PeakTech 4090 Bedienungsanleitung Seite 37

6.8. Capacitance measurements
Caution!
Turn off power and discharge the capacitor before attempting a capacitance measurement. Use the
DCV function to confirm that the capacitor is discharged.
1. Set Function-Switch to the -| |- - position.
2. Insert red test lead to mV//Hz-input and black test lead to the COM-input.
3. Connect the test leads to the capacitor. Observe polarity when measuring polarized capacitors.
4. Read the capacitance directly from the display. A shorted capacitor will indicate an over range.
An open capacitor will indicate near zero on all ranges.
Note:
1. To avoid large error, don't measure a capacitor if this capacitor is connected in parallel with a
circuit.
2. When measuring capacitance between 220µF and 20mF, to ensure accuracy, the meter takes a
relative long time to discharge the capacitor so that it is relatively slow in refreshing the
measured value.
6.9. Measuring Linear Frequency
Warning !!
Do not try to measure the frequency of a signal that exceeds 250 volts AC
instrument and expose yourself to a severe shock hazard.
Follow these steps to measure the frequency of a signal.
1. Set Function-Switch to the Hz/Duty-position.
2. Press "Hz/Duty"-button to the select frequency-measurement.
3. Plug the black test lead into the COM-terminal and the red test lead into the mV/-terminal.
4. Connect the test lead to the frequency source.
Warning:
When the test leads are connected to an AC outlet, do not select other ranges. It might damage the
internal components or cause bodily injury.
1. When you make voltage or current measurement, you can press the Hz/Duty button to change to
frequency measurement (" Hz" appears on the display ) and measure the frequency if the
measured signal is an ac signal or contains AC component.
Note:
The amplitude of the AC signal must meet the meter's requirement. For different ranges, the required
signal amplitudes are different.
2. Press the Hz/Duty button again to select duty cycle measurement (" % " appears on the display )
and measure the duty cycle.
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. It may damage your
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