GE L90 Instruction Manual page 616

METERING
This menu displays metered values for real, reactive, and apparent power, as well as power factor. The "SRC 1" text is
replaced by the name programmed by the user for the associated source (see
).
SOURCES
When VTs are configured in wye, the L90 calculates power in each phase and three-phase power is measured as
When VTs are configured in delta, the L90 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
A B C A B C
V and V are phase-to-phase voltage phasors
AB CB
Î is the conjugate of I
6.4.3.7 Energy metering
ACTUAL VALUES  METERING  SOURCE SRC 1  ENERGY
 ENERGY
 SRC 1
6
This menu displays metered values for real and reactive energy. The "SRC 1" text is replaced by the name programmed by
the user for the associated source (see
accumulated, record them and then reset them immediately prior to changing CT or VT characteristics.
6.4.3.8 Demand metering
ACTUAL VALUES  METERING  SOURCE SRC 1  DEMAND
 DEMAND
 SRC 1
6-20
SRC 1 POWER FACTOR

3φ:
SRC 1 POWER FACTOR

φa:
SRC 1 POWER FACTOR

φb:
SRC 1 POWER FACTOR

φc:
S = V
are phase voltage and phase current phasors
SRC 1 POS WATTHOUR:

0.000 Wh
SRC 1 NEG WATTHOUR:

0.000 Wh
SRC 1 POS VARHOUR:

0.000 varh
SRC 1 NEG VARHOUR:

0.000 varh
SETTINGS  SYSTEM SETUP  SIGNAL SOURCES
SRC 1 DMD IA:

0.000 A
SRC 1 DMD IA MAX:

0.000 A
SRC 1 DMD IA DATE:

2001/07/31 16:30:07
SRC 1 DMD IB:

0.000 A
1.000
1.000
1.000
1.000
x Î + V x Î + V x Î
A A B B C C
S = V x Î + V x Î
AB A CB C
L90 LINE CURRENT DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL
CHAPTER 6: ACTUAL VALUES
SETTINGS  SYSTEM SETUP  SIGNAL
). Because energy values are
Eq. 6-1
Eq. 6-2