Section 8. Operation
(V+ + V–)/2 or the voltage remaining on the inputs when V
dm
= 0. The total
voltage on the V+ and V– inputs is given as V+ = V
cm
+ V
dm
/2, and V
L
= V
cm
–
V
dm
/2, respectively.
Measurement Accuracy
Read More
For an in-depth treatment of accuracy estimates, see the technical
paper
Measurement Error Analysis
available at
www.campbellsci.com/app-notes
(http://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. 313),
and offsets are tabulated in the table
Analog-Voltage
Measurement Offsets
(p. 313).
Note
Error discussed in this section and error-related specifications of the
CR1000 do not include error introduced by the sensor or by the transmission of
the sensor signal to the CR1000.
Table 56.
Analog-Voltage Measurement Accuracy
1
0 to 40 °C
–25 to 50 °C
–55 to 85 °C
2
±(0.06% of r offset)
±(0.12% of r offset)
±(0.18% of r offset)
1
Assumes the CR1000 is within factory specifications
2
Available only with purchased extended temperature option (-XT)
Table 57.
Analog-Voltage Measurement Offsets
Differential Measurement
With Input Reversal
Differential Measurement
Without Input Reversal
Single-Ended
1.5 • Basic Reso 1.0
µ
V
3 • Basic Reso 2.0
µ
V
3 • Basic Reso 3.0
µ
V
Note
— the value for Basic Resolution is found in the table
Analog-Voltage Measurement
Resolution
(p. 313).
Table 58.
Analog-Voltage Measurement Resolution
Input
Voltage Range
(mV)
Differential
Measurement
With Input Reversal
(
µ
V)
Basic Resolution
(
µ
V)
±
5000
667
1333
±
2500
333
667
±
250
33.3
66.7
25
3.33
6.7
313
Summary of Contents for CR1000
Page 2: ......
Page 4: ......
Page 6: ......
Page 32: ......
Page 36: ......
Page 38: ......
Page 40: ......
Page 60: ...Section 4 System Quickstart Figure 16 PC200W View Line Graph 60 ...
Page 96: ......
Page 98: ...98 ...
Page 302: ......
Page 453: ...Section 8 Operation Figure 115 Using the Keyboard Display 453 ...
Page 456: ...Section 8 Operation Figure 118 Real Time Custom 456 ...
Page 457: ...Section 8 Operation 8 8 1 3 Final Memory Tables Figure 119 Final Memory Tables 457 ...
Page 458: ...Section 8 Operation 8 8 2 Run Stop Program Figure 120 Run Stop Program 458 ...
Page 460: ...Section 8 Operation Figure 122 File Edit 460 ...
Page 461: ...Section 8 Operation 8 8 4 PCCard Memory Card Display Figure 123 PCCard CF Card Display 461 ...
Page 478: ......
Page 506: ......
Page 536: ......
Page 636: ......
Page 642: ......
Page 644: ......
Page 676: ......
Page 677: ......