Measurement Subsystem
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Series N6700 User’s Guide
Measurement Subsystem
The measurement subsystem consists of Measure, Fetch, and Sense
commands.
Measure
commands measure the output voltage or current. They
trigger the acquisition of new data before returning the reading.
Measurements are performed by digitizing the instantaneous output
voltage or current for a specified time interval, storing the results in
a buffer, and calculating the average value. Use Measure commands
when the measurement does not need to be synchronized with any
other event.
Fetch
commands return a reading computed from previously
acquired data. If you take a voltage measurement, you can fetch only
voltage data. If you take a current measurement, you can fetch only
current data. Use Fetch commands when it is important that the
measurement be synchronized with a triggered event.
Sense
commands controls the current measurement range, the
bandwidth detector of the power system, and the data acquisition
sequence.
NOTE
The FETCh:ARRay, MEASure:ARRay, and SENSe commands do not apply to all
models. Refer to Chapter 1, “Model Differences” for model-specific information.
FETCh:ARRay:CURRent[:DC]? (@<chanlist>
)
FETCh:ARRay:VOLTage[:DC]? (@<chanlist>)
MEASure:ARRay:CURRent[:DC]? (@<chanlist>)
MEASure:ARRay:VOLTage[:DC]? (@<chanlist>)
These queries return an array containing the digitized output current
in amperes or output voltage in volts. The data returned by the
FETCh command is the result of the last measurement command or
acquisition trigger. The data is valid until the next MEASure or
INITiate command occurs.
The output voltage or current is digitized whenever a measurement
command is sent or an acquisition trigger occurs. The sampling rate
is set by SENSe:SWEep:TINTerval. The position of the trigger relative
to the beginning of the data buffer is determined by
SENSe:SWEep:OFFSet. The number of points returned is set by
SENSe:SWEep:POINts.
