Setting The Transient Blocking Time (T Transblk); Ct/Vt Inputs Of The Function; Supplementary Information For Binary Inputs - ABB RELION REB500 Technical Manual

1MRK 505 406-UEN B
In a blocking scheme, tripping is delayed by the setting of
protection at the remote end to decide on the direction of the fault and to transmit a
corresponding blocking signal, if necessary.
tWait should be set at least as long as the measuring time (about 30 ms) plus the longest
possible signal transmission time.
5.9.6.10

Setting the transient blocking time (t TransBlk)

The protection function includes a transient blocking logic to prevent any mal-operation
during the course of tripping a fault or autoreclosure on double-circuit lines, when there is a
likelihood of the flow of energy reversing direction. The time setting can be selected in a wide
range to suit the prevailing conditions.
For example, after a fault has been detected in the backwards direction, a second directional
decision in the forwards direction is inhibited for the setting of
The time chosen is determined largely by the time required for the measurement to reset and
the transfer tripping scheme in use.
The recommended setting is 60 ms plus the reset time of the communication channel.
5.9.6.11

CT/VT inputs of the function

Where the zero-sequence components of the voltages and the currents are derived internally,
the CT and VT inputs must be connected precisely as shown in the wiring diagram. The neutral
of the CTs in this case is formed on the line side and the parameter
line side .
5.9.6.12

Supplementary information for binary inputs

Ext Block
Applying a signal to the
Receive
The signal transmitted by the protection at the remote end is connected to this input.
CB closed
The CB closed input is intended for the position indicator signal from the circuit-breaker and
has a fixed pick-up delay of 50 ms. The protection function is only enabled when this signal is
received to confirm that the CB is closed. The corresponding auxiliary contacts for the three
phases must be connected in series to ensure that the protection does not operate during
single-phase reclosure.
The echo logic is enabled 100 ms after the circuit-breaker is opened.
VT Supervision
The VT Superv input is needed to block the echo logic. It can be excited either by the VTSup
signal from the internal distance protection function or an auxiliary contact on the MCB via a
binary input.
If this input is not needed, it must be set to
Bay protection functions REB500
Technical manual
Ext. Block input disables the entire protection function.
F .
© Copyright 2019 ABB. All rights reserved
Bay protection functions
tWait to allow time for the
GUID-4B3A8D0A-C2FF-4303-843F-DCD831178124 v1
t TransBlk .
GUID-E238F9D9-12D1-428D-984B-93F37D0D5173 v1
CT neutral must be set to
GUID-75464C67-88D9-463F-BB75-563F5B765F94 v1
Section 5
167