Load Blinder Logic; Figure 79: Load Blinder Logic 3Phase - GE MiCOM P40 Agile Technical Manual

P14x
The single phase mode uses the normal impedance (Z) of each phase. When single phase mode is selected, the
overcurrent blocking is phase segregated and is dependant on the individual overcurrent settings per phase. In
single phase mode, only the undervoltage threshold (Blinder V< Block) can block the function.
The three phase mode uses positive sequence impedance (Z1). The three phase mode uses both the negative
sequence overcurrent threshold (Blinder I2>Block) and the undervoltage threshold (Blinder V< Block) to block the
function.
16.2

LOAD BLINDER LOGIC

Z1 Angle
FWD Z Angle
X
-1
Z1 Magnitude
FWD Z Impedance
Blinder Mode
Forward
Both
Z1 Angle
REV Z Angle -180°
+180°
Z1 Magnitude
REV Z Impedance
Blinder Mode
Reverse
Both
V1
Blinder V< Block
I2
Blinder I2<Block
Blinder Status
Enabled
Blinder Function
3ph(based on Z 1)
VTS Slow Block
CTS Block
V00650

Figure 79: Load Blinder logic 3phase

P14xEd1-TM-EN-1
&
1
&
1
&
Chapter 6 - Current Protection Functions
Pick up
Cycles
&
Drop off
Cycles
Pick up
Cycles
&
Drop off
Cycles
Z1 FWD Blinder
1
Z1 LoadBlinder
Z1 REV Blinder
153