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The dead time is initiated when the trip output contact reset, the pickup is reset and the CB is open.
The CB close output relay is energised after the dead time has elapsed.
Figure 4-1 Typical AR Sequence with 3 Inst and 1 Delayed trip
4.1.3
A
UTORECLOSE
This menu presents the Overcurrent Protection elements available for each type of Fault i.e. P/F, E/F (N/G) or
SEF and allows the user to select those that are to be applied as Inst trips; those that are to be applied as
Delayed Trips; and those that are to be applied as HS Trips (HighSet), as required by the selected sequence.
There is no corresponding setting for External as the External protection type is not normally controlled by the
Auto Reclose Relay. The resultant configuration enables the Auto Reclose function to correctly apply the required
Protection for each shot in a sequence.
4.1.4
A
UTORECLOSE
This menu allows the following settings to be made:-
79 Autoreclose
79 Num Shots
79 Retry Enable
79 Retry Attempts
79 Retry Interval
79 Reclose Blocked
Delay
79 Sequence Fail Timer Sets the time that AutoReclose start can be primed. Where this time expires before all
©2017 Siemens Protection Devices Limited
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'
M
ROT
N
ENU
C
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ONFIG
ENU
Enabled turns ON all AutoReclose Functions.
Sets the allowed number of AutoReclose attempts in a sequence.
Enabled configures the relay to perform further attempts to automatically Close the
Circuit Breaker where the CB has initially failed to close in response to a Close
command. If the first attempt fails the relay will wait for the 79 Retry Interval to expire
then attempt to Close the CB again.
Sets the maximum number of retry attempts.
Sets the time delay between retry attempts.
If the CB is not ready to receive a Close command or if system conditions are such
that the CB should not be closed immediately e.g. a close-spring is not charged, then
a Binary input mapped to Reclose Block can be raised and the Close pulse will not be
issued but will be held-back. The 79 Reclose Blocked Delay sets the time Reclose
Block is allowed to be raised, if this time delay expires the Relay will go to Lockout. If
Reclose Block is cleared, before this time expires, then the CB Close pulse will be
issued at that point in time. Dead Time + Reclose Blocked Delay = Lockout.
the DAR start signals are not received i.e. the CB has opened, protection pickups have
reset and the trip relay has reset, the Relay goes to Lockout.
7SR11 & 7SR12 Description Of Operation
Chapter 1 Page 63 of 88
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