to "1" and
connecting the protection pickup information to the corresponding
DEL_INIT_
input.
When the function detects a closing of the circuit breaker, that is, any other closing except
the reclosing done by the function itself, it always prohibits shot initiation for the time set
with the
Reclaim time parameter. Furthermore, if the Fourth delay in SOTF parameter is
"1", the Str _ delay shot 4 parameter delays are also activated.
Example 1
The protection operation time is 0.5 seconds, the Fourth delay in SOTF parameter is set to
"1" and the Str 2 delay shot 4 parameter is 0.05 seconds. The protection pickup signal is
connected to the
DEL_INIT_2
input.
If the protection picks up after the circuit breaker closes, the fast trip follows after the set
0.05 seconds. The total trip time is the protection pickup delay + 0.05 s the time
it takes to open the circuit breaker.