ABB RES670 Technical Manual page 212

Section 8
Current protection
206
Characteristic
for PUREV
-RCA +85 deg
RCA -85 deg
Characteristic for forward
release of measuring steps
ANSI11000243 V1 EN-US
Figure 60: Operating characteristic for ground-fault directional element using the
zero sequence components
The relevant setting parameters for the directional supervision element are:
• The directional element will be internally enabled to trip as soon as Iop is bigger
than 40% of IDirPU and the directional condition is fulfilled in the set direction.
• The relay characteristic angle AngleRCA, which defines the position of forward
and reverse areas in the operating characteristic.
The directional comparison will set the output binary signals:
1. PUFW=1 when operating quantity magnitude Iop x cos(φ - AngleRCA) is bigger
than setting parameter IDirPU and directional supervision element detects fault in
forward direction.
2. PUREV=1 when operating quantity magnitude Iop x cos(φ - AngleRCA) is bigger
than 60% of setting parameter IDirPU and directional supervision element detects
fault in reverse direction.
Operating area
PUREV
0.6 * INDirPU
Characteristic for reverse
release of measuring steps
40% of
INDirPU
RCA
65°
I = 3I
op
Operating area
Characteristic
for PUFW
1MRK 511 408-UUS A
-RCA -85 deg
VPol = -3V
INDirPU
PUFW
0
ANSI11000243-1-en.ai
Phasor measurement unit RES670 2.2 ANSI
Technical manual
RCA +85 deg
0