Resistor Values; Psl For Tcs Scheme 3; Trip Circuit Supervision Scheme; Figure 173: Tcs Scheme 3 - GE MiCOM P40 Agile Technical Manual

Chapter 15 - Supervision
+ve
Output Relay
Opto-input
V01216

Figure 173: 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. The
supervision current is maintained through the trip path with the breaker in either state, therefore providing pre-
closing supervision.
5.3.1

RESISTOR VALUES

As with TCS schemes 1 and 2, resistors R1 and R2 are used to prevent false tripping, if the opto-input is
accidentally shorted. However, unlike the other two schemes, this scheme is dependent on the position and value
of these resistors. Removing them would result in incomplete trip circuit monitoring. The table below shows the
resistor values and voltage settings required for satisfactory operation.
Trip Circuit Voltage
24/27
30/34
48/54
110/125
220/250
Warning:
If your IED has Opto Mode settings (Opto 9 Mode, Opto 10 Mode, Opto 11 Mode) in the
OPTO CONFIG column, these settings MUST be set to TCS.
5.3.2

PSL FOR TCS SCHEME 3

Opto Input
*NC stands for Normally Closed.

Figure 174: PSL for TCS Scheme 3

5.4

TRIP CIRCUIT SUPERVISION SCHEME 4

Scheme 4 is identical to that offered by MVAX31 (a Trip Circuit Supervision relay) and consequently is fully
compliant with ENA Specification H7. To achieve this compliance, there are three settings in the OPTO CONFIG
column. These settings (Opto 9 Mode, Opto 10 Mode and Opto 11 Mode) must be set to TCS before the scheme
can be used. Typically only two of these three opto-inputs would be used.
324
Trip path
R2
R1
Resistor R1 and R2
620 Ohms at 2 Watts
820 Ohms at 2 Watts
1.2 kOhms at 5 Watts
2.7 kOhms at 10 Watts
5.2 kOhms at 15 Watts
0
dropoff
400
&
R3
Trip coil
52A
52B
Circuit Breaker
330 Ohms at 5 Watts
430 Ohms at 5 Watts
620 Ohms at 10 Watts
1.5 k Ohms at 15 Watts
2.7 k Ohms at 25 Watts
0
Straight
50
Latching
pickup
0
-ve
Resistor R3
*Output Relay
0
LED
User Alarm
V01217
P14D-TM-EN-8
P14D