Siemens SIPROTEC 7SD610 Manual page 130

Functions
2.10 Automatic Reclosure Function (optional)
If the fault is cleared (successful reclosure), the reclaim time expires and all functions return to their quiescent
state. The fault is cleared.
If the fault has not been eliminated (unsuccessful reclosure), the short-circuit protection initiates a final trip fol-
lowing a protection stage active without reclosure. Any fault during the reclaim time leads to a final trip.
After unsuccessful reclosure (final tripping) the automatic reclosure function is blocked dynamically (see also
margin heading „Reclose Block", above).
The sequence above applies for single reclosure cycles. In 7SD610 multiple reclosure (up to 8 shots) is also
possible (see below).
Sequence of a 1-pole reclose cycle
1-pole reclose cycles are only possible with the appropriate device version and if this was selected during the
configuration of the protection functions (address 110 Trip mode, see also Section 2.1.1.2). Of course, the
circuit breaker must also be suitable for 1-pole tripping.
If the automatic reclosure function is ready, the short-circuit protection trips 1-pole for all 1-phase faults inside
the stage(s) selected for reclosure. Under the general settings (address 1156 Trip2phFlt, see also Section
2.1.4.1) it can also be selected that 1-pole tripping takes place for two-phase faults without earth. 1-pole tripping
is of course only possible by short-circuit protection functions which can determine the faulty phase.
If multiple-phase faults occur, the fault protection issues a final 3-pole trip with the stage that is valid without
reclosure. Any 3-pole trip is final. The automatic reclosure function is blocked dynamically (see also margin
heading „Blocking reclosure", above).
The automatic reclosure function is started in the case of 1-pole tripping. The (adjustable) dead time for the 1-
pole reclose cycle starts with reset of the trip command or opening of the circuit breaker pole (auxiliary contact
criterion). After expiry of the dead time, the circuit breaker receives a close command. At the same time, the
(adjustable) reclaim time is started. If the reclosure is blocked during the dead time following a 1-pole trip, im-
mediate 3-pole tripping can take place as an option (forced 3-pole trip).
If the fault is cleared (successful reclosure), the reclaim time expires and all functions return to their quiescent
state. The fault is cleared.
If the fault has not been eliminated (unsuccessful reclosure), the short-circuit protection initiates a final 3-pole
trip with the protection stage that is valid without reclosure. All faults during the reclaim time also lead to a final
3-pole trip.
After unsuccessful reclosure (final tripping) the automatic reclosure function is blocked dynamically (see also
margin heading „Reclose Block", above).
The sequence above applies for single reclosure cycles. In 7SD610 multiple reclosure (up to 8 shots) is also
possible (see below).
Sequence of a 1-pole and 3-pole Reclose Cycle
This operating mode is only possible with the appropriate device version if selected during configuration of the
protection functions (address 110, see also Section 2.1.1.2). Also, the circuit breaker must be suitable for 1-
pole tripping.
If the automatic reclosure function is ready, the short-circuit protection trips 1-pole for 1-phase faults and 3-pole
for multi-phase faults. Under the general settings (address 1156 Trip2phFlt, see also Section 2.1.4.1) 1-
pole tripping for two-phase faults without earth can be selected. 1-pole tripping is only possible for short-circuit
protection functions that can determine the faulted phase. The valid protection stage selected for reclosure
ready state applies for all fault types.
The automatic reclosure function is started at the moment of tripping. Depending on the type of fault, the (ad-
justable) dead time for the 1-pole reclose cycle or the (separately adjustable) dead time for the 3-pole reclose
cycle starts following the reset of the trip command or opening of the circuit breaker (pole) (auxiliary contact
criterion). After expiry of the dead time, the circuit breaker receives a close command. At the same time, the
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SIPROTEC, 7SD610, Manual
C53000-G1176-C145-6, Release date 02.2011