ABB REF 610 - Page 38

t
100 ms
t
SG1/
1...8
t
AND
I>> Trip
Ext AR Initiation
I> Trip
I> Start
*)
Io>> Trip
Io> Trip
Open CB Command
CB position closed
Shot Due
AND
Shot Initiation
Blocking of shot
Io> Start
*)
*)
Shot initiation by a start signal applies only to shot 1 and definite tripping.
OR
OR
OR
Io> start delay
I> start delay
A040318
Fig. 5.1.4.8.-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 stages I> and I>>
*
Trip signal from earth-fault stages I
0
> and I
0
>>
The selection is made in SG1 (see Table 5.1.4.10.-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
stage I>, but to go directly to definite tripping in case of shot initiation by the trip
signal from stage I>>.
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.
Shot initiation is blocked only for as long as the blocking signal is
active.
In case of shot initiation while a blocking is active, the next shot (if
such has been selected and not blocked) will be initiated. This can be
used to skip Shot 1, for instance.
38
REF 610REF 610
Feeder Protection Relay
Technical Reference Manual
1MRS755310