Frequency (Hz) Measurements
Frequency is the number of cycles a signal completes each second. The meter
measures the frequency of a voltage or current signal by counting the number of
times the signal crosses a threshold level each second.
To measure the frequency of a voltage or current signal, press the Hz/Duty button
momentarily while measuring volts or currents.
The available frequency ranges are 5 Hz, 50 Hz, 500 Hz, 5 kHz, 50 kHz, 500 kHz,
5 MHz and 10 MHz.
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Caution
Using resistance and continuity function in a live circuit will
produce false results and may damage the instrument.
In many cas es the s uspic ious c omponents mus t be
disconnected from the circuit under test to obtain accurate
results.
Tips for measuring frequency
•
In frequency, the meter is always autoranging.
•
When disconnecting the input terminals, the overload sign may be displayed or
the display may unsteadily fluctuate. This is typical.
Duty Cycle Measurements
Duty Cycle (or Duty Factor) is the percentage of time a signal is above or below a
trigger level during one cycle.
The duty cycle mode is optimized for measuring the ON or OFF time of logic and
switching signals. Systems such as electronic fuel injection systems and switching
power supplies are controlled by pulses of varying width, which can be checked by
measuring duty cycle.
Press the Hz/Duty button to toggle between the Hz mode and the Duty Cycle mode
when the rotary selector knob is set to Hz (Duty).
Capacitance Measurements
Capacitance is the ability of a component to store an electrical charge.
The unit of capacitance is the farad (F). Most capacitors are in the nanofarad (nF)
to microfarad (µF) range.
The available capacitance ranges are 40nF, 400 nF, 4 µF, 40 µF, and 100 µF.
Caution
To avoid damaging the meter or the equipment under test,
remove all power from the circuit and discharge all high-
voltage capacitors before measuring capacitance.
Large value capacitors should be discharged through an
appropriate resistance load. Use the dc voltage function to
confirm that the capacitor is discharged.
