ABB Relion 670 series - Page 708

V=-3V0
Ipickup
Operate region
I=3Io
mta line
RCADir
ROADir
en05000252_anis.vsd
IEC05000252-ANIS V1 EN-US
Figure 371: 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 trip angle,
ROADir parameter setting; see figure 371).
V=-3V0
Operate region
RCADir
ROADir
Ipickup
I=3Io
mta line
F
en05000253_ansi.vsd
ANSI05000253 V1 EN-US
Figure 372: CVGAPC, IcosPhi&V directional operating principle
where:
RCADir is 75°
ROADir is 50°
Section 11 1MRK 502 066-UUS B
Multipurpose protection
702
Technical manual