Fluke 8845A, User Manual

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8845A/8846A
Users Manual
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Figure 3-2. Histogram Display
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
connecting the signal to the Meter’s input.
2. With the Meter taking measurements, press
J
.
3. Press
HISTOGRAM
to start the session.
The display will start adjusting the bar graph as the number of readings accumulates. The
mean and standard deviation values also change in accordance with the collected
readings.
To start the histogram session over, press the
STOP
soft key followed by the
RESTART
soft key.
To stop the histogram session, press
B
or the
STOP
soft key.
Controlling Trigger Functions
The Meter’s trigger functions allows you to select a measurement trigger source, set the
number of measurements (samples) per trigger, and set the delay time between receiving
the trigger and the start of a measurement. In addition, the trigger function provides a
“measurement complete” signal on the trigger port on the rear panel. See item 5 in
Table 3-3. Triggering the Meter remotely through one of its communication interfaces is
covered in the Programmers Manual. The following sections discuss triggering the Meter
automatically (internal trigger), or externally using the trigger key on the front panel and
the trigger connector on the rear-panel.
Setup and control of the trigger function is accessible through the Meter’s Measurement
Setup key
L
.
Choosing a Trigger Source
There are four possible sources for triggering a Meter measurement: automatic, front
panel trigger key
W
, external, and remote. With the exception of remote triggering,
trigger source selection is through the trigger menu, found under the measurement setup
menu.
To select a trigger source:
1.
Press
L
to see the measurement setup menu.
2. Press the
TRIGGER
soft key to reveal the trigger control selections.