GE P643 User Manual

4 MEASUREMENTS
4.1 MEASURED QUANTITIES
The device measures directly and calculates a number of system quantities, which are updated every second. You
can view these v
alues in the relevant MEASUREMENT columns or with the Measurement Viewer in the settings
application software. Depending on the model, the device may measure and display some or more of the following
quantities:
● Measured and calculated analogue current and voltage values
● Power and energy quantities
● Peak, fixed and rolling demand values
● Frequency measurements
● Thermal measurements
4.1.1 MEASURED AND CALCULATED CURRENTS
The device measures phase-to-phase and phase-to-neutral current values. The values are produced by sampling
the analogue input quantities, conv
erting them to digital quantities to present the magnitude and phase values.
Sequence quantities are produced by processing the measured values. These are also displayed as magnitude and
phase angle values.
These measurements are contained in the MEASUREMENTS 1 column.
4.1.2 MEASURED AND CALCULATED VOLTAGES
The device measures phase-to-phase and phase-to-neutral voltage values. The values are produced by sampling
the analogue input quantities, conv
erting them to digital quantities to present the magnitude and phase values.
Sequence quantities are produced by processing the measured values. These are also displayed as magnitude and
phase angle values.
These measurements are contained in the MEASUREMENTS 1 column.
4.1.3 POWER AND ENERGY QUANTITIES
Using the measured voltages and currents the device calculates the apparent, real and reactive power quantities.
These ar
e produced on a phase by phase basis together with three-phase values based on the sum of the three
individual phase values. The signing of the real and reactive power measurements can be controlled using the
measurement mode setting. The four options are defined in the following table:
Measurement Mode Parameter Signing
0
(Default)
Export Power
Impor
t Power
Lagging Vars
Leading VArs
+
–
+
–
1
Export Power
Impor
t Power
Lagging Vars
Leading VArs
–
+
+
–
2
Export Power
Impor
t Power
Lagging Vars
Leading VArs
+
–
–
+
Chapter 13 - Monitoring and Control P64x
274 P64x-TM-EN-1.3

GE P643 Specifications

General

Brand	GE
Model	P643
Category	Relays
Language	English