Benning MM 7-2, Operating Manual

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5.3 Voltage, frequency or duty cycle measurement
Operation
5235 / 05/2022 en BENNING MM 7-2 34
5.3 Voltage, frequency or duty cycle measurement
Requirements
• Please observe the requirements for measuring [ } page 32].
• Approved safety measuring lines
• Voltage ranges [
}
page 26] and frequency ranges [
}
page 30]
Figure 9: Voltage, frequency or duty cycle measurement
Procedure
1. Set the rotary switch of the device to switch position “V‑AC”, “V”, “mV” or “AutoV LoZ”.
2. Connect the safety measuring lines to the device [
}
page 33].
3. Set the desired measuring function.
– “V‑AC”: If necessary, you can enable the “HFR (AC)” function (low-pass filter) by
pressing the blue “Function” key. As an alternative to voltage measurement, you can
switch to frequency measurement by pressing the “Hz” key.
– “V”: Press the blue “Function” key to set the desired coupling mode of the voltage
measurement (DC or AC+DC). As an alternative to voltage measurement, you can
switch to frequency measurement by pressing the “Hz” key.
– “mV”: Press the blue “Function” key to set the desired coupling mode of the voltage
measurement (DC, AC or AC+DC) or, for logic signals, to set frequency or duty cycle
measurement.
– “AutoV LoZ”: The corresponding measuring function (AC or DC voltage) and the
optimum measuring range are set automatically. The input resistance is briefly reduced
to approx. 2.1 kΩ in order to suppress unwanted inductive and capacitive voltages
(reactive voltages).
4. Bring the safety measuring lines into contact with the measuring points and read the
measured value on the digital display.