10
CURRENT DIFFERENTIAL PROTECTION
10.1
CURRENT DIFFERENTIAL BIAS CHARACTERISTIC
1.
In the CONFIGURATION column, disable all protection elements other than the one being tested.
2.
Make a note of which elements need to be re-enabled after testing.
3.
Set the device to loopback mode, isolating it from the remote end.
4.
Connect the test circuit shown below. Alternatively, use an injection test set to supply Ia and Ib
V01452
Ra
Rb
P54x IED
Ph a
Ph b
Ia
Ib
A
A
L
N
Figure 206: Current Differential Bias Characteristics
10.1.1
LOWER SLOPE
If three LEDs have been assigned to provide phase segregated trip information (Trip A, Trip B and Trip C), these may
be used to indicate correct operation per-phase. If LEDs are not used, use monitor options, as follows.
1.
Go to COMMISSION TESTS > Monitor Bit. Change cells 1, 2 and 3 to the values 523, 524 and 525 respectively.
The Test Port Status cell then displays the status of Trip Output A (DDB 523), Trip Output B (DDB 524) and
Trip Output C (DDB 525), with the rightmost bit representing Phase A Trip. From now on monitor the Test
Port Status cell.
2.
Make sure that the IED is in loopback mode by setting the Loopback Mode cell to External and applying a
loop-back, either by direct fibre or using a P59x. Alternatively you can set the Test Loopback cell to
Internal
.
3.
Adjust the variac and the resistor to give a bias current of 1pu in the A-phase (1A into terminals 3-2 for 1A
applications, or 5A into terminals 1-2 for 5A applications).
The device trips, contacts associated with the A-phase operate, and bit 1 (rightmost) of the Test Port Status
cell is set to 1. Some LEDs, including the yellow alarm LED, switch OFF, but ignore these for the moment.
4.
When the current in the A Phase is established, close the switch and slowly increase the current in the B
phase from zero until Phase B trips (bit 2 of the Test Port Status cell is set to 1).
For the initial conditions where the magnitude of the bias current in phase A = 1 pu, record the phase B current
magnitude and check that it corresponds to the following.
Connection type
Magnitude of differential current in phase B
2-terminal & dual redundant
0.25 pu +/-10%
3-terminal
0.216 pu +/-10%
Assumption: Is1 = 0.2 pu, k1 = 30%, Is2 = 2.0 pu
For other differential settings or current injected into A phase (Ia), the following formula can be used (enter slope in
pu form, which is. percentage/100):
Connection type
Magnitude of differential current in phase B
2-terminal & dual redundant
0.5 x (Is1 + (Ia x k1)) pu +/- 10%
P54A/B/C/E
Chapter 20 - Commissioning Instructions
P54xMED-TM-EN-1
475
Summary of Contents for P4A
Page 2: ......
Page 20: ...Contents P54A B C E xviii P54xMED TM EN 1 ...
Page 27: ...CHAPTER 1 INTRODUCTION ...
Page 28: ...Chapter 1 Introduction P54A B C E 2 P54xMED TM EN 1 ...
Page 38: ...Chapter 1 Introduction P54A B C E 12 P54xMED TM EN 1 ...
Page 39: ...CHAPTER 2 SAFETY INFORMATION ...
Page 40: ...Chapter 2 Safety Information P54A B C E 14 P54xMED TM EN 1 ...
Page 52: ...Chapter 2 Safety Information P54A B C E 26 P54xMED TM EN 1 ...
Page 53: ...CHAPTER 3 HARDWARE DESIGN ...
Page 54: ...Chapter 3 Hardware Design P54A B C E 28 P54xMED TM EN 1 ...
Page 86: ...Chapter 3 Hardware Design P54A B C E 60 P54xMED TM EN 1 ...
Page 87: ...CHAPTER 4 SOFTWARE DESIGN ...
Page 88: ...Chapter 4 Software Design P54A B C E 62 P54xMED TM EN 1 ...
Page 99: ...CHAPTER 5 CONFIGURATION ...
Page 100: ...Chapter 5 Configuration P54A B C E 74 P54xMED TM EN 1 ...
Page 120: ...Chapter 5 Configuration P54A B C E 94 P54xMED TM EN 1 ...
Page 121: ...CHAPTER 6 CURRENT DIFFERENTIAL PROTECTION ...
Page 122: ...Chapter 6 Current Differential Protection P54A B C E 96 P54xMED TM EN 1 ...
Page 149: ...CHAPTER 7 AUTORECLOSE ...
Page 150: ...Chapter 7 Autoreclose P54A B C E 124 P54xMED TM EN 1 ...
Page 207: ...CHAPTER 8 CB FAIL PROTECTION ...
