User`s guide

285
Chapter 7 Tutorial
Measurement Fundamentals
4
7
Calculate the approximate measurement error for a pulse train input
with a crest factor of 3 and a fundamental frequency of 20 kHz. The
internal DMM is set to the 1 V range. For this example, use the 90-day
accuracy specifications of ± (0.05% of reading + 0.04% of range), as shown
in chapter 8.
Error
sine
= ±(0.05% + 0.04%) = ±0.09%
Error
crest factor
= 0.15%
Error
bandwidth
= * 100 = 1.4%
Total Error = 0.09% + 0.15% + 1.4% = 1.6%
Example: Calculating Measurement Error
3–
2
20000
4 3.14159 1000000
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