Measurements; Measured Quantities; Measured And Calculated Currents; Measured And Calculated Voltages - GE P24DM Technical Manual

P24xM
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 values 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

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Peak, fixed and rolling demand values
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Frequency measurements
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● 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, converting 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, converting 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 are 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
0
(Default)
1
2
P24xM-TM-EN-2.1
Parameter
Export Power
Import Power
Lagging Vars
Leading VArs
Export Power
Import Power
Lagging Vars
Leading VArs
Export Power
Import Power
Lagging Vars
Leading VArs
Chapter 13 - Monitoring and Control
Signing
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