Section 8. Operation
309
Figure 98: Circuit to limit control port input to 5 Vdc
8.1.9 Field Calibration
Read More!
Field Calibration of Linear Sensors (FieldCal)
(p. 151)
has complete
information.
Calibration increases accuracy of a measurement device by adjusting its output, or
the measurement of its output, to match independently verified quantities.
Adjusting a sensor output directly is preferred, but not always possible or
practical. By adding
FieldCal()
or
FieldCalStrain()
instructions to the CR800
program, a user can easily adjust the measured output of a linear sensors by
modifying multipliers and offsets.
8.1.10 Cabling Effects
Sensor cabling can have significant effects on sensor response and accuracy. This
is usually only a concern with sensors acquired from manufacturers other than
Campbell Scientific. Campbell Scientific sensors are engineered for optimal
performance with factory-installed cables.
8.1.10.1 Analog Sensor Cables
Cable length in analog sensors is most likely to affect the signal settling time. For
more information, see
Signal Settling Time
(p. 282).
8.1.10.2 Pulse Sensors
Because of the long interval between switch closures in tipping bucket rain gages,
appreciable capacitance can build up between wires in long cables. A built-up
charge can cause arcing when the switch closes, shortening switch life. As shown
in figure
Current Limiting Resistor in a Rain Gage Circuit
(p. 309),
a 100-ohm
resistor is connected in series at the switch to prevent arcing. This resistor is
installed on all rain gages currently sold by Campbell Scientific.
Figure 99: Current limiting resistor in a rain gage circuit
Содержание CR850
Страница 2: ......
Страница 4: ......
Страница 6: ......
Страница 26: ...Table of Contents 26...
Страница 30: ...Section 2 Cautionary Statements 30...
Страница 32: ...Section 3 Initial Inspection 32...
Страница 35: ...Section 4 Quickstart Tutorial 35 Figure 2 Wiring panel...
Страница 55: ...Section 4 Quickstart Tutorial 55 Figure 24 PC200W View data utility...
Страница 78: ...Section 5 System Overview 78...
Страница 80: ...Section 6 CR800 Specifications 80...
Страница 95: ...Section 7 Installation 95 Figure 35 DevConfig OS download window Figure 36 Dialog box confirming OS download...
Страница 104: ...Section 7 Installation 104 Figure 43 Include File settings via DevConfig Figure 44 Include File settings via PakBusGraph...
Страница 267: ...Section 7 Installation 267 Figure 84 Running average signal attenuation...
Страница 268: ...Section 7 Installation 268...
Страница 384: ...Section 8 Operation 384 Figure 113 Using the keyboard display...
Страница 385: ...Section 8 Operation 385 8 8 1 Data Display Figure 114 Displaying data with the keyboard display...
Страница 387: ...Section 8 Operation 387 Figure 116 Real time custom...
Страница 388: ...Section 8 Operation 388 8 8 1 3 Final Storage Tables Figure 117 Final storage tables...
Страница 389: ...Section 8 Operation 389 8 8 2 Run Stop Program Figure 118 Run Stop Program...
Страница 390: ...Section 8 Operation 390 8 8 3 File Display Figure 119 File display...
Страница 396: ...Section 8 Operation 396...
Страница 402: ...Section 9 Maintenance 402...
Страница 450: ...Section 11 Glossary 450...
Страница 504: ...Appendix A CRBasic Programming Instructions 504...
Страница 526: ...Appendix B Status Table and Settings 526...
Страница 530: ...Appendix C Serial Port Pinouts 530...
Страница 536: ...Appendix E FP2 Data Format 536...
Страница 550: ...Appendix F Other Campbell Scientific Products 550...
Страница 564: ...Index 564 WriteIO 464 Writing Program 108 X XML 448 XOR 473 Y Y intercept 141 142 Z Zero 155 166 Zero Basis 151...
Страница 565: ......