ABB XT7, Руководство по эксплуатации и обслуживанию

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ABB | SACE Tmax XT
Protections | 15 - Additional protections and functions 77 | © 2020 ABB | 1SDH001821A1002 - ECN000135670
Continued from the previous page
Configuration
To correctly configure selectivity D in a ring system:
1. Connect the zone selectivity outputs of each device (example: DFin) to the selectivity input of the same
direction as the device immediately after (example: DFout).
2. Connect all the Szc of devices in the same network together.
Logic table
The table includes all cases in which, with zone selectivity enabled in the device, an alarm condition occurs
or a zone selectivity signal is received from another device.
The Forward output is activated if the
fault direction coincides with the reference direction otherwise, if it
is in the opposite direction, the Backward output is activated (page 64)
Fault
direction
Condition
DFin Dbin Dfout Dbout
Tripping
time
Remarks
Forward If < I7 Fw 0 x 0 x
No TRIP Device not in alarm status
Backward If < I7 Bw x 0 x 0
Forward If < I7 Fw 1 x 1 x
No TRIP
The device is not in the alarm status, but
sends the selecitivity signal received to the
output of the reference direction
Backward If < I7 Bw x 1 x 1
Forward If > I7 Fw 0 x 1 x t7 Fw sel The device is in the alarm status and is the
first to detect the fault: trips within time t7 Fw
sel or t7 Bw sel
Backward If > I7 Bw x 0 x 1 t7 Bw sel
Forward If > I7 Fw 1 x 1 x t7 Fw The device is in the alarm status but is not the
first to detect the fault: trips within time t7 Fw
(or t7 Bw)
Backward If > I7 Bw x 1 x 1 t7 Bw
NOTE:
when zone selectivity is active and the direction of the fault cannot be established,
the unit trips by considering the first threshold to be exceeded between I7 Fw and I7
Bw, without activating any output (DFout or Dbout).; if both the thresholds have been exceeded
(for example, if they have been set with the same value), the unit trips after the shortest time
between t7 Fw and t7 Bw.
Trip Only Forward and
Backward
D protection can be configured (if available and enabled) with 2 additional parameters via the service
connector (via Ekip Connect) or via system bus communication:
• Trip only Forward : if activated, D protection only controls open commands if forward direction is detected
•
Trip only Backward
: if activated, D protection only controls open commands if backward direction is detected
faults in the opposite direction are only handled as alarm information.
Type of selectivity
The zone selectivity inputs and certain of the outputs can be configured via service connector (via Ekip
Connect) or via system bus communication for protections S, S2, I, 2I, MCR, G, Gext, MDGF and D (if
available and enabled):
• Standard : operation as by zone selectivity standard logic (default configuration)
• Customized : the event that activates the zone selectivity input or output can be selected in this mode.
IMPORTANT: in the Customized configuration, the only zone selectivity activation
event is the one set and standard selectivity operation is therefore not active
(changes should only be made by expert technical personnel).