Page 208: ...Chapter 8 CB Fail Protection P54A B C E 182 P54xMED TM EN 1 ...
Page 219: ...CHAPTER 9 CURRENT PROTECTION FUNCTIONS ...
Page 220: ...Chapter 9 Current Protection Functions P54A B C E 194 P54xMED TM EN 1 ...
Page 244: ...Chapter 9 Current Protection Functions P54A B C E 218 P54xMED TM EN 1 ...
Page 247: ...CHAPTER 10 VOLTAGE PROTECTION FUNCTIONS ...
Page 248: ...Chapter 10 Voltage Protection Functions P54A B C E 222 P54xMED TM EN 1 ...
Page 261: ...CHAPTER 11 FREQUENCY PROTECTION FUNCTIONS ...
Page 262: ...Chapter 11 Frequency Protection Functions P54A B C E 236 P54xMED TM EN 1 ...
Page 268: ...Chapter 11 Frequency Protection Functions P54A B C E 242 P54xMED TM EN 1 ...
Page 269: ...CHAPTER 12 MONITORING AND CONTROL ...
Page 270: ...Chapter 12 Monitoring and Control P54A B C E 244 P54xMED TM EN 1 ...
Page 300: ...Chapter 12 Monitoring and Control P54A B C E 274 P54xMED TM EN 1 ...
Page 301: ...CHAPTER 13 SUPERVISION ...
Page 302: ...Chapter 13 Supervision P54A B C E 276 P54xMED TM EN 1 ...
Page 312: ...Chapter 13 Supervision P54A B C E 286 P54xMED TM EN 1 ...
Page 323: ...CHAPTER 14 DIGITAL I O AND PSL CONFIGURATION ...
Page 324: ...Chapter 14 Digital I O and PSL Configuration P54A B C E 298 P54xMED TM EN 1 ...
Page 336: ...Chapter 14 Digital I O and PSL Configuration P54A B C E 310 P54xMED TM EN 1 ...
Page 337: ...CHAPTER 15 FIBRE TELEPROTECTION ...
Page 338: ...Chapter 15 Fibre Teleprotection P54A B C E 312 P54xMED TM EN 1 ...
Page 354: ...Chapter 15 Fibre Teleprotection P54A B C E 328 P54xMED TM EN 1 ...
Page 355: ...CHAPTER 16 ELECTRICAL TELEPROTECTION ...
Page 356: ...Chapter 16 Electrical Teleprotection P54A B C E 330 P54xMED TM EN 1 ...
Page 366: ...Chapter 16 Electrical Teleprotection P54A B C E 340 P54xMED TM EN 1 ...
Page 367: ...CHAPTER 17 COMMUNICATIONS ...
Page 368: ...Chapter 17 Communications P54A B C E 342 P54xMED TM EN 1 ...
Page 439: ...CHAPTER 18 CYBER SECURITY ...
Page 440: ...Chapter 18 Cyber Security P54A B C E 414 P54xMED TM EN 1 ...
Page 457: ...CHAPTER 19 INSTALLATION ...
Page 458: ...Chapter 19 Installation P54A B C E 432 P54xMED TM EN 1 ...
Page 471: ...CHAPTER 20 COMMISSIONING INSTRUCTIONS ...
Page 472: ...Chapter 20 Commissioning Instructions P54A B C E 446 P54xMED TM EN 1 ...
Page 513: ...CHAPTER 21 MAINTENANCE AND TROUBLESHOOTING ...
Page 514: ...Chapter 21 Maintenance and Troubleshooting P54A B C E 488 P54xMED TM EN 1 ...
Page 530: ...Chapter 21 Maintenance and Troubleshooting P54A B C E 504 P54xMED TM EN 1 ...
Page 531: ...CHAPTER 22 TECHNICAL SPECIFICATIONS ...
Page 532: ...Chapter 22 Technical Specifications P54A B C E 506 P54xMED TM EN 1 ...
Page 558: ...Chapter 22 Technical Specifications P54A B C E 532 P54xMED TM EN 1 ...
Page 559: ...APPENDIX A ORDERING OPTIONS ...
Page 560: ...Appendix A Ordering Options P54A B C E P54xMED TM EN 1 ...
Page 565: ...APPENDIX B SETTINGS AND SIGNALS ...
Page 566: ...Appendix B Settings and Signals P54A B C E P54xMED TM EN 1 ...
Page 790: ...Appendix B Settings and Signals P54A B C E B224 P54xMED TM EN 1 ...
Page 835: ...APPENDIX C WIRING DIAGRAMS ...
Page 836: ...Appendix C Wiring Diagrams P54A B C E P54xMED TM EN 1 ...
Page 849: ......