UL1
R1Zx + j X1Zx
IL1
RFPEZx
Phase-to-earth
fault in phase L1
Phase-to-phase
fault in phase
L1-L2
Three-phase
fault or Phase-to-
phase-earth fault
(Arc + tower
resistance)
0
(R0Zx-R1Zx)/3 +
j (X0Zx-X1Zx)/3 )
IN
UL1
R1Zx + j X1Zx
IL1
UL2
R1Zx + j X1Zx
IL2
RFPPZx
UL1
R1Zx + j X1Zx
IL1
UL3
R1Zx + j X1Zx
IL3
0.5·RFPPZx
0.5·RFPPZx
(Arc resistance)
Phase-to-earth
element
Phase-to-phase
element L1-L2
Phase-to-phase
element L1-L3
IEC11000419-3-en.vsdx
IEC11000419 V3 EN-US
Figure 34: Fault loop model
Mho characteristic
GUID-9269239B-3A04-44CD-BE00-FD850D42836B v2
ZMFPDIS implements quadrilateral and mho characteristic in all the six zones
separately. Set OpModePEZx or OpModePPZx setting to Mho or Offset, to choose
a particular measuring loop in a zone to work as mho (or Offset Mho) distance
protection.
Zones 3 to 5 can be selected to be either forward or reverse with positive sequence
polarized mho characteristic; alternatively self polarized offset mho characteristics.
The operating characteristic is in accordance to figure 35 where zone 5 is selected
offset mho.
Section 6 1MRK 506 382-UEN A
Impedance protection
100 Line distance protection REL650 2.2 IEC
Technical manual