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Electric Power Generation
Installation and maintenance
5747 en - 2018.10 / a
Dual plate D700
24
4.4. Anomalies and problems
Several anomalies can occur on the AVR, which may result in it being replaced. These faults are listed in the
table below.
ANOMALIES
CAUSES
REMEDIES
RESTARTING
Loss of sensing fault
Generator sensing VT
broken
Replace the faulty VT
Stop the generator and initialize
plate operation.
AVR internal sensing
circuit broken
Replace the AVR
Restart the plate with the procedure
in section 4.3.5.
AVR power transistor short-
circuited
Component fault or
exciter circuit open
which has generated an
overvoltage on the
transistor
Replace the AVR
Restart the plate with the procedure
in section 4.3.5.
Power supply fault on one
AVR
Power supply fault
Replace the 24 VDC
power supply
Restart the corresponding power
supply and check the functions
work.
AVR internal power
supply fault
Replace the AVR
Restart the plate with the procedure
in section 4.3.5.
Control 24 VDC power
supply fault
Plate general fault
Replace the 24 VDC
power supply
Restart the corresponding power
supply and check the functions
work.
Microcontroller fault on one
AVR
Component failure
Replace the AVR
Restart the plate with the procedure
in section 4.3.5.
The AVR is in "fault" mode
when an attempt is made to
switch it "online"
A condition has not
been met for the AVR
to switch to "online"
mode
Check that the
disconnect terminals are
closed, the connectors
are correctly inserted, the
AVR is supplied with
power and the
measurements comply
with the "active" AVR
Restart the plate with the procedure
in section 4.3.5.
One AVR doesn't change
mode when "maintenance"
is requested
Both AVRs are in
regulation mode and the
"online" one is not marked
"redundancy"
Communication
between the two AVRs
is faulty
Check the serial link
between the two AVRs
Restart the plate with the procedure
in section 4.3.5.