ABB Relion 670 series, Technical Reference Manual

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V=-3V0
Ipickup
Operate region
I=3Io
mta line
RCADir
ROADir
en05000252_anis.vsd
IEC05000252-ANIS V1 EN
Figure 288: I & V directional operating principle for CVGAPC function
where:
RCADir is -75°
ROADir is 50°
The second principle, referred to as " IcosPhi&V " in the parameter setting tool, checks
that:
• that the product I·cos(Φ) is bigger than the set pick-up level, where Φ is angle
between the current phasor and the mta line
• that the phasor of the measured current is within the operating region (defined by
the I·cos(Φ) straight line and the relay operate angle,
ROADir parameter setting;
see figure 288 ).
1MRK505222-UUS C
Section 10
Multipurpose protection
573
Technical reference manual