The output PHSCND provides release information from the phase selection part only. DLECND
provides release information from the load encroachment part only. PLECND provides release
information from the phase selection part and the load encroachment part combined, that is, both
parts have to issue a release at the same time (this signal is normally not used in the zone
measuring element). In these signals, each fault type has an associated value, which represents
the corresponding zone measuring loop to be released. The values are presented in table 119.
0= no faulted phases
1= AG
2= BG
3= CG
4= -ABG
5= -BCG
6= -CAG
7= -ABCG
8= -AB
9= -BC
10= -CA
11= ABC
An additional logic is applied to handle the cases when phase-to-ground outputs are to be
asserted when the ground input G is not asserted.
The output signal PLECND is activated when the load encroachment is operating.
PLECNDis connected to the input STCND for selected quadrilateral impedance measuring zones to
be blocked. The signal must be connected to the input LDCND for selected mho impedance
measuring zones .
The load encroachment at the measuring zone must be activated to release the
blocking from the load encroachment function.
7.5.7 Technical data
SEMOD153649-2 v7
Table 120: FMPSPDIS (21) technical data
Function Range or value Accuracy
Load encroachment criteria:
Load resistance, forward and
reverse
(1.00–3000.00) W/phase
(5–70) degrees
±2.0% static accuracy
Conditions:
Voltage range: (0.1–1.1) x V
n
Current range: (0.5–30) x I
n
Angle: at 0 degrees and 85
degrees
1MRK 502 066-UUS B Section 7
Impedance protection
253
Technical manual
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