Campbell TempVue 20 SDI-12 User manual

Revision: 11/2023
Copyright ©2023
Campbell Scientific, Inc.
TempVue™20
SDI-12
PT-100 RTD Class A Precision, Digital
Air Temperature Sensor
PRODUCT MANUAL

Please read first
About this manual
Please note that this manual was produced by Campbell Scientific Inc. primarily for the North
American market. Some spellings, weights and measures may reflect this. In addition, while most
of the information in the manual is correct for all countries, certain information is specific to the
North American market and so may not be applicable to European users. Differences include the
U.S. standard external power supply details where some information (for example the AC
transformer input voltage) will not be applicable for British/European use. Please note, however,
that when a power supply adapter is ordered from Campbell Scientific it will be suitable for use in
your country.
Reference to some radio transmitters, digital cell phones and aerials (antennas) may also not be
applicable according to your locality. Some brackets, shields and enclosure options, including
wiring, are not sold as standard items in the European market; in some cases alternatives are
offered.
Recycling information for countries subject to WEEE regulations 2012/19/EU
At the end of this product’s life it should not be put in commercial or domestic refuse
but sent for recycling. Any batteries contained within the product or used during the
products life should be removed from the product and also be sent to an appropriate
recycling facility, per The Waste Electrical and Electronic Equipment (WEEE)
Regulations 2012/19/EU. Campbell Scientific can advise on the recycling of the
equipment and in some cases arrange collection and the correct disposal of it,
although charges may apply for some items or territories. For further support, please
contact Campbell Scientific, or your local agent.

Table of contents
1. Introduction 1
2. Precautions 1
3. Initial inspection 2
4. QuickStart 3
5. Overview 6
6. Specifications 7
7. Installation 8
7.1 Wiring 8
7.2 Programming 9
7.2.1 CRBasic programming 9
7.3 Siting 10
7.4 Installation in a radiation shield 11
7.5 Mount the shield 12
8. Operations 13
8.1 SDI-12 sensor measurements 13
8.2 Updating the operation system (OS) using XLOADOS SDI-12 command 15
9. Maintenance and troubleshooting 17
9.1 Maintenance 17
9.2 Troubleshooting 18
10. References 18
Appendix A. Importing Short Cut code into CRBasic Editor 19
Appendix B. SDI-12 sensor support 20
B.1 SDI-12 command basics 20
B.1.1 Acknowledge active command (a!) 21
B.1.2 Send identification command (al!) 21
B.1.3 Start verification command (aV!) 22
B.1.4 Address query command (?!) 22
Table of Contents - i

B.1.5 Change address command (aAb!) 22
B.1.6 Start measurement commands (aM!) 23
B.1.7 Start concurrent measurement commands (aC!) 23
B.1.8 Start measurement commands with cyclic redundancy check (aMC! and aCC!) 25
B.1.9 Stopping a measurement command 25
B.1.10 Send data command (aD0! … aD9!) 25
B.2 SDI-12 transparent mode 26
B.2.1 Changing an SDI-12 address 27
B.3 References 29
Table of Contents - ii

1. Introduction
TheTempVue™20 SDI-12 represents the next generation of air-temperature measurement
sensors, meeting all relevant World Meteorological Organization (WMO1) temperature
recommendations.
Designed with the customer in mind, the TempVue 20 SDI-12 easily interfaces with Campbell
Scientific or third-party data loggers and fits a wide range of active and passive solar radiation
shields. The sensor comes with a short, attached cable and terminates with an M12 connector,
which provides exceptional convenience, environmental protection, and data integrity for use in
a variety of applications. The TempVue 20 SDI-12 communicates with a data logger or RTU using
the SDI-12 protocol.
2. Precautions
lREAD AND UNDERSTAND the Safety (p. 33) section at the back of this manual.
lWhen opening the shipping package, do not damage or cut the cable jacket. If damage to
the cable is suspected, consult with a Campbell Scientific support engineer.
lAlthough rugged, the TempVue 20 SDI-12 should be handled as a precision scientific
instrument.
lDo not bend or damage the measurement tip of the TempVue 20 SDI-12 because this can
affect the measurement quality and potentially damage the sensor.
lDo not modify or attempt to repair the TempVue 20 SDI-12 unit without consulting
Campbell Scientific.
lThis temperature probe meets UKCA and EU declarations of conformity, citing
international standards applicable to the product.
lThe TempVue 20 SDI-12 should not be buried in soil or submerged in water. Refer to
www.campbellsci.com/soil-temperature or www.campbellsci.com/water-temperature for a
list of sensors that are appropriate for soil, road surface, or water temperature applications.
1WMO, 2008. See References (p. 18).
TempVue 20 SDI-12 PT-100 Class A, Precision Air Temperature Sensor 1

