ALL-TEST PRO ATPOL II, Руководство пользователя

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True power equals apparent power when there is no phase lag in the load and no harmonics are
present, otherwise it is less than the apparent power. This is why an ammeter cannot be used to
accurately measure true power in most industrial circuits.
Reactive power is the square root of the difference between the squares of the apparent power and the
true power:
2 2
var
( )
app true
P VAR P P
  
.
When the fundamental voltages and currents are in phase and no harmonic currents are present,
reactive power is zero.
Peak demand of the demand period is an important measurement that is covered in the
Demand
Period Measurements section.
Power Measurements in ATPOL II
ATPOL II performs all commonly desired power
measurements.
Total true power (watts or KW), total reactive power
(VAR or KVAR), and total apparent power (VA or KVA)
measurements are available by simply pressing
[Power] repeatedly. The sequence of the display is
KW > KVAR > KVA. If energy consumption is being
monitored, the maximum, minimum, and average
power is displayed by repeatedly pressing [More...]
after displaying the appropriate power type. In this
way, by combining the [Power] and [More...] keys,
there are 12 power measurements available.
For instance, if the maximum reactive power is
desired, press: [Power] (to display watts), [Power] (to
display VAR), and then [More...] (to display maximum reactive power). After showing the total VAR, a
summary of each phase’s true power and VA power are shown.
Power Measurements in PSM
The consumption data log can record maximum, minimum, and average true power and apparent
power for each phase for each logging period. In addition is can record the maximum, minimum, and
average true or apparent total power. When graphed, the VAR can be displayed. The summary values
at the top of the screen are the maximum, minimum, and average of all the values shown on the
screen.
When viewing consumption waveforms, the average true power of the cycles of the waveforms are
shown at the top right (if both voltage and current were recorded. If all phases are displayed, only the
total true power is displayed at the top right. If a harmonic analysis of a phase is displayed, the true
power of that phase is also displayed.
If trending data is being recorded and in phase-phase voltage measurement mode, the average true
power and average apparent power of each phase will be displayed and recorded. If in phase-phase