(1) Description of Operation 7SR224
Page 46 of 66 ©2009 Siemens Protection Devices Limited
4.1.7 EXTERN SHOTS sub-menu
This menu allows the External Protection auto-reclose sequence to be parameterized:-
79 P/F Prot’n Trip1 Not Blocked/Blocked - Blocked raises an output which can be mapped to a
Binary output to Block an External Protection’s Trip Output.
79 P/F Deadtime 1 Sets the first Reclose Delay ( Deadtime) for the External sequence.
79 P/F Prot’n Trip2 Not Blocked/Blocked - Blocked raises an output which can be mapped to a
Binary Output to Block an External Protection’s second Trip output.
79 P/F Deadtime 2 Sets the second Reclose Delay ( Deadtime) in the External sequence.
79 P/F Prot’n Trip3 Not Blocked/Blocked - Blocked raises an output which can be mapped to a
Binary output to Block an External Protection’s third Trip Output.
79 P/F Deadtime 3 Sets the third Reclose Delay (Deadtime) in the External sequence.
79 P/F Prot’n Trip4 Not Blocked/Blocked - Blocked raises an output which can be mapped to a
Binary output to Block an External Protection’s fourth Trip Output.
79 P/F Deadtime 4 Sets the fourth Reclose Delay (Deadtime) in the External sequence.
79 P/F Prot’n Trip5 Not Blocked/Blocked - Blocked raises an output which can be mapped to a
Binary output to Block an External Protection’s fifth Trip Output.
79 P/F Extern Trips to Lockout - Sets the number of allowed External protection’ trips, Relay will go
to Lockout on the last Trip.
These settings allow the user to set-up a separate AutoReclose sequence for external protection(s)
having a different sequence to P/F, E/F or SEF protections. The ‘ Blocked ‘ setting allows the
Autoreclose sequence to raise an output at any point in the sequence to Block further Trips by the
External Protection thus allowing the Overcurrent P/F or Earth Fault or SEF elements to apply
Overcurrent Grading to clear the fault.
Other Protection Elements in the Relay can also be the cause of trips and it may be that AutoReclose
is required; the External AutoReclose sequence can be applied for this purpose. By setting-up internal
Quick Logic equation(s) the user can define and set what should occur when any one of these other
elements operates.
Note: If the ‘CB Total Trip Count’ or the ‘CB Frequent Ops Count’ target is reached the relay will do
one delayed tip and lockout*.
*NB: If Delayed Trips are not assigned in the AUTORECLOSE PROT’N menu the relay will not trip.
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