Chapter 6 - Current Protection Functions
For the forward direction, the positive sequence impedance magnitude is compared with a set value, and the
positive sequence impedance angle is compared with two values, which define the angular range. If the criteria
are satisfied and the Blinder mode is in the direction Forward or Both, the blinder signals Z1 FWD Blinder and Z1
LoadBlinder are produced.
For the reverse direction, the positive sequence impedance magnitude is compared with a set value, and the
positive sequence impedance angle is compared with two values, which define the angular range. If the criteria
are satisfied and the Blinder mode is in the direction Forward or Both, the blinder signals Z1 REV Blinder and Z1
LoadBlinder are produced.
Z Angle
FWD Z Angle
X
-1
Z1 Magnitude
FWD Z Impedance
Blinder Mode
Forward
Both
Z Angle
REV Z Angle
-180 °
+180 °
Z Magnitude
REV Z Impedance
Blinder Mode
Reverse
Both
V1
Blinder V< Block
Blinder Status
Enabled
Blinder Function
1 ph(based on Z )
VTS Slow Block
CTS Block
V00651
Figure 80: Load Blinder logic phase A
154
&
1
&
1
&
Pick up
Cycles
&
Drop off
Cycles
Pick up
Cycles
&
Drop off
Cycles
P14x
A FWD Blinder
1
A LoadBlinder
A REV Blinder
P14xEd1-TM-EN-1