The menus, allow the user to set independent protection and autoreclose sequences for each type of fault i.e.
phase fault (P/F), calculated/measured earth fault, sensitive earth fault or external protections.
Each autoreclose sequence can be user set to up to 4-shots i.e.5 trips + 4 reclose sequence, with independ-
ently configurable types of Protection Trip. Overcurrent and earth fault elements can be assigned to any
combination of fast (Inst), delayed or highset (HS) trips. Deadtime Delay time settings are independent for
each AR shot. The user has programming options for autoreclose sequences up to the maximum shot count
i.e.
•
Inst or Delayed Trip 1 + (DeadTime 1: 0.1 s to 14400 s)
•
+ Inst or Delayed Trip 2 + (DeadTime 2: 0.1 s to 14400 s)
•
+ Inst or Delayed Trip 3 + (DeadTime 3: 0.1 s to 14400 s)
•
+ Inst or Delayed Trip 4 + (DeadTime 4: 0.1 s to 14400 s)
•
+ Inst or Delayed Trip 5 – Lockout.
The AR function recognizes developing faults and, as the shot count advances, automatically applies the
correct type of protection and associated dead time for that fault type at that point in the sequence.
A typical sequence would consist of 2 inst trips followed by at least 1 delayed trip. This sequence enables tran-
sient faults to be cleared quickly by the inst trip(s) and permanent fault to be cleared by the combined delayed
trip. The delayed trip must be graded with other recloser/CB’s to ensure system discrimination is maintained,
ie. that as much of the system as possible is live after the fault is cleared.
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
autoreclose relay. The resultant configuration enables the Automatic Reclosing function to correctly
apply the required protection for each shot in a sequence.
Control Functions
7.3 79 Automatic Reclosing
Reyrolle 7SR5, Overcurrent Protection Device, Device Manual 423
C53000-G7040-C014-1, Edition 11.2019
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