ABB RET670 - Introduction; Introduction to the operators manual

Load drop compensation function, LDC.......................................... 287
Voltage control of Parallel Transformers......................................... 289
Minimum Circulating Current (MCC) method...................................289
Master Follower (MF) method..........................................................291
Completing the test..........................................................................292
Section 13 Checking the directionality................................................ 293
Overview...............................................................................................293
Testing the directionality of the distance protection..............................293
Section 14 Commissioning and maintenance of the fault
clearing system................................................................. 297
Commissioning tests.............................................................................297
Periodic maintenance tests...................................................................297
Visual inspection..............................................................................298
Maintenance tests........................................................................... 298
Preparation................................................................................. 299
Recording................................................................................... 299
Secondary injection.................................................................... 299
Alarm test................................................................................... 299
Self supervision check................................................................300
Trip circuit check.........................................................................300
Measurement of service currents............................................... 300
Restoring.................................................................................... 301
Section 15 Troubleshooting.................................................................303
Checking the self supervision signals...................................................303
Checking the self supervision function............................................ 303
Determine the cause of an internal failure..................................303
Self supervision HMI data................................................................303
General IED status..................................................................... 303
Fault tracing.......................................................................................... 304
Internal fault indications...................................................................304
Using front-connected PC............................................................... 305
Diagnosing the IED status via the LHMI hint menu......................... 307
Repair instruction..................................................................................309
Repair support...................................................................................... 310
Maintenance......................................................................................... 310
Section 16 Glossary............................................................................ 311
Table of contents
Transformer protection RET670 2.2 ANSI 11
Commissioning manual