I'm road testing the Keithley Bench Digital Multimeter DMM6500. In this post, a simple method to save measurements and list them in a table with a keypress.
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Saving Measurements to a Table
This is the default behaviour of the DMM. Measurements are stored in defbuffer1 when you switch on the meter.
I'm using this functionality to register a number of measurements, using the TRIGGER button to take a measurement.
I'm measuring a feedback circuit on my bench. I have a potentiometer that I set to a particular position, and I want to register the circuit's output voltage for that position.
I could use pen and paper to write down the measurements, but it's easier if I can store the data points on the meter, by pressing a button each time I want to store the value.
Even better if I can see the stored values on screen.
Manual Trigger Mode
Taking a measurement on command is done by setting the trigger to Manual Trigger Mode.
You do this by pressing the TRIGGER button for 3 seconds, and selecting the manual mode.
The display will stop updating. The next measurement is taken when you briefly push the TRIGGER button (try it!).
The meter will also store that measurement in defbuffer1.
Table View
You may want to clear the buffer before you display the table with measurements.
Do that via MENU -> Reading Buffers -> Clear -> Yes
Then switch to the table display.
MENU -> Reading Table
Place the probes on the circuit where you want to make your measurement. Each time you press TRIGGER, a fresh measurement is added to the table.
In the example below, I programmed a DAC from value 100 to 1000, in steps of 100.
Each time I changed the setting, I pushed the TRIGGER button to record the output of the DAC.
The purple line shows where you are on the graph. You can scroll through graph and table.
Tapping an entry shows reading details.
You can use this for any non-digitising meter function, like temp, capacity, current, ...
It theoretically works for digitising, but it will take many measures (1000 by default) at each TRIGGER press. Useful, but not what I want here.
Improvements
When you use this method, you don't see the current measurement until you press the TRIGGER button.
This could be a good candidate for an APP, where it always measures (Continuous Trigger Mode),
but stores the measurement in a custom buffer at the push of a button (could be the same TRIGGER button).
The custom display could be split in two. Active measurement on top, then the rest of the screen for the table display.
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