Energy Counters; How The Energy Meter Works - Siemens simatic et200sp Manual

Energy counters

7.1

How the energy meter works

Introduction
The AI Energy Meter 480VAC ST provides 42 energy counters that detect both line-based
and phase-based energy values.
● Active energy (total, outflow, inflow)
● Reactive energy (total, outflow, inflow)
● Apparent energy (total)
How energy recording works
Based on the measured currents and voltages and the calculation cycle the Energy Meter
calculates the active, reactive and apparent energy. The active, reactive and apparent
energies are updated in each calculation cycle.
Retentivity
All the counter states of the module are stored retentively in the Energy Meter. After an
interruption (e.g. Power System Off → Power System On), the energy counting resumes with
the retentively stored values.
Configuring
You configure the following settings for the energy counters:
● Activation of the gate for the energy counter
The gate allows you to start and stop the counters via output data (DQ bit). If you
deactivate the gate, the count starts immediately when the Energy Meter is switched on.
● Modes of the energy counters
The energy counters count either infinitely or periodically. For periodic counting, the
adjustable full-scale values are 10
exceeded, the energy counter begins again at 0. At the same time the overflow counter is
increased by 1 (see Resetting energy counters and overflow counters (Page 48)).
The settings apply to the energy counter of all phases.
Analog input module AI Energy Meter 480VAC ST (6ES7134-6PA20-0BD0)
Manual, 12/2015, A5E36061895-AA
, 10 , 10 and 10 . When the full-scale value is
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