USER'S MANUAL PD-185
This multimeter is AC coupled and will accurately measure the AC
RMS component of an input signal. The DC voltage function will
measure the DC component. To obtain the total true RMS value,
measure the RMS AC component on the AC function and the DC
component on the DC function. Then, calculate the True RMS value,
using the measured AC and DC components and the True RMS
expression given above.
AC converters of all types are limited by their frequency response
and input dynamic range. Measurements of complex waveforms will
not be affected by converter bandwidth limitations, provide that all
significant AC components contained within the waveforms are
within the bandwidth of the converter.
Crest factor is a measure of the input dynamic range of an AC
converter. It expresses the ability of the converter to accept a signal
that has large peak values compared to its RMS value without
saturating the converter circuitry and degading the specified
accuracy. Crest factor is defined as the ratio of the peak voltage to
the total AC RMS voltage.
4.4 How to make measurements
Before making any measurements always examine the instrument
and
accessories
used
with
the
instrument
for
damage,
contamination (excessive dirt, grease, ect.) and defects. Examine
the test leads for cracked or frayed insulation and make sure the
lead plugs fit snugly into the instrument jacks. If any abnormal
conditions exist do not attempt to make any measurements.
11/2015
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