ABB RED670 Commissioning Manual page 268

Section 11
Testing functionality by secondary injection
Where:
p
Z
X0
X1
XM
11.13.14.3 Two ended fault locator
The two ended fault locator requires two RED670 IEDs at the local and remote ends, which are
connected through LDCM 2Mbps communication to transmit and receive the signals. The signals
transmitted through the LDCM should be of primary values.
The samples taken from both stations must be absolutely time synchronized. Check for the time
synchronization using the disturbance records from IEDs located at local and remote stations.
Check the function settings related to LDCM, TRM, disturbance record and SMTRFLO for the correct
operation of two ended method and ensure synchronization of the samples.
LDCM
(2Mbps)
RED670
Substation A
IEC17000240 V1 EN-US
Figure 56:
Table 48:
Parameter
Healthy condition
Impedance
magnitude
p = the per unit distance of line length
262
= The expected value of a distance to fault in percent
= Set test point on the test set
x
= Set zero-sequence reactance of a line
= Set positive-sequence reactance of a line
= Set mutual zero-sequence impedance of a line
Overview of IED set up for two ended fault location
Test settings
Local side
U = 63.5V, I = 0 A (balanced
condition)
Test points
• Z = p*((R0 + 2*R1) + j*
d
(X0+2*X1)) for single
phase to ground faults
• Z = p*(R1 + j* X1) for
1-d
three and two phase
faults
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GPS
LDCM
(2Mbps)
RED670
Substation B
IEC17000240-1-en.vsdx
Remote side
U = 63.5V, I = 0 A (balanced
condition)
Test points
• Z = (1-p)*((R0 + 2*R1) +
1-d
j* (X0+2*X1)) for single
phase to ground faults
• Z = (1-p)*(R1 + j* X1) for
1-d
three and two phase faults
1MRK 505 378-UUS Rev. J
GUID-3C4909B4-C3A8-4697-A202-6E4E92E0A0B8 v2
Line differential protection RED670
Commissioning manual