ABB REF 610 Technical Reference Manual page 31

1MRS 755535
Feeder Protection Relay
Technical Reference Manual - ANSI Version
The AR function will issue an opening command to the circuit breaker at shot
initiation by a pickup or a trip signal.
CB Closed
0
100ms
Shot Due
50P-1 Trip
External AR Initiation
51P Trip
51P pickup delay
51P Pickup
t
0
50N Trip
51N Trip
51N pickup delay
51N Pickup
t
0
Fig. 4.1.4.8.-2 Simplified shot initiation logic diagram
Blocking of shot initiation
The initiation of one or several auto-reclose shots can be set to be blocked by any of
the following signals:
• external AR initiation signal
• trip signal from overcurrent elements 51P and 50P-1
• trip signal from ground-fault elements 51N and 50N
The selection is made in SG1 (see table 4.1.4.10-10).
Blocking of shot initiation can also be used to skip the entire shot sequence (by
blocking the initiation of all three shots), and go directly to definite tripping. Further,
it can be used, for instance, to allow shot initiation by the trip signal from element
51P, but to go directly to definite tripping in case of shot initiation by the trip signal
from element 50P-1.
Note!
Activation of any above-mentioned signal will always cause the AR function to
issue an opening command to the circuit breaker. If the signal used for blocking is
not simultaneously used for initiation of the next shot, the AR function will generate
a definite trip alarm and be locked out.
Note!
Shot initiation is blocked only for as long as the blocking signal is active.
Blocking of shot
SG1/
1..8
REF 610
Shot Initiation
Open CB Command
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