Functions
Synchronism
check conditions
before automatic
reclosure
Synchronism
check conditions
before manual
closing
6-186
Addresses to are relevant to the check conditions before automatic
reclosure of the circuit breaker. When setting the parameters for the internal
automatic reclosing function (Section 6.11.2) it is decided with which automatic
reclosing cycle synchronism and voltage check should be carried out.
Address 2SPRGH ZLWK $5 determines whether closing under asynchronous
system conditions is allowed. Set this parameter to ZLWK 7&% FORVH, if asynchro-
nous closing shall be allowed; the relay will then consider the circuit breaker closing
time before determining the correct instant for the closing command. Remember that
closing under asynchronous system conditions is allowed only if the circuit breaker
closing time is set correctly (see above under Preconditions)! If you wish to permit au-
tomatic reclosure only under synchronous system conditions, set this address to
ZR 7&% FORVH.
The permissible magnitude difference of the voltages is set under address 0D[
9ROW 'LII. Setting is in volts secondary; when operating the device from a person-
al computer using DIGSI
ing on the connection of the bus-bar voltage (phase–phase or phase–earth) the
phase–phase or the phase–earth voltage is decisive.
The permissible frequency difference between the voltages is set under address
0D[ )UHT 'LII, the permissible phase angle difference under address
0D[ $QJOH 'LII.
The further release conditions for automatic reclosing are set under addresses $
to :
$ 6<1&&+(&.
8V\QF! 8OLQH
8V\QF 8OLQH!
8V\QF 8OLQH
29(55,'(
The five possible release conditions are independent of each other and can be com-
bined.
The release conditions for manual closing are set under addresses to .
When setting the general protection data (Power System Data 2, Section 6.1.3) it was
decided whether synchronism and voltage check should be carried out before manual
closing. With the following setting in address 6<10$1&/ = ZR 6\QF
FKHFN, no checks are performed before manual closing. The following parameters are
then irrelevant.
®
4, setting may be in secondary or primary values. Depend-
= synchronism check: the bus-bar (Ubus) and the
feeder (Uline) must both be live (/LYH 9ROW
7KU, address ); the conditions for synchro-
nism 0D[ 9ROW 'LII (address ), 0D[
)UHT 'LII (address ), and 0D[ $QJOH
'LII (address ) are checked before automatic
reclosure;
= dead-line check: the bus-bar (Ubus) must be live
(/LYH 9ROW 7KU, refer to address ), the
feeder (Uline) must be dead ('HDG 9ROW 7KU,
refer to address );
= dead-bus check: the bus-bar (Ubus) must be dead
('HDG 9ROW 7KU, refer to address ), the
feeder (Uline) must be live (/LYH 9ROW 7KU, re-
fer to address );
= dead-bus and dead-line check: the bus-bar (Ubus)
and the feeder (Uline) must both be dead ('HDG
9ROW 7KU, refer to address );
automatic reclosure is released without any check.
7SA522 Manual
C53000-G1176-C119-2