Hioki PW3198 User Manual

Appendix 7 Terminology
A
26
Out of crest factor
However, when a measurement that exceeds the peak is input, it appears outside the crest
factor and you are informed of data that contains measurement errors.
High-order
harmonic component
The noise component at and above several kHz. For the PW3198, the term refers to RMS val-
ues for the noise component at 2 kHz and above. By measuring the high-order harmonic com-
ponent, it is possible to monitor harmonic noise at the 50th and higher order emitted by
switching power supplies, inverters, LED lighting, and other devices. Recently, increases in the
switching frequencies used by switching power supplies and inverters have resulted in the
problematic introduction of noise in excess of 10 kHz into power supply lines.
Nominal supply
voltage (Uc)
Typically, the system's rated voltage Un. When a voltage that differs from the rated voltage
is applied to the contact in accordance with an agreement between the electricity provider
and the customer, that voltage is used as the nominal supply voltage Uc. The nominal sup-
ply voltage is defined by IEC61000-4-30.
Nominal voltage (Uref)
The same voltage as the nominal supply voltage (Uc) defined by IEC61000-4-30 or the
rated voltage (Un). Nominal voltage (Uref) = nominal input voltage (Udin) × VT ratio
Nominal input voltage
(Udin)
The value calculated from the nominal supply voltage using the transformer ratio. The
nominal input voltage is defined by IEC61000-4-30.
Harmonics
A phenomenon caused by distortions in the voltage and current waveforms that affect many
devices with power supplies using semiconductor control devices. In the analysis of non-sine
waves, the term refers to one RMS value among the components with harmonic frequencies.
Harmonics
phase angle and Phase
difference
The harmonic voltage phase angle and harmonic current phase angle are expressed in
terms of the synchronized source's fundamental component phase.
The difference between each order's harmonic component phase and the fundamental
component phase is expressed as an angle (°), and its sign indicates either a lagging
phase (negative) or leading phase (positive). The sign is the reverse of the power factor
sign. The harmonic voltage-current phase angle expresses the difference between each
order's harmonic voltage component phase angle and harmonic current component phase
angle for each channel as an angle (°).
When using the sum display, the sum of each order's harmonic power factor (calculated
from the sums of harmonic power and harmonic reactive power) is converted to an angle
(°). When the harmonic voltage-current phase angle is between -90° and +90°, that order's
harmonics are flowing toward the load (influx). When the harmonic voltage-current phase
angle is between +90° and +180°
or between -90° and -180°, that order's harmonics are
flowing from the load (outflow).
200
50 2
50
0
-50
-200
[A]
16-bit resolution
Crest factors of the PW3198
(The crest factor of the current input area is 4.)
0°
90°
-90°
±180°
Harmonic phase angle
Voltage and current
phase difference
Outflow Inflow
LEAD
LAG
Voltage and current
phase angles

Hioki PW3198 Specifications

General

Brand	Hioki
Model	PW3198
Category	Measuring Instruments
Language	English