GE C70 Instruction Manual page 411

6 ACTUAL VALUES
MESSAGE
MESSAGE
MESSAGE
MESSAGE
MESSAGE
The metered values for real, reactive, and apparent power, as well as power factor, are displayed in this menu. The "SRC
1" text is replaced by whatever name was programmed by the user for the associated source (see
 ).
SETUP SIGNAL SOURCES
When VTs are configured in wye, the C70 calculates power in each phase and three-phase power is measured as
When VTs are configured in delta, the C70 does not calculate power in each phase and three-phase power is measured as
where
S is the apparent power
V , V , V , I , I , I are phase voltage and phase current phasors
A B C A B C
V and V are phase-to-phase voltage phasors
AB CB
Î is the conjugate of I
g) FREQUENCY METERING

PATH: ACTUAL VALUES METERING
 FREQUENCY
 SRC 1
The metered frequency values are displayed in this menu. The "SRC 1" text will be replaced by whatever name was pro-
grammed by the user for the associated source (see
is measured via software-implemented zero-crossing detection of an AC signal. The signal is either a
SOURCE FREQUENCY
Clarke transformation of three-phase voltages or currents, auxiliary voltage, or ground current as per source configuration
(see the 
SYSTEM SETUP
final frequency measurement is passed through a validation filter that eliminates false readings due to signal distortions and
transients.
GE Multilin
SRC 1 APPARENT PWR
φc:
0.000 VA
SRC 1 POWER FACTOR
3φ: 1.000
SRC 1 POWER FACTOR
φa:
1.000
SRC 1 POWER FACTOR
φb:
1.000
SRC 1 POWER FACTOR
φc:
1.000
S = V x Î + V
A A B
S = V x Î
AB A
 
SOURCE SRC 1
SRC 1 FREQUENCY:
0.00 Hz
SETTINGS
settings). The signal used for frequency estimation is low-pass filtered. The
POWER SYSTEM
C70 Capacitor Bank Protection and Control System
x Î + V x Î
B C C
+ V x Î
CB C
FREQUENCY
 
SYSTEM SETUP SIGNAL SOURCES
6.3 METERING

SETTINGS SYSTEM
(EQ 6.1)
(EQ 6.2)
6
).
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