Using The Histogram Function - Fluke 8845A User Manual

8845A/8846A
Users Manual
As shown in Figure 3-1, the display will start plotting the readings across the plot area,
and the maximum, minimum, and elapsed time are displayed.
To stop the TrendPlot session, press B or the STOP soft key.
To start the TrendPlot session over, press the STOP soft key followed by the
RESTART soft key.

Using the Histogram Function

The Histogram function provides a graphical representation of the standard deviation of a
series of measurements. The right two-thirds of the Meter's display is used as a bar graph
chart. The vertical axis is a relative measure of the number of readings while 10 vertical
bars represent the standard deviation across the horizontal axis. The two center bars
indicates the number of readings that fall on either side of the average reading within the
st
1 standard deviation. The two bars on either side of the center two bars represent the
number of readings that fall within the 2
rd
3 standard deviation and so on to the 5
The histogram function is helpful in looking at the standard distribution of the UUT.
While observing the bar graph display (see Figure 3-2), adjust the UUT variable control
to peak the center two bars of the histogram.
In addition to the bar graph, the left third of the display also displays the number of
samples, the average, and standard deviation values.
To start a histogram session:
1. Set up the Meter for the desired measurement by selecting the function, and
2. With the Meter taking measurements, press J.
3. Press HISTOGRAM to start the session.
3-14
STOP
F1
Figure 3-1. TrendPlot Display
F1
Figure 3-2. Histogram Display
connecting the signal to the Meter's input.
F2 F3 F4
nd
standard deviation. The next two represent the
th
standard deviation.
F2 F3 F4
F5
F5
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