Figure 77: CB Fail Non Current Protection Logic
3.5 COMPOSITE EARTH FAULT START LOGIC
1
IN1>1 Start
V
02004
IN1>2 Start
IN1>3 Start
IN1>4 Start
IN2>1 Start
IN2>2 Start
IN2>3 Start
IN2>4 Start
ISEF>1 Start
ISEF>2 Start
ISEF>3 Start
ISEF>4 Start
Start N
VN>1 Start
VN>2 Start
VN>3 Start
Key: External DDB Signal
&AND gate OR gate 1
Figure 78: Composite Earth Fault Start Logic
3.6 ANY TRIP LOGIC
Trip Command In
V02005
Trip Command Out
Key: External DDB Signal
&AND gate OR gate 1
Figure 79: Any Trip Logic
3.7 SEF ANY START LOGIC
1
V
02006
ISEF1>1 Start
ISEF1>2 Start
ISEF1>3 Start
ISEF1>4 Start
ISEF> Start
Key: External DDB Signal
&AND gate OR gate 1
Figure 80: SEF Any Start Logic
Chapter 12 - Scheme Logic MiCOM P747
320 P747-TM-EN-1