Functions
2.14 Monitoring Functions
SIPROTEC, 7SD80, Manual
E50417-G1140-C474-A1, Release date 09.2011
175
Table 2-4
Summary of the Device's Fault Responses
1)
Following three unsuccessful restarting attempts, the device is put out of operation
2)
DOK = „Device OK“ = NC contact of the readiness relay = life contact
Monitoring
Possible causes
Fault response
Indication (no.)
Output
Auxiliary voltage
failure
External (aux. voltage) Inter-
nal (converter)
Device out of operation
All LEDs dark
DOK
drops out
Measured-value ac-
quisition
Internal (converter or refer-
ence voltage)
Protection out of opera-
tion, alarm
ERROR „LED“
„Error A/D-conv.“ (181)
DOK
drops out
Buffer battery
Internal (Buffer battery)
Indication
„Fail Battery“ (177)
As routed
Hardware watchdog Internal (processor failure)
Device out of operation
ERROR „LED“
DOK
drops out
Software watchdog
Internal (program sequence) Restart attempt
ERROR „LED“
DOK
drops out
Working memory
ROM
Internal (RAM)
Restart attempt
, Restart
abort
Device out of operation
LED flashes
DOK
drops out
Program memory
RAM
Internal (EPROM)
Restart attempt
ERROR „LED“
DOK
drops out
Settings memory
Internal (Flash-EPROM or
RAM)
Restart attempt
ERROR „LED“
DOK
drops out
Sampling frequency Internal (clock generator)
Restart attempt
ERROR „LED“
DOK
drops out
Adjustment values
Internal (EEPROM or RAM) Indication:
Using default values
„Alarm adjustm.“ (193)
As routed
Modules
Module does not comply
with order number (MLFB)
Indications:
Protection out of operation
„Error Board 1...5“ (183
... 187)
and if applicable
„Error A/D-conv.“. (181)
DOK
drops out
Current sum
Internal (measured value
acquisition)
Indication
Total blocking of the differ-
ential protection
„Failure
Σ
i“ (289)
As routed
Current symmetry
External (power system or
current transformer)
Indication
„Fail I balance“ (163)
As routed
Broken wire
External (power system or
current transformer)
Indication
Phase-selective blocking
of the differential protec-
tion
„Broken Iwire L1“ (290),
„Broken Iwire L2“ (291),
„Broken Iwire L3“ (292)
As routed
Voltage symmetry
External (power system or
voltage transformer)
Indication
„Fail V balance“ (167)
As routed
Voltage phase se-
quence
External (power system or
connection)
Indication
„Fail Ph. Seq.“ (171)
As routed
Voltage failure,
3-phase „Fuse
Failure Monitor“
External (power system or
connection)
Indication
Undervoltage protection
blocked,
Frequency protection
blocked
„VT FuseFail>10s“
(169),
„VT FuseFail“ (170)
As routed
Voltage loss,
„Fuse failure moni-
tor“
External (voltage transform-
ers)
Indication
Undervoltage protection
blocked,
„VT FuseFail>10s“
(169),
„VT FuseFail“ (170)
As routed
Voltage failure,
3-phase
External (power system or
connection)
Indication
Undervoltage protection
blocked,
„Fail V absent“ (168)
As routed
Trip circuit
supervision
External (trip circuit or
control voltage)
Indication
„74TC Trip cir.“ (6865)
As routed