Harmonics; Introduction; Measuring Harmonics - Fluke 125 User Manual

Introduction

In the Harmonics function the test tool measures
rd
harmonics to the 33 (for 400 Hz up to 25
such as DC components., THD (Total Harmonic
Distortion), and K-factor are measured.
Harmonics are periodic distortions of voltage, current, or
power sinewaves. A waveform can be considered as a
combination of various sinewaves with different
frequencies and magnitudes. The contribution of each of
these components to the full signal is measured.
Harmonics power distribution systems are often caused by
non-linear loads such as switched mode DC power
supplies in computers, TV's and adjustable speed motor
drives. Harmonics can cause transformers, conductors,
and motors to overheat.

Measuring Harmonics

You can display harmonics of:
th
). Related data
• Voltage measurements on Input A
• Current measurements on Input B
• Power measurements calculated from Voltage
In the Harmonics mode the test tool always uses the
AUTO mode. The vertical sensitivity range and the time
base range are automatically adjusted to the most suitable
range for the applied input signal. The ranging keys
(mV V and s TIME ns) and the AUTO key are locked.
Input A is forced to measure voltage, input B is forced to
measure current.
measurements on Input A and Current measurements
on Input B.
Chapter 3

Harmonics

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