GE 750 - Page 287

GE Power Management
750/760 Feeder Management Relay 14-
31
14 S7 CONTROL 14.8 AUTORECLOSE (760 ONLY)
14
14.8.2 SCHEME SETUP
The setpoints shown in this section setup the general characteristics of the scheme. The
AUTORECLOSE FUNC-
TION
and
MAXIMUM NUMBER OF RECLOSURE SHOTS
setpoints are critical and must be set appropriately.
NOTE: For an overcurrent element to initiate a reclosure it must be set to the ‘Tri
p
& AR’ function.
■ SCHEME SETUP
■ [ENTER] for more
The Autoreclose Scheme Setup setpoints path is:
\ SETPOINTS \ S7 CONTROL \ AUTORECLOSE \ SCHEME SETUP
AUTORECLOSE
FUNCTION: Disabled
Range: Enabled, Disabled
Enter Enabled to enable the autoreclose scheme.
MAXIMUM NUMBER OF
RECLOSURE SHOTS: 1
Range: 1 to 4 in steps of 1
Specify the number of reclosures that should be attempted before reclosure
lockout occurs. The dead time and overcurrent characteristics for each reclo-
sure shot are entered in the subsequent message groups RECLOSURE 1-4.
AUTORECLOSE RESET
TIME: 60 s
Range: 1 to 1000 in steps of 1 s
The reset timer is used to set the total time interval for a single fault event, from
the first trip until either lockout or successful reclosure. Generally, this setpoint
is set to the same delay that would be used for the ‘reclaim time’ in a traditional
scheme with fixed protection settings. This time must be set to a value greater
than the sum of all programmed dead times plus the maximum time to trip on
each reclose shot.
NOTE: Set this timer to a dela
y
lon
g
er than the incom
p
lete se
q
uence
timer.
AR BLOCK TIME UPON
MANUAL CLOSE: 10 s
Range: 0 to 200 in steps of 1 s
The autoreclose scheme can be disabled for a programmable time delay after
the associated circuit breaker is manually closed. This prevents manual reclos-
ing onto a fault. This delay must be longer than the slowest expected trip from
any protection not blocked after manual closing. If no overcurrent trips occur
after a manual close and this timer expires, the autoreclose scheme is auto-
matically reset. The lockout state will be cleared and the shot counter will be
set to zero.
Note that manual circuit breaker closures can be initiated by either the front
panel breaker CLOSE key when in local mode, or by the REMOTE CLOSE
logic input and computer communications when in remote mode.