Fluke ScopeMeter 123B, Руководство пользователя

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123B/124B/125B
Users Manual
Harmonics Measurements
Harmonics are periodic distortions of voltage, current, or
power sine waves. A waveform can be considered a
combination of various sinewaves with different
frequencies and magnitudes. The contribution of each
component 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, TVs, and adjustable speed motor
drives. Harmonics can cause transformers, conductors,
and motors to overheat.
In the Harmonics function, the Test Tool measures
harmonics to the 51
st
. Related data such as DC
components, THD (Total Harmonic Distortion), and
K factor are measured.
You can display the harmonics of:
• Voltage measurements on Input A
•
Current measurements on Input B
• Power measurements calculated from Voltage
measurements on Input A and Current
measurements on Input B.
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 (

/

/

) and

are locked.
Input A is forced to measure voltage. Input B is forced to
measure current.
To make harmonics measurements:
1. Push
2
to select the harmonics display.
2. Push
1
to toggle between the voltage, current or
power readings.
3. Push
4
to turn on the cursor.
When the harmonics display with voltage measurements
is selected, the screen shows as in Table 6. For
harmonics display when current measurements are
selected, see Table 7. For harmonics display when watts
measurements are selected, see Table 8.
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