12.4.3.1
Phase-to-phase faults
M14944-292 v8
ZAngPP
ZPP
1
2
3
Ohm/phase
R
X
IEC07000009-4-en.vsd
50%
IEC07000009 V4 EN-US
Figure 37: Proposed test points for phase-to-phase fault
Table 21: Test points for phase-to-phase (ohms / phase)
Test
points
reach
Value
Comments
1
X
ZPP · sin(ZAngPP)
R
ZPP · sin(ZAngPP)
2
X
0,5· (ZPP· sin(ZAngPP)
R
0,5·ZPP + ΔR = 0,5·ZPP·(1+cos(ZAngPP))
3
X
0,5·ZPP·sin(ZAngPP)
R
0,5·ZPP - ΔR = 0,5·ZPP(1-cos(ZAngPP))
Change the magnitude and angle of phase-to-phase voltage to achieve impedances at test
points 1, 2 and 3. For each test point, observe that the output signals, START, STLx and STPP
are activated where x refers to the actual phase to be tested. After the timer
tPP for the actual
zone has elapsed, also the signals TRIP, TRPP and TRx shall be activated.
12.4.3.2
Phase-to-earth faults
M14944-393 v7
For simplicity, the same test points as for phase-to-phase faults are proposed, but
considering new impedance values.
Section 12
1MRK 502 067-UEN B
Testing functionality by secondary injection
110
Commissioning manual
