ABB REG650 - Basic Operation Characteristics

R
jx
Mho, zone3
Mho, zone2
Mho, zone1
IEC09000172_1_en.vsd
IEC09000172 V1 EN
Figure 67: Mho, offset mho characteristic
Zone 3 can be equipped with a load encroachment function which cuts off a section of
the characteristic when enabled. The function is activated by setting the parameter
LoadEnchModZ3 to On. Enabling of the load encroachment function increases the
possibility to detect high resistive faults without interfering with the load impedance.
The algorithm for the load encroachment is located in the Load encroachment
(LEPDIS) function, where the relevant settings can be found. Information about load
encroachment from LEPDIS function to zone measurement is sent via the input signal
LDCND in binary format.
7.2.6.3 Basic operation characteristics
Each impedance zone can be enabled and disabled by setting OpModeZx (where x is
1-3 depending on selected zone).
The zone reach for phase-to-phase fault is set individually in polar coordinates. The
impedance is set by the parameter ZxFwd and ZxRev and the corresponding arguments
by the parameter ImpedanceAng. The setting ImpedanceAng is common for all three
zones.
Section 7 1MRK 502 048-UEN A
Impedance protection
150
Technical manual