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Electric Power Generation
Installation and maintenance
5747 en - 2018.10 / a
Dual plate D700
19
An "active" AVR can then be switched to an "online" AVR:
Note: The "active" AVR cannot be set to "maintenance" mode if regulation is occurring and the
second AVR is in "maintenance" or "fault" mode.
4.3.2. Correction of setpoints with digital inputs
Setpoint corrections are only copied from the "active" AVR to the "online" AVR by the serial link if they have
been created with digital inputs. The regulation context is then preserved in the event of switching.
4.3.3. Follower
The correction value of the field current given by the follower is copied from the "active" AVR to the
"online" AVR by the serial link. The regulation context is then preserved in the event of switching and running
in manual mode.
4.3.4. Switching on a fault
Several faults can cause switching from the "active" AVR to the "online" AVR:
•
Loss of the AVR internal or 24 VDC power supply
•
A controller fault on the power transistor
•
Loss of sensing on the "active" AVR and not on the "online" AVR
•
A reactive power inversion fault
Start
AVR 1 = active
AVR 2 = online
AVR 1 = maintenance
AVR 2 = active
Contact closed on terminals
XC1.-XC.2
Contact open on terminals
XC.2 – XC.3
Contact open on terminals
XC1.-XC.2
Contact closed on terminals
XC.2 – XC.3
AVR 1 = online
AVR 2 = active
Start
AVR 1 = online
AVR 2 = active
AVR 1 = active
AVR 2 = maintenance
Contact closed on terminals
XC4.-XC.5
Contact open on terminals
XC.5 – XC.6
Contact open on terminals
XC4.-XC.5
Contact closed on terminals
XC.5 – XC.6
AVR 1 = active
AVR 2 = online