Siemens SIPROTEC

Functions
2.24 Monitoring Functions
SIPROTEC, 7SD5, Manual
C53000-G1176-C169-5, Release date 02.2011
434
1)
After three unsuccessful restart attempts, the device is shut down.
2)
DOK = „Device Okay“ = Break contact of the readiness relay = Life contact
Voltage failure, 3-phase
„Fuse Failure Monitor“
External
(power system or connection)
Indication
Distance protection
blocked,
Undervoltage protection
blocked,
Weak-infeed tripping
blocked,
Frequency protection
blocked and
Direction determination
of the earth fault protec-
tion blocked
„VT FuseFail>10s“
(169),
„VT FuseFail“ (170)
As allocated
Voltage failure, sin-
gle/two-phase
„Fuse Failure Monitor“
External
(voltage transformers)
Indication
Distance protection
blocked
Undervoltage protection
blocked,
Weak-infeed tripping
blocked,
Frequency protection
blocked and
Direction determination
of the earth fault protec-
tion blocked
„VT FuseFail>10s“
(169),
„VT FuseFail“ (170)
As allocated
Voltage failure,
three-phase
External
(power system or connection)
Indication
Distance protection
blocked,
Undervoltage protection
blocked,
Weak-infeed tripping
blocked,
Frequency protection
blocked and
Direction determination
of the earth fault protec-
tion blocked
„Fail U absent“ (168) As allocated
Trip circuit supervision External
(trip circuit or control voltage)
Indication „FAIL: Trip cir.“ (6865) As allocated
Monitoring Possible Causes Malfunction Re-
sponse
Indication (No.) Output