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8 - Manual setup
Timing options
68
SMU4000 Series Instruction Manual
Measurement
Period
CNFG >
[Source Measure Action] Manual Setup
>
[Timing] Measure
The Measurement period also known as aperture or integration time defines the amount of
time that each measurement is measured and averaged for. The entry can be made in terms of
seconds or number of power line cycles (PLC).
Accuracy of measurements can be affected and reduced by power line induced AC noise, this
effect can be counteracted by increasing the measurement period, however only an integer
number of PLC values provide mains power line rejection.
One PLC for 50Hz is 20ms and one PLC for 60Hz is 16.67ms. Mains input frequency is
automatically monitored and applied by the instrument. Matching and tracking the PLC
measurement period to the exact mains frequency period will remove as much power line
generated interference and noise as possible.
The measurement period is a trade-off between measurement accuracy and measurement
speed.