GE L30 User Manual

GE Multilin L30 Line Current Differential System 6-19
6 ACTUAL VALUES 6.3 METERING
6
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
SETTINGS  SYSTEM
SETUP
 SIGNAL SOURCES).
When VTs are configured in wye, the L30 calculates power in each phase and three-phase power is measured as
S = V
A
x Î
A
+ V
B
x Î
B
+ V
C
x Î
C
(EQ 6.1)
When VTs are configured in delta, the L30 does not calculate power in each phase and three-phase power is measured as
S = V
AB
x Î
A
+ V
CB
x Î
C
(EQ 6.2)
where
S is the apparent power
V
A
, V
B
, V
C
, I
A
, I
B
, I
C
are phase voltage and phase current phasors
V
AB
and V
CB
are phase-to-phase voltage phasors
Î is the conjugate of I
g) FREQUENCY METERING
PATH: ACTUAL VALUES  METERING  SOURCE SRC 1  FREQUENCY
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
SETTINGS  SYSTEM SETUP  SIGNAL SOURCES).
SOURCE FREQUENCY is measured via software-implemented zero-crossing detection of an AC signal. The signal is either a
Clarke transformation of three-phase voltages or currents, auxiliary voltage, or ground current as per source configuration
(see the
SYSTEM SETUP  POWER SYSTEM settings). The signal used for frequency estimation is low-pass filtered. The
final frequency measurement is passed through a validation filter that eliminates false readings due to signal distortions and
transients.
If the 87L function is enabled, then dedicated 87L frequency tracking is engaged. In this case, the relay uses the METERING
 TRACKING FREQUENCY  TRACKING FREQUENCY value for all computations, overriding the SOURCE FREQUENCY value.
6.3.4 SYNCHROCHECK
PATH: ACTUAL VALUES  METERING  SYNCHROCHECK  SYNCHROCHECK 1(4)
If a synchrocheck function setting is "Disabled", the corresponding actual values menu item is not displayed.
MESSAGE
SRC 1 POWER FACTOR
φa: 1.000
MESSAGE
SRC 1 POWER FACTOR
φb: 1.000
MESSAGE
SRC 1 POWER FACTOR
φc: 1.000
 FREQUENCY
 SRC 1
SRC 1 FREQUENCY:
0.00 Hz
 SYNCHROCHECK 1

SYNCHROCHECK 1 DELTA
VOLT: 0.000 V
MESSAGE
SYNCHROCHECK 1 DELTA
PHASE: 0.0°
MESSAGE
SYNCHROCHECK 1 DELTA
FREQ: 0.00 Hz

GE L30 Specifications

General

Brand	GE
Model	L30
Category	Relays
Language	English