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HT9023
EN - 5
2. GENERAL DESCRIPTION
The instrument carries out the following measurements:
DC voltage up to 1500V
AC, AC+DC TRMS voltage up to 1000V
“Voltsense” sensor for detection AC voltage without contact
DC, AC, AC+DC TRMS current up to 1000A
Resistance and continuity test
Phase sequence and conformity test with 1 wire
Measure/Recording AC Powers on single-phase and/or balanced three phase systems
Measure/Recording power factor on single-phase and/or balanced three phase
systems
Measure/Recording AC energies on single-phase and/or balanced three-phase
systems
Measure/Recording DC power and energy
Measure/Recording AC voltage harmonics up to 25° order and THD%
Measure/Recording AC current harmonics up to 25° order and THD%
Frequency voltage and current
Electric motor starting currents (Dynamic Inrush)
WiFi interface for PC and mobile device connection
Each of these functions can be selected using the selector switch. Keys
F1
,
F2
,
F3
,
F4/OK
and
H/ESC/
are also provided. For their use, please refer to § 4.2.
2.1. MEASURING
AVERAGE
VALUES AND TRMS VALUES
Measuring instruments of alternating quantities are divided into two big families:
AVERAGE-VALUE meters: instruments measuring the value of the single wave signals
TRMS (True Root Mean Square) VALUE meters: instruments measuring the TRMS
value of the quantity being tested
In the presence of a perfectly sinusoidal wave, both families of instruments provide
identical results. In the presence of distorted waves, on the other hand, the readings shall
differ. Average-value meters provide the RMS value of the sole fundamental wave, TRSM
meters, instead, provide the RMS value of the whole wave, including harmonics (within the
instrument’s bandwidth)
2.2.
DEFINITION OF TRUE ROOT MEAN SQUARE VALUE AND CREST FACTOR
The root mean square value of current is defined as follows: "
In a time equal to a period,
an alternating current with a root mean square value of the intensity of 1A, circulating on a
resistor, dissipates the same energy as that which would have been dissipated by a direct
current with the intensity of 1 A during the same time
". This definition results in the
numeric expression:
G=
T
t
t
dt
t
g
T
0
0
)
(
1
2
The
root mean square value
is indicated with the acronym RMS. The
Crest Factor is defined as the relationship between the Peak Value of a signal and its RMS
value: CF (G)=
RMS
p
G
G
This value changes with the signal waveform, for a purely sinusoidal
wave it is
2
=1.41. In case of distortion, the Crest Factor takes higher values as wave
distortion increases.