Campbell CR6 Series, Руководство оператора

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Section 8. Operation
402
where A-to-D conversion time equals 1/fN1 µs. If reps (repetitions) > 1 (multiple
measurements by a single instruction), no additional time is requir ed. If reps = 1
in consecutive voltage instructions, add 15 µs per instruction.
Measurement Accuracy
Read More For an in-depth treatment of accuracy estimates, see the
technical paper
Measurement Error Analysis
soon available at
www.campbellsci.com/app-notes.
Accuracy describes the difference between a measurement and the true value.
Many factors affect accuracy. This section discusses the affect
percent-or-reading, offset, and resolution have on the accuracy of the
measurement of an analog voltage sensor signal. Accuracy is defined as follows:
accuracy = percent -of-r offset
where percents-of-reading are tabulated in the table Analog Voltage Measurement
Accuracy
(p. 402),
and offsets are tabulated in the table Analog Voltage
Measurement Offsets
(p. 402).
Note Error discussed in this section and error-related specifications of
the CR6 do not include error introduced by the sensor or by the
transmission of the sensor signal to the CR6.
Analog Voltage Measurement Accuracy
1
0 to 40 °C –40 to 70 °C –55 to 85 °C
±(0.03% of r
offset)
±(0.03% of r
offset)
±(0.03% of r
offset)
1
Assumes the CR6 is within factory specifications
Analog Voltage Measurement Offsets
Input
Voltage Range
(mV)
Differential
Measurement
With Input or
Excitation
Reversal
(
µ
V)
Differential
Measurement
Without Input
or
Excitation
Reversal
( µ V)
Single-Ended
( µ V)
±
5000
±
40
±
70
±
140
±
1000
±
10
±
30
±60
±
200
±3 ±5 ±10