Psl For Tcs Scheme 2; Figure 44: Psl For Tcs Scheme 2; Figure 45: Tcs Scheme 3; Figure 46: Psl For Tcs Scheme 3 - GE MiCOM P747 Agile Technical Manual

Chapter 6 - Monitoring and Control
7.2.1

PSL FOR TCS SCHEME 2

Opto-input 1
Opto-input 2
Key: External DDB Signal
Time Delay Inverter

Figure 44: PSL for TCS Scheme 2

The PSL for this TCS scheme 2 is practically the same as that of TCS scheme 1. The main difference is that
both opto-inputs must be low before a trip circuit fail alarm is given.
7.3 TRIP CIRCUIT SUPERVISION SCHEME 3
TCS Scheme 3 is designed to provide supervision of the trip coil with the breaker open or closed, but unlike
TCS schemes 1 and 2, it also provides pre-closing supervision of the trip path. Since only one opto-input is
used, this scheme is not compatible with latched trip contacts. If you require CB status monitoring, further
opto-inputs must be used.
+ve
Output Relay
Opto-input
V01216

Figure 45: TCS Scheme 3

When the CB is closed, supervision current passes through the opto-input, resistor R2 and the trip coil.
When the CB is open, current flows through the opto-input, resistors R1 and R2 (in parallel), resistor R3 and
the trip coil. Unlike schemes 1 and 2, supervision current is maintained through the trip path with the breaker
in either state, therefore providing pre-closing supervision.
7.3.1 PSL FOR TCS SCHEME 3
Opto-input
Key: External DDB Signal
Time Delay Inverter

Figure 46: PSL for TCS Scheme 3

190
0
1 dropoff
400
& OR gate 1
Trip path
R2
R1
0
dropoff
400
&
&
50
&
pickup
0
R3
52A
52B
Circuit Breaker
50
pickup
0
MiCOM P747
CB Aux 3ph (52A)
0
NC Output Relay
straight
0
CB Aux 3ph (52B)
Latching LED
User Alarm
V01218
Trip coil
-ve
0
NC Output Relay
straight
0
Latching LED
User Alarm
V01217
P747-TM-EN-1
P747-TM-EN-1.1