Agilent Technologies 4156b, User Manual, Page: 55 / 414

Agilent 4155B/4156B User’s Guide Vol.2, Edition 5 2-15
Measurement Mode
Sampling Measurement Mode
Sampling Interval and Measurement Time
When the sampling interval enough longer than the actual measurement time,
measurement unit repeats measurement every specified sampling interval. However,
if the sampling interval is less than the measurement time, measurement unit cannot
repeat measurements every specified interval. For example, if the measurement time
is one and a half the specified sampling interval, the interval of measurement is two
times the sampling interval. See Figure 2-6 which explains the operation of the
sampling measurement.
Measurement time depends on the measurement condition: integration time,
measurement range, and so on. So if you want to execute sampling measurement
with the specified sampling interval, you need to know the actual measurement time
upon your measurement setup, and set the sampling interval value enough longer
than the actual measurement time. You can see typical measurement time by
repeating the sampling measurements with several sampling interval settings. See
“Sampling Measurement Data” on page 2-18.
Measurement time is given by the following fomula:
Tmeas = Toh
where,
Tmeas : Measurement time.
Tinteg : Integration time.
Toh : Overhead time caused by the following elements:
• range changing time during measurement (when measurement
ranging mode is set to auto or limited auto)
• range changing time at measurement start (when using measurement
range less than the compliance value)
• time required for the compensation: getting compensation data and
compensating measurement data (when the automatic compensation
is set and executed)