Auto-Reclosing Operation Off And On - ABB Relion REC670 Applications Manual

1MRK 511 358-UEN A
check. In order to limit the stress on turbo-generator sets from Auto-Reclosing onto a
permanent fault, one can arrange to combine Auto-Reclosing with a synchrocheck on line
terminals close to such power stations and attempt energizing from the side furthest away
from the power station and perform the synchrocheck at the local end if the energizing was
successful.
Transmission protection systems are usually sub-divided and provided with two redundant
protection IEDs. In such systems it is common to provide auto-reclosing in only one of the sub-
systems as the requirement is for fault clearance and a failure to reclose because of the auto-
recloser being out of service is not considered a major disturbance. If two auto-reclosers are
provided on the same breaker, the application must be carefully checked and normally one
must be the master and be connected to inhibit the other auto-recloser if it has started. This
inhibit can for example be done from Autorecloser for 3-phase operation(SMBRREC) In
progress.
When Single and/or three phase auto-reclosing is considered, there are a number of cases
where the tripping shall be three phase anyway. For example:
• Evolving fault where the fault during the dead-time spreads to another phase. The other
two phases must then be tripped and a three phase dead-time and auto-reclose initiated
• Permanent fault
• Fault during three phase dead-time
• Auto-reclose out of service or CB not ready for an auto-reclosing cycle
"Prepare three-phase tripping" is then used to switch the tripping to three-phase. This signal
is generated by the auto-recloser and connected to the trip function block and also connected
outside the IED through IO when a common auto-recloser is provided for two sub-systems. An
alternative signal "Prepare 1 Phase tripping" is also provided and can be used as an alternative
when the autorecloser is shared with another subsystem. This provides a fail safe connection
so that even a failure in the IED with the auto-recloser will mean that the other sub-system will
start a three-phase trip.
A permanent fault will cause the line protection to trip again when it recloses in an attempt to
energize the line.
The auto-reclosing function allows a number of parameters to be adjusted.
Examples:
• number of auto-reclosing shots
• auto-reclosing program
• auto-reclosing open times (dead time) for each shot
13.2.2.1

Auto-reclosing operation OFF and ON

Operation of the automatic reclosing can be set OFF and ON by a setting parameter and by
external control. Parameter
settings
the inputs ON and OFF, for example, from the control system or from the binary input (and
other systems).
When the function is set ON, the output SETON is set, and it become operative if other
conditions such as CB closed and CB Ready are also fulfilled, the output READY is activated
(high). When the function is ready to accept a reclosing start.
Application manual
Operation = Off , or On sets the function OFF and ON. With the
Operation = On and ExternalCtrl = On , the control is made by input signal pulses to
Section 13
Control
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