4
TRIP CIRCUIT SUPERVISION
In most protection schemes, the trip circuit extends beyond the IED enclosure and passes through components
such as links, relay contacts, auxiliary switches and other terminal boards. Such complex arrangements may
require dedicated schemes for their supervision.
There are two distinctly separate parts to the trip circuit; the trip path, and the trip coil. The trip path is the path
between the IED enclosure and the CB cubicle. This path contains ancillary components such as cables, fuses and
connectors. A break in this path is possible, so it is desirable to supervise this trip path and to raise an alarm if a
break should appear in this path.
The trip coil itself is also part of the overall trip circuit, and it is also possible for the trip coil to develop an open-
circuit fault.
This product supports a number of trip circuit supervision (TCS) schemes.
4.1
TRIP CIRCUIT SUPERVISION SCHEME 1
This scheme provides supervision of the trip coil with the CB open or closed, however, it does not provide
supervision of the trip path whilst the breaker is open. The CB status can be monitored when a self-reset trip
contact is used. However, this scheme is incompatible with latched trip contacts, as a latched contact will short out
the opto-input for a time exceeding the recommended Delayed Drop-off (DDO) timer setting of 400 ms, and
therefore does not support CB status monitoring. If you require CB status monitoring, further opto-inputs must be
used.
Note:
A 52a CB auxiliary contact follows the CB position. A 52b auxiliary contact is the opposite.
V01214
52A
52B
R1
Trip Output Relay
+ve
-ve
Opto-input
Blocking diode
Circuit Breaker
Trip coil
Trip path
Figure 135: TCS Scheme 1
When the CB is closed, supervision current passes through the opto-input, blocking diode and trip coil. When the
CB is open, supervision current flows through the opto-input and into the trip coil via the 52b auxiliary contact.
This means that Trip Coil supervision is provided when the CB is either closed or open, however Trip Path
supervision is only provided when the CB is closed. No supervision of the trip path is provided whilst the CB is open
(pre-closing supervision). Any fault in the trip path will only be detected on CB closing, after a 400 ms delay.
4.1.1
RESISTOR VALUES
The supervision current is a lot less than the current required by the trip coil to trip a CB. The opto-input limits this
supervision current to less than 10 mA. If the opto-input were to be short-circuited however, it could be possible for
the supervision current to reach a level that could trip the CB. For this reason, a resistor R1 is often used to limit the
current in the event of a short-circuited opto-input. This limits the current to less than 60mA. The table below
shows the appropriate resistor value and voltage setting for this scheme.
Trip Circuit Voltage
Opto Voltage Setting with R1 Fitted
Resistor R1 (ohms)
48/54
24/27
1.2k
Chapter 14 - Supervision
P64x
294
P64x-TM-EN-1.3
Summary of Contents for P642
Page 2: ......
Page 18: ...Contents P64x xvi P64x TM EN 1 3 ...
Page 24: ...Table of Figures P64x xxii P64x TM EN 1 3 ...
Page 25: ...CHAPTER 1 INTRODUCTION ...
Page 26: ...Chapter 1 Introduction P64x 2 P64x TM EN 1 3 ...
Page 36: ...Chapter 1 Introduction P64x 12 P64x TM EN 1 3 ...
Page 37: ...CHAPTER 2 SAFETY INFORMATION ...
Page 38: ...Chapter 2 Safety Information P64x 14 P64x TM EN 1 3 ...
Page 50: ...Chapter 2 Safety Information P64x 26 P64x TM EN 1 3 ...
Page 51: ...CHAPTER 3 HARDWARE DESIGN ...
Page 52: ...Chapter 3 Hardware Design P64x 28 P64x TM EN 1 3 ...
Page 87: ...CHAPTER 4 SOFTWARE DESIGN ...
Page 88: ...Chapter 4 Software Design P64x 64 P64x TM EN 1 3 ...
Page 98: ...Chapter 4 Software Design P64x 74 P64x TM EN 1 3 ...
Page 99: ...CHAPTER 5 CONFIGURATION ...
Page 100: ...Chapter 5 Configuration P64x 76 P64x TM EN 1 3 ...
Page 121: ...CHAPTER 6 TRANSFORMER DIFFERENTIAL PROTECTION ...
