Measuring Pulse Width - Fluke 87 Series IV User Manual

To measure duty cycle, set up the meter to measure
frequency; then press
select the level the meter uses by pressing
trigger on the positive slope or
negative slope. A typical duty cycle display is shown in
Figure 3-16.
Figure 3-16. Duty Cycle Display
For 5 V logic signals, use the 5 V dc range. For 12 V
switching signals in automobiles, use the 50 V dc range.
For sine waves, use the lowest ac or dc range that does
not result in multiple triggering. A manually-selected lower
a second time. You can
to
to trigger on the
tc027f.eps
input range will measure better than the AUTO-selected
input range.
If a duty cycle reading is unstable, press
AVG annunciator comes on and the average reading
appears in the secondary display.

Measuring Pulse Width

The pulse width function allows you to measure the
amount of time a signal is high or low within a given
period. See Figure 3-17. The measured waveform must
be periodic: its pattern must repeat at equal time intervals.
Making Measurements
Measuring Pulse Width
until the
3-25
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