AMETEK BPS Series Programming Manual - Manual (Page 156)

AMETEK Programmable Power BPS / MX / RS Series SCPI Programming Manual
156 Manual P/N 7003-961 Rev AA
6.6 Acquiring Measurement Data
The source has the capability to return a number of current, voltage, and power
measurements. When the AC source is turned on, it is continuously sampling the
instantaneous output voltage and current for several output cycles and writing the results
into a buffer. The buffer holds 4096 voltage and current data points.
The AC source uses the data from the voltage and current buffer to calculate the requested
measurement information. Data in the voltage and current buffers is always re-acquired for
subsequent measurement requests. There are two ways to make measurements:
• Use the MEASure commands to immediately start acquiring new voltage and current
data, and return measurement calculations from this data as soon as the buffer is full.
This is the easiest way to make measurements, since it requires no explicit trigger
programming.
• Use an acquisition trigger to acquire the voltage and current data from the buffer. Then
use the FETCh commands to return calculations from the data that was retrieved by the
acquisition trigger. This method gives you the flexibility to synchronize the data
acquisition with an external signal. FETCh commands do not trigger the acquisition of
new measurement data, but they can be used to return many different calculations from
the same set of data that was captured as a result of same acquisition trigger.
The query response for measurements is not immediate. The source will accept commands
from the interface while the measurement in progress. To prevent the source from accepting
additional commands during measurement the *WAI must be used with the measurement
query command.
MEAS:FREQ?;*WAI
Making triggered measurements with the acquisition trigger system is discussed under
"Triggering Measurements".
Note For each MEASure form of the query, there is a corresponding query
that begins with the header FETCh. FETCh queries perform the same
calculation as their MEASure counterparts, but do not cause new data
to be acquired. Data acquired by an explicit trigger or a previously
programmed MEASure command are used.