CHAPTER 5: SETTINGS
CONTROL ELEMENTS
F35 MULTIPLE FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL
5-269
5
The reclosure scheme is considered enabled when all of the following conditions are true:
•
The
AR1 FUNCTION
is set to “Enabled”
•
The scheme is not in the "Lockout" state
•
The "Block" input is not asserted
•
The
AR1 BLK TIME UPON MNL CLS
timer is not active
The autoreclose scheme is initiated by a trip signal from any selected protection feature operand. The scheme is initiated
provided the circuit breaker is in the closed state before protection operation.
The reclose-in-progress (RIP) is set when a reclosing cycle begins following a reclose initiate signal. Once the cycle is
successfully initiated, the RIP signal seals-in and the scheme continues through its sequence until one of the following
conditions is satisfied:
•
The close signal is issued when the dead timer times out, or
•
The scheme goes to lockout
While RIP is active, the scheme checks that the breaker is open and the shot number is below the limit, and then begins
measuring the dead time.
Each of the four possible shots has an independently settable dead time. Two additional timers can be used to increase the
initial set dead times 1 to 4 by a delay equal to
AR1 DELAY 1
or
AR1 DELAY 2
or the sum of these two delays depending on the
selected settings. This offers enhanced setting flexibility using FlexLogic operands to turn the two additional timers “on”
and “off.” These operands can possibly include
AR1 SHOT CNT =n
,
SETTING GROUP ACT 1
, and so on. The autoreclose provides
up to maximum 4 selectable shots. Maximum number of shots can be dynamically modified through the settings
AR1
REDUCE MAX TO 1 (2, 3)
, using the appropriate FlexLogic operand.
Scheme lockout blocks all phases of the reclosing cycle, preventing automatic reclosure, if any of the following occurs:
•
The maximum shot number was reached
•
A "Block" input is in effect (for instance, Breaker Failure or bus differential protection operated)
•
The "Incomplete Sequence" timer times out
The recloser is latched in the Lockout state until a "reset from lockout" signal is asserted, either from a manual close of the
breaker or from a manual reset command (local or remote). The reset from lockout can be accomplished by operator
command, by manually closing the breaker, or whenever the breaker has been closed and stays closed for a preset time.
After the dead time elapses, the scheme issues the close signal. The close signal is latched until the breaker closes or the
scheme goes to Lockout.
A reset timer output resets the recloser following a successful reclosure sequence. The reset time is based on the breaker
"reclaim time," which is the minimum time required between successive reclose sequences.
5.8.6.1 Settings
AR1 INITIATE
— Selects the FlexLogic operand that initiates the scheme, typically the trip signal from protection.
AR1 BLOCK
— Selects the FlexLogic operand that blocks the autoreclosure initiate (it can be from the breaker failure, bus
differential protection, and so on).
AR1 MAX NUMBER OF SHOTS
— Specifies the number of reclosures that can be attempted before reclosure goes to “Lockout”
because the fault is permanent.
AR1 REDUCE MAX TO 1(3)
— Selects the FlexLogic operand that changes the maximum number of shots from the initial
setting to 1, 2, or 3, respectively.
AR1 MANUAL CLOSE
— Selects the logic input set when the breaker is manually closed.
AR1 MNL RST FRM LO
— Selects the FlexLogic operand that resets the autoreclosure from Lockout condition. Typically this is
a manual reset from lockout, local or remote.
AR1 RESET LOCKOUT IF BREAKER CLOSED
— This setting allows the autoreclose scheme to reset from Lockout if the breaker
has been manually closed and stays closed for a preset time. In order for this setting to be effective, disable the next
setting (
AR1 RESET LOCKOUT ON MANUAL CLOSE
).
