ABB ret650 - Simplified Logic Diagrams; Technical Data

7.3.6.2 Simplified logic diagrams
Figure 61 schematically presents the creation of the phase-to-phase operating
conditions.
IEC10000226-1-en.vsd
&
&
t
10 ms
t
20 ms
&
Bool to
integer
STCNDLE
BLOCK
&
Block
03 0.1I <
03 0.4 phmaxI I< ×
&
OR
03 0.05I ³
03 0.2 phmaxI I³ ×
R
X
L1
L1L2
&
IEC10000226 V1 EN
Figure 61: Phase-to-phase L1L2 operating conditions (residual current criteria)
Special attention is paid to correct phase selection at evolving faults. A STCNDLE
output signal is created as a combination of the load encroachment characteristic and
current criteria, refer to figure 61. This signal can be configured to STCND functional
input signals of the distance protection zone and this way influence the operation of
the phase-to-phase zone measuring elements and their phase related starting and
tripping signals.
7.3.7 Technical data
Table 65: LEPDIS technical data
Function
Range or value Accuracy
Load encroachment criteria:
Load resistance, forward and
reverse
Safety load impedance angle
(1.00–3000.00) Ω/phase
(5-85) degrees
± 5.0% static accuracy
± 2.0 degrees static angular
accuracy
Conditions:
Voltage range: (0.1-1.1) x U
r
Current range: (0.5-30) x I
r
Reset ratio
105% typically -
Section 7 1MRK 504 135-UEN A
Impedance protection
140
Technical manual