LEM Analyst 2050, Руководство пользователя, Страница: 22 / 140

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Key features include:
•
Easy to use Windows format
•
Data presentation in display mimic, table and
chart modes
•
Waveform, harmonics and data download
•
Harmonics analysis of waveforms
•
Logging of up to 5 parameters, waveforms and
harmonics
•
Simple exporting of data and trends into other
applications
4. TECHNICAL DEFINITIONS
4.1 Measured Parameters
THD Total Harmonic Distortion, the level of
harmonic distortion as a percentage of
the waveform value at the fundamental
frequency.
DF Distortion Factor, the level of harmonic
distortion as a percentage of the total
RMS value of the waveform.
F
0
Fundamental frequency in Hz
CF Crest Factor, the ratio of the peak value
to the RMS value.
Rpl Ripple, the AC RMS value as a
percentage of the DC component.
Pk Maximum positive or negative value
(>2ms) of a repetitive waveform. Not
suitable for single events.
4.2 Watts/ VA/ VAR/ PF Sign Conventions
For ease of use the following sign conventions have been
used.
Single phase/ Three phase measurements.
•
Watts . The sign indicates the direction of power flow.
No sign: indicates a power flowing in the conductor on
which the instrument is clamped, in the direction of
the arrow on the instrument case.
"_" sign: indicates a power flowing in the conductor
on which the instrument is clamped, in the direction
opposite to the arrow on the instrument case.
•
PF . The sign indicates the leading or lagging status of
the current, with reference to the voltage.
No sign: The current leads the voltage (capacitive
load).
"_" sign: The current lags the voltage (inductive load).
•
VAR . No sign is displayed.