Each trace in the following image contains all twenty
PT()
mV/V values (left axis) for a given
record number and an average value showing the measurements as percent of final reading
(right axis). The reading has settled to 99.5% of the final value by the fourteenth measurement,
which is contained in variable
PT(14)
. This is suitable accuracy for the application, so a settling
time of 1400 µs is determined to be adequate.
9.10.7 Factors affecting accuracy
Accuracy describes the difference between a measurement and the true value. Many factors
affect accuracy. This topic discusses the effect percent-of-reading, offset, and resolution have on
the accuracy of an analog voltage measurement. Accuracy is defined as follows:
accuracy = percent-of-r offset
where percents-of-reading and offsets are displayed in the
Analog measurements specifications
NOTE:
Error discussed in this section and error-related specifications of the data logger do not
include error introduced by the sensor, or by the transmission of the sensor signal to the data
logger.
9. Tips and troubleshooting
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