Fluke 8845A, User Manual

Page: 85 / 103

Making Measurements
Making a Triggered Measurement
4
4-17
Four soft keys allow changing the test voltage and current applied to the diode through
the test leads. The compliance voltage is set to either 5 volts or 10 volts. The compliance
current is set to either 1 mA or 0.1 mA. Press the appropriate soft key to select the desired
voltage and current setting.
Making a Triggered Measurement
Triggering the Meter’s measurement cycle is set through the trigger menu and performed
via a connection on the Meter’s rear panel or the front panel trigger key. The trigger
menu also allows setting a trigger delay and setting the number of samples or
measurement cycles taken for each trigger received. All trigger function parameters are
accessed through the measurement setup key.
Press
L
to see the measurement setup menu.
A measurement trigger can also be initiated through the IEEE 488 port with a remote
command. This method of triggering is covered in the 8845A/8846A Programmers
Manual .
Setting the Trigger Mode
The Meter’s measurement cycle can be initiated either by the internal measurement
circuit or by external stimulus.
To select the trigger mode:
1.
With the measurement setup menu displayed, press the soft key labeled
TRIGGER
.
If
EXT TRIG
is highlighted, the Meter’s measurement cycle is triggered externally
either through the external trigger jack on the rear panel, or the trigger key on the
front panel. If
EXT TRIG
is not highlighted, then the Meter’s measurement cycle is
triggered automatically by its internal circuitry.
2. Press the soft key labeled
EXT TRIG
to toggle between internal and external
triggering.
Setting a Trigger Delay
When in external trigger mode, the Meter is capable of delaying the start of the
measurement cycle after the trigger stimulus is sensed by up to 3600 seconds.
To set a trigger delay:
1.
With the measurement setup menu displayed, press the soft key labeled
TRIGGER
.
2. Press the soft key labeled
TRIG DELAY
.
3. Use the soft keys to set the trigger delay.
Select the digit in the value by pressing either
<--
or
-->
.
With the desired digit selected, press the soft key labeled
--
to decrement the digit
or
++
to increment the character.
4. Press
ENTER
.
Setting Number of Samples per Trigger
When in external trigger mode, the Meter will take between 1 and 50,000 measurements
for each trigger received.
To set the number of samples, or measurements the Meter will take for each external
trigger received: