Figure 217: Epatr B Characteristic Shown For Tms = 1.0; Figure 218: Sensitive Earth Fault Protection Logic Diagram - GE MiCOM P40 Agile Technical Manual

Chapter 13 - Current Protection Functions
1000
100
10
1
0.1
V00616

Figure 217: EPATR B characteristic shown for TMS = 1.0

5.3 SENSITIVE EARTH FAULT PROTECTION LOGIC
IN
ISEF>1 Current
928
CTS Block
1724
Inhibit ISEF>1
ISEF>1 Direction
VN
ISEF> VNpol Set
IN
Low Current
Residual voltage polarisation
833
VTS Slow Block
ISEF> Blocking
VTS Blocks IN>1
409
ISEF>1 Timer Blk
ISEF> Blocking
*
AR Blks ISEF>3
V00738

Figure 218: Sensitive Earth Fault Protection logic diagram

378
1
Current in Primary A (CT Ratio 100A/1A)
&
Directional
check
&
* Stages 3 and 4 only
EPATR Curve
10
& &
100 1000
777
IDMT/ DT
671
Note: For the purpose of clarity , this diagram shows the first
relevant stage number for each signal and setting name .
P54x1i-TM-EN-1
P543i/P545i
IN>1 Start
IN>1 Trip