ABB UNITROL 1020 - Miscellaneous Functions

Chapter 3 - Device Overview 
70 3BHS335648 E82 UNITROL 1020 User Manual
The number of samples is limited to 2000 samples/signal. If the SW-Option is disabled
the recording will be limited to 200 samples/signal.
3.4.4.7 Event Monitor
Events are stored on non-volatile flash and can be read out by MODBUS requests. Event
triggering signals are grouped as follows:
 Generator state changes
 Active Mode changes
 Limiters ON and OFF
 Alarms
 Trips
 Excitation ON (operation mode)
 Parameter change
3.4.5 Miscellaneous Functions
3.4.5.1 History Logger
The History Logger records the last two hours of operation. A measurement sample of 12 defined
signals is stored in the non-volatile flash every minute. Each time the excitation is started the
default values are stored in the log to identify restart conditions.
Table 3-4 Recorded signal of History logger
Signal
Signal identification
Value of start Exc.
Machine voltage
Umrel
0%
Machine current
IM2rel
0%
Reactive power
Qrel
0%
AVR output PWM
PWM
50%
Generator state
GenState
0
AVR Control mode
Generator control mode
0
Machine frequency
fMachine
0Hz
Limiter status
Combined Limit
0
Active Power
Prel
0%
AVR input voltage (rectified)
Upwr
0V
Temperature of controller
Temperature DSP
0°C
3.4.5.2 FCB Control
Field circuit breaker control
FCB Control is an alternative way to control the field circuit breaker. The control is active,
when the FCB command signals are configured.