Keysight Technologies AC6801B, Руководство по эксплуатации и обслуживанию

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FETCh and MEASure Subsystems
The FETCh and MEASure subsystems return measured data. The FETCh and MEASure queries do not
take any parameters, and they have the identical syntax (such as FETCh:VOLTage:AC? and
MEASure:VOLTage:AC?).
Measurements may be acquired continuously or non-continuously, as specified by
INITiate:CONTinuous:ACQuire . The *RST and *RCL commands disable continuous operation.
Non-continuous measurement mode
MEASure Subsystem
A MEASure query or an IMMediate or BUS trigger generates a new measurement that is stored in a
buffer and then returned to the user.
Before the instrument can accept an IMMediate or BUS trigger, you must first send INITiate:ACQuire.
Otherwise, the instrument will generate SCPI error -211,"Trigger ignored" . The buffer retains the
measured data until cleared by another MEASure query, an accepted IMMediate or BUS trigger, a
*RST or INITiate:ACQuire command, or a power cycle.
FETCh Subsystem
A FETCh query immediately returns the previously acquired measurement from this buffer. If no
measurement is in the buffer, the instrument generates SCPI error -230,"Data corrupt or stale".
General Measurement Operation
Data acquisition occurs at 333 ms intervals, which includes a digitization aperture of 100 to 125 ms. If
there are no MEASure queries or triggers, the data is discarded.
When a MEASure query or IMMediate or BUS trigger is received, the instrument waits for the current
digitization to finish, discards the data, and waits for the next measurement interval to finish. The
instrument then stores the next measurement into the buffer to ensure that the entire measurement
was sampled after the MEASure query or IMMediate or BUS trigger. Therefore, a measurement could
require from 333 to 666 ms to complete.
The acquired measurement includes both the instantaneous voltage and current. The FETCh query
may return any calculated measurement item derived from this data, including FETC:CURR:DC?,
FETC:VOLT:AC?, and FETC:POW:ACDC?.
For averaged measurements of 2, 4, 8, or 16 intervals, the instrument stores and averages multiple
measurements. Therefore, a measurement could take up to 17 x 333 ms to complete.
Continuous measurement mode
Internal data acquisition occurs at 333 ms update intervals, including the aperture as described
above, and each completed measurement overwrites the previous data in the buffer. Averaged
Keysight AC6800B Series Operating and Service Guide 125
3 SCPI Programming Reference