High Frequency Measurements With 10:1 Probe; Probe Attenuation; Probe Adjustment; Power And Harmonics Mode - Fluke ScopeMeter 123B User Manaul

High Frequency Measurements with 10:1 Probe

Fluke recommends the VP41 10:1 Probe to measure high
frequency signals in circuits with high impedance. The
loading of the circuit by a 10:1 Probe is much lower than
that of a 1:1 Shielded Test Lead.
Probe attenuation and probe adjustment must be
observed when using a 10:1 Probe.

Probe Attenuation

The Probe attenuates the signal 10X. The example below
is for a Probe connected to input A.
To adapt the Test Tool's voltage readout to this
attenuation:
1. Push  to open the Scope and Meter button bar.
2. Push 3 to open the INPUT SETTINGS menu.
YZ
3. Use to go to Select>.
4. Push  to open the PROBE SELECT menu.
YZ
5. Use to highlight 10:1 V.
6. Push  to make the change.
Observe that the 10X attenuation of the Probe is
compensated in the voltage readout.

Power and Harmonics Mode

Probe Adjustment

The VP41 Probe is always adapted correctly to its inputs.
High frequency adjustment is not necessary.
Other 10:1 Probes however must be adjusted for optimal
High Frequency performance. See 10:1 Scope Probes for
information about how to adjust these Probes.
Power and Harmonics Mode
The Power and Harmonics mode offers:
• Single phase power measurements with waveform and
harmonics display
• Voltage RMS, Current RMS, frequency, and phase
measurements
• Active, apparent, and reactive power measurements
• Power factor, cos ϕ, and total harmonic distortion
measurements
This section is a step-by-step introduction to power and
harmonics measurements. It does not cover all of the
capabilities of the Test Tool but gives basic examples to
show how to use the menus and perform basic
operations.
To use the power and harmonics functions, connect the
voltage leads and current probe as shown in Figure 7
setup 2.
Industrial ScopeMeter®
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