Fluke 87 V - Manual (Page 38)

80 Series V
Users Manual
30
Determining Pulse Width
For a periodic waveform (its pattern repeats at equal time
intervals), you can determine the amount of time that the
signal is high or low as follows:
1. Measure the signal's frequency.
2. Press
G a second time to measure the signal's
duty cycle. Press E to select a measurement of
the signal's positive or negative pulse, refer to
Figure 9.
3. Use the following formula to determine the pulse
width:
Pulse Width = % Duty Cycle ÷ 100
(in seconds) Frequency
Bar Graph
The analog bar graph functions like the needle on an
analog meter, but without the overshoot. The bar graph
updates 40 times per second. Because the graph
responds 10 times faster than the digital display, it is
useful for making peak and null adjustments and
observing rapidly changing inputs. The graph is not
shown for capacitance, frequency counter functions,
temperature, or peak min max.
The number of lit segments indicates the measured value
and is relative to the full-scale value of the selected
range.
In the 60 V range, for example, the major divisions on the
scale represent 0, 15, 30, 45, and 60 V. An input of -30 V
lights the negative sign and the segments up to the
middle of the scale.
The bar graph also has a zoom function, as described
under "Zoom Mode".