Schneider Electric PM5100 Manual De Usuario

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PowerLogic™  PM5100 series user guide 
Chapter 8—Measurements and calculations
© 2014 Schneider Electric All Rights Reserved
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Chapter 8—Measurements and calculations
This section describes how the meter processes measured and calculated data.
Real-time readings
The power and energy meter measures currents and voltages, and reports in real time 
the RMS (Root Mean Squared) values for all three phases and neutral. The voltage and 
current inputs are continuously monitored at a sampling rate of 64 points per cycle. This 
amount of resolution helps enable the meter to provide reliable measurements and 
calculated electrical values for various commercial, buildings and industrial 
applications.
Related topics
To learn how to navigate to the data screens using the front panel, see “Viewing 
Meter Data” on page 43.
Energy
The power and energy meter calculates and stores accumulated energy values for real, 
reactive, and apparent energy. 
You can view accumulated energy from the display. The energy value units 
automatically change, based on the quantity of energy accumulated (e.g., from kWh to 
MWh
, from MWh to GWh, then from GWh to TWh, from TWh to PWh).
Related topics
To view energy readings from the front panel display, see “Meter data display 
screens” on page 43.
Min/max values
The meter’s real-time readings are updated once every 50 cycles for 50 Hz systems, or 
once every 60 cycles for 60 Hz systems. When the readings reach their lowest or 
highest value, the meter updates and saves these min/max (minimum and maximum) 
quantities in non-volatile memory.
Power factor
Power factor (PF) is the ratio of active power (P) to apparent power (S), and is a 
number between zero (0) and one (1). In a purely resistive circuit, PF is equal to 1 (unity 
PF). Inductive or capacitive loads increase the reactive power (Q) component in the 
circuit which causes the PF to become less than 1.
Power factor can have a positive or negative sign, depending on the type of load or 
direction of power flow. See “Power factor sign convention” on page 62.