⎯
125
⎯
6
F
2
S
0
8
3
5
k0 = 20% of rated current
The CT circuit current monitoring allows high sensitivity detection of failures that have occurred
in the AC input circuit. This monitoring can be disabled by the scheme switch [CTSV].
3.3.4 CT Circuit Failure Detection
If a failure occurs in a CT circuit, the differential elements may operate incorrectly. GRL100
incorporates a CT failure detection function (CTF) against such incorrect operation. When the
CTF detects a CT circuit failure, it can block the DIF trip.
The CTF is enabled or disabled by the scheme switch [CTFEN] as follows:
-
“Off”: Disabled.
-
“On”: Enabled. If once CTF is detected, the CTF function cannot be reset until ID is
reset.
-
“OPT-On”: Enabled. After CTF is detected, the CTF function is reset if CTFUV,
CTFDV or CTFOVG operates.
The DIF trip is blocked or not by the scheme switch [CTFCNT].
-
“NA”: No block the DIF trip
-
“BLK”: Block the DIF trip
Detection logic
Figure 3.3.4.1 shows the CTF detection logic.
&
CTFID
CTFUV
CTFUVD
CTFOVG
1
≥
1
CTF detection
391:CTFOVG
392:CTFUVD-A
393:CTFUVD-B
394:CTFUVD-C
&
381:CTFID-A
382:CTFID-B
383:CTFID-C
388:CTFUV-A
389:CTFUV-B
390:CTFUV-C
1
CTF detection
CTFID (CFID): Differential current element for CTF
CTFUVD (CFDV): Undervoltage change element for CTF
CTFUV (CFUV): Undervoltage element for CTF
CTFOVG (CFOVG): Zero-sequence overvoltage element for CTF
Figure 3.3.4.1 CTF Detection Logic
Setting
The setting elements necessary for the CTF and their setting ranges are as follows:
Element Range
Step Default Remarks
CFID
0.25 - 5.00 A
0.1 A
0.25 A
Id current level
( 0.05 - 1.00 A
0.01 A
0.05 A) (*)
CFUV
20 - 60 V
1 V
20 V
CFDV
1 - 10 %
1 %
7 %
% of rated voltage
CFOVG
0.1 - 10.0 V
0.1 V
1.0 V
Zero-sequence voltage
[CTFEN]
Off/On/OPT-On
Off
CTF enabled or not
[CTFCNT]
NA / BLK
NA
Control by CTF detection
(*) Current values shown in the parentheses are in the case of 1 A rating. Other current values are in
the case of 5 A rating.
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: ......