3. Initial inspection
lUpon receipt of the TempVue 20 SDI-12, inspect the packaging and contents for damage.
File damage claims with the shipping company.
lImmediately check package contents against the shipping documentation. Contact
Campbell Scientific about any discrepancies.
lTable 3-1 (p. 2) shows the components typically shipped with the TempVue 20 SDI-12.
Table 3-1: TempVue 20 SDI-12 components
Component Quantity Description Image
TempVue 20 SDI-
12 1 Measures air temperature
Extension cable
(ordered as an
option)
1Connects the sensor to the
data logger
Quick deploy
guide 1Provides siting, mounting, and wiring information
Shield extender 1
Allows sensor to be housed
in a 10-plate or 14-plate
radiation shield.
TempVue 20 SDI-12 PT-100 Class A, Precision Air Temperature Sensor 2

lFigure 3-1 (p. 3) shows the TempVue 20 SDI-12 and shield extender.
Figure 3-1. TempVue 20 SDI-12 and shield extender.
lRefer to Installation in a radiation shield (p. 11) for instructions about attaching the extender
tube to the TempVue 20 SDI-12 for use in longer radiation shields.
lAccessories and replacement parts are listed on the web site product page (see
www.campbellsci.com/tempvue20-sdi-12).
4. QuickStart
A video that describes data logger programming using Short Cut is available at:
www.campbellsci.com/videos/cr1000x-data logger-getting-started-program-part-3 .Short
Cut is an easy way to program your data logger to measure the sensor and assign data logger
wiring terminals. Short Cut is available as a download on www.campbellsci.com . It is included
in installations of LoggerNet,RTDAQ, and PC400.
The following procedure shows using Short Cut to program the TempVue 20 SDI-12.
1. Open Short Cut and click Create New Program.
2. Double-click the data logger model.
3. In the Available Sensors and Devices box, type TempVue 20 SDI-12. You can also locate the
sensor in the Sensors >Temperature folder. Double click the sensor model. SDI-12 Address
defaults to 0. Enter the correct SDI-12 Address for the TempVue 20 SDI-12 if it has been
changed from the factory-set default value. The temperature defaults to degree C. This can
be changed by clicking the Temperature box and selecting one of the other options.
TempVue 20 SDI-12 PT-100 Class A, Precision Air Temperature Sensor 3

4. Click on the Wiring tab. The default control terminal for SDI-12 is C1. To change to another
terminal, click the terminal name and select another terminal. Click OK after wiring the
sensor.
5. Repeat steps three and four for other sensors you want to measure. Click Next.
TempVue 20 SDI-12 PT-100 Class A, Precision Air Temperature Sensor 4

6. In Output Setup, type the scan rate, a meaningful table name, and the Data Output Storage
Interval.
7. Select the measurement and its associated output option.
8. Click Finish and save the program. If the data logger is connected to the computer, send
the program just created to the data logger.
9. If the sensor is connected to the data logger, check the output of the sensor in the data
display in LoggerNet,RTDAQ, or PC400 to make sure it is making reasonable
measurements.
TempVue 20 SDI-12 PT-100 Class A, Precision Air Temperature Sensor 5

5. Overview
The sensor consists of a wire-wrapped, four-wire Pt100 Resistance Temperature Detector (RTD)
element encapsulated in an epoxy-filled, stainless-steel housing. The thin yet robust housing,
combined with the