ABB RELION REF615R, Техническое руководство

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A sequence initiation from the
INIT_4
line leads to a lockout after two shots. In a
situation where the initiation is made from both the
INIT_3
and
INIT_4
lines, a third
shot is allowed, that is, CBB3 is allowed to start. This is called conditional lockout. If the
initiation is made from the
INIT_2
and
INIT_3
lines, an immediate lockout occurs.
The
INIT_5
line is used for blocking purposes. If the
INIT_5
line is active during a
sequence start, the reclose attempt is blocked and the AR function goes to lockout.
When the reclose time of a CBB is set to zero, once its init line is active,
it immediately goes to lockout.
If more than one CBBs are started with the shot pointer, the CBB with the
smallest individual number is always selected. For example, if the
INIT_2
and
INIT_4
lines are active for the second shot, that is, the shot
pointer is 2, CBB2 is started instead of CBB5.
Even if the initiation signals are not received from the protection functions, the AR
function can be set to continue from the second to the fifth reclose shot. The AR function
can, for example, be requested to automatically continue with the sequence when the
circuit breaker fails to close when requested. In such a case, the AR function issues a
CLOSE_CB
command. When the wait close time elapses, that is, the closing of the circuit
breaker fails, the next shot is automatically started. Another example is the embedded
generation on the power line, which can make the synchronism check fail and prevent the
reclosing. If the autoreclose sequence is continued to the second shot, a successful
synchronous reclosing is more likely than with the first shot, since the second shot lasts
longer than the first one.
The existing 79 function does not have a complete zone sequence coordination feature. An
external ACT logic needs to be built to drive INC_POINT.
1MRS240050-IB C
Section 9
Control functions
REF615R 467
Technical Manual