Page 122: ...Chapter 6 Transformer Differential Protection P64x 98 P64x TM EN 1 3 ...
Page 165: ...CHAPTER 7 TRANSFORMER CONDITION MONITORING ...
Page 166: ...Chapter 7 Transformer Condition Monitoring P64x 142 P64x TM EN 1 3 ...
Page 189: ...CHAPTER 8 RESTRICTED EARTH FAULT PROTECTION ...
Page 190: ...Chapter 8 Restricted Earth Fault Protection P64x 166 P64x TM EN 1 3 ...
Page 215: ...CHAPTER 9 CURRENT PROTECTION FUNCTIONS ...
Page 216: ...Chapter 9 Current Protection Functions P64x 192 P64x TM EN 1 3 ...
Page 249: ...CHAPTER 10 CB FAIL PROTECTION ...
Page 250: ...Chapter 10 CB Fail Protection P64x 226 P64x TM EN 1 3 ...
Page 259: ...CHAPTER 11 VOLTAGE PROTECTION FUNCTIONS ...
Page 260: ...Chapter 11 Voltage Protection Functions P64x 236 P64x TM EN 1 3 ...
Page 274: ...Chapter 11 Voltage Protection Functions P64x 250 P64x TM EN 1 3 ...
Page 275: ...CHAPTER 12 FREQUENCY PROTECTION FUNCTIONS ...
Page 276: ...Chapter 12 Frequency Protection Functions P64x 252 P64x TM EN 1 3 ...
Page 286: ...Chapter 12 Frequency Protection Functions P64x 262 P64x TM EN 1 3 ...
Page 287: ...CHAPTER 13 MONITORING AND CONTROL ...
Page 288: ...Chapter 13 Monitoring and Control P64x 264 P64x TM EN 1 3 ...
Page 306: ...Chapter 13 Monitoring and Control P64x 282 P64x TM EN 1 3 ...
Page 307: ...CHAPTER 14 SUPERVISION ...
Page 308: ...Chapter 14 Supervision P64x 284 P64x TM EN 1 3 ...
Page 322: ...Chapter 14 Supervision P64x 298 P64x TM EN 1 3 ...
Page 323: ...CHAPTER 15 DIGITAL I O AND PSL CONFIGURATION ...
Page 324: ...Chapter 15 Digital I O and PSL Configuration P64x 300 P64x TM EN 1 3 ...
Page 336: ...Chapter 15 Digital I O and PSL Configuration P64x 312 P64x TM EN 1 3 ...
Page 337: ...CHAPTER 16 COMMUNICATIONS ...
Page 338: ...Chapter 16 Communications P64x 314 P64x TM EN 1 3 ...
Page 397: ...CHAPTER 17 CYBER SECURITY ...
Page 398: ...Chapter 17 Cyber Security P64x 374 P64x TM EN 1 3 ...
Page 415: ...CHAPTER 18 INSTALLATION ...
Page 416: ...Chapter 18 Installation P64x 392 P64x TM EN 1 3 ...
Page 431: ...CHAPTER 19 COMMISSIONING INSTRUCTIONS ...
Page 432: ...Chapter 19 Commissioning Instructions P64x 408 P64x TM EN 1 3 ...
Page 460: ...Chapter 19 Commissioning Instructions P64x 436 P64x TM EN 1 3 ...
Page 461: ...CHAPTER 20 MAINTENANCE AND TROUBLESHOOTING ...
Page 462: ...Chapter 20 Maintenance and Troubleshooting P64x 438 P64x TM EN 1 3 ...
Page 477: ...CHAPTER 21 TECHNICAL SPECIFICATIONS ...
Page 478: ...Chapter 21 Technical Specifications P64x 454 P64x TM EN 1 3 ...
Page 507: ...APPENDIX A ORDERING OPTIONS ...
Page 508: ...Appendix A Ordering Options P64x P64x TM EN 1 3 ...
Page 512: ...Appendix A Ordering Options P64x A4 P64x TM EN 1 3 ...
Page 513: ...APPENDIX B SETTINGS AND SIGNALS ...
Page 515: ...APPENDIX C WIRING DIAGRAMS ...
Page 516: ...Appendix C Wiring Diagrams P64x P64x TM EN 1 3 ...
Page 590: ......
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