⎯
41
⎯
6
F
2
S
0
8
3
5
2.3 Overcurrent Backup Protection
Inverse time and definite time overcurrent protections are provided for phase faults and earth
faults respectively.
Scheme logic
The scheme logic of the overcurrent backup protection is shown in Figure 2.3.1. The overcurrent
protection issues single-phase tripping signals in the operation of OC and OCI, and issues a
three-phase tripping signal BU-TRIP in the operation of EF or EFI element. Three-phase
tripping of OC and OCI is available by PLC signals OC_3PTP and OCI_3PTP. Tripping by each
element can be disabled by the scheme switches [OCBT], [OCIBT], [EFBT] and [EFIBT]. The
EF element issues an alarm for the backup trip for earth fault. The alarm can be disabled by the
scheme switch [EFBTAL].
The overcurrent backup protection can be blocked by the binary input signal BUT_BLOCK.
Tripping by each protection can be blocked by PLC signals OC_BLOCK, OCI_BLOCK,
EF_BLOCK and EFI_BLOCK. The OC and EF can trip instantaneously by PLC signals
OC_INST_TP and EF_INST_TP.
BU-TRIP
0.00 – 10.00s
TOC
OC-A
≥
1
&
≥
1
EF
&
t
0
t
0
t
0
"ON"
[OCBT]
+
1
OC_BLOCK
1589
&
&
&
&
"ON"
[OCBIT]
+
1
OCI_BLOCK
1590
&
&
TEF
t
0
0.00 – 10.00s
&
"ON"
[EFBT]
+
"ON"
[EFBTAL]
+
&
&
1
EF_BLOCK
1591
&
EFI
&
"ON"
[EFIBT]
+
&
1
EFI_BLOCK
1592
1
BUT_BLOCK
1550
65
66
67
68
69
70
71
72
OC_TRIP
EF TRIP
EFI TRIP
EFBT (Alarm)
113
118
115
116
117
OC_INST_TP
1633
EF_INST_TP
1634
OC-A TP
OC-B TP
OC-C TP
≥
1
≥
1
≥
1
OC_3PTP
1650
&
461
460
459
OC-A TRIP
OC-B TRIP
OC-C TRIP
≥
1
OCI_TRIP
114
OCI-A TP
OCI-B TP
OCI-C TP
≥
1
≥
1
≥
1
OCI_3PTP
1651
&
464
463
462
OCI-A TRIP
OCI-B TRIP
OCI-C TRIP
OC-B
OC-C
OCI-A
OCI-B
OCI-C
Figure 2.3.1 Overcurrent Backup Protection
Summary of Contents for GRL100-101A
Page 223: ... 222 6 F 2 S 0 8 3 5 ...
Page 228: ... 227 6 F 2 S 0 8 3 5 Appendix B Signal List ...
Page 256: ... 255 6 F 2 S 0 8 3 5 Appendix C Variable Timer List ...
Page 258: ... 257 6 F 2 S 0 8 3 5 Appendix D Binary Output Default Setting List ...
Page 269: ... 268 6 F 2 S 0 8 3 5 ...
Page 270: ... 269 6 F 2 S 0 8 3 5 Appendix E Details of Relay Menu ...
Page 279: ... 278 6 F 2 S 0 8 3 5 ...
Page 288: ... 287 6 F 2 S 0 8 3 5 Appendix G Typical External Connection ...
Page 326: ... 325 6 F 2 S 0 8 3 5 Appendix J Return Repair Form ...
Page 330: ... 329 6 F 2 S 0 8 3 5 Customer Name Company Name Address Telephone No Facsimile No Signature ...
Page 331: ... 330 6 F 2 S 0 8 3 5 ...
Page 332: ... 331 6 F 2 S 0 8 3 5 Appendix K Technical Data ...
Page 343: ... 342 6 F 2 S 0 8 3 5 ...
Page 344: ... 343 6 F 2 S 0 8 3 5 Appendix L Symbols Used in Scheme Logic ...
Page 347: ... 346 6 F 2 S 0 8 3 5 ...
Page 348: ... 347 6 F 2 S 0 8 3 5 Appendix M Multi phase Autoreclose ...
Page 351: ... 350 6 F 2 S 0 8 3 5 ...
Page 352: ... 351 6 F 2 S 0 8 3 5 Appendix N Data Transmission Format ...
Page 358: ... 357 6 F 2 S 0 8 3 5 Appendix O Example of DIF and DIFG Setting ...
Page 364: ... 363 6 F 2 S 0 8 3 5 Appendix Q IEC60870 5 103 Interoperability ...
Page 377: ... 376 6 F 2 S 0 8 3 5 ...
Page 378: ... 377 6 F 2 S 0 8 3 5 Appendix R Failed Module Tracing and Replacement ...
Page 384: ... 383 6 F 2 S 0 8 3 5 Appendix S PLC Setting Sample ...
Page 386: ... 385 6 F 2 S 0 8 3 5 Appendix T Ordering ...
Page 392: ......