5-348
L60 LINE PHASE COMPARISON SYSTEM – INSTRUCTION MANUAL
CONTROL ELEMENTS
CHAPTER 5: SETTINGS
5
The autoreclose scheme is intended for use on transmission lines with circuit breakers operated in both the single pole and
three pole modes, in one or two breaker arrangements. The autoreclose scheme provides four programs with different
operating cycles, depending on the fault type. Each of the four programs can be set to trigger up to four reclosing
attempts. The second, third, and fourth attempts always perform three-pole reclosing and have independent dead time
delays.
When used in two breaker applications, the reclosing sequence is selectable. The reclose signal can be sent to one
selected breaker only, to both breakers simultaneously or to both breakers in sequence (one breaker first and then, after a
delay to check that the reclose was successful, to the second breaker). When reclosing in sequence, the first breaker
should reclose with either the single-pole or three-pole dead time according to the fault type and reclose mode; the second
breaker should follow the successful reclosure of the first breaker. When reclosing simultaneously, for the first shot both
breakers should reclose with either the single-pole or three-pole dead time, according to the fault type and the reclose
mode.
The signal used to initiate the autoreclose scheme is the trip output from protection. This signal can be single pole tripping
for single phase faults and three phase tripping for multi-phase faults. The autoreclose scheme has five operating states.
Table 5-41: Autoreclose states
Autoreclose programs
The autorecloser provides four programs that can cause from one to four reclose attempts (shots). After the first shot, all
subsequent recloses are always three-pole. If the maximum number of shots selected is “1” (only one reclose attempt) and
the fault is persistent, after the first reclose the scheme goes to lockout upon another Initiate signal.
For the three-pole reclose programs (modes 3 and 4), an
AR FORCE 3-P
FlexLogic operand is set. This operand can be used in
connection with the tripping logic to cause a three-pole trip for single-phase faults.
AR TRANSFER 1 TO 2:
No
Range: Yes, No
AR TRANSFER 2 TO 1:
No
Range: Yes, No
AR BKR1 FAIL OPTION:
Continue
Range: Continue, Lockout
AR BKR2 FAIL OPTION:
Continue
Range: Continue, Lockout
AR 1-P DEAD TIME:
1.00 s
Range: 0 to 655.35 s in steps of 0.01
AR BKR SEQUENCE:
1-2
Range: 1, 2, 1&2, 1–2, 2–1
AR TRANSFER TIME:
4.00 s
Range: 0 to 655.35 s in steps of 0.01
AR BUS FLT INIT:
Off
Range: FlexLogic operand
AR EVENT:
Disabled
Range: Enabled, Disabled
State
Characteristic
Enabled
Scheme is permitted to operate
Disabled
Scheme is not permitted to operate
Reset
Scheme is permitted to operate and shot count is reset to 0
Reclose in progress
Scheme has been initiated but the reclose cycle is not finished (successful or not)
Lockout
Scheme is not permitted to operate until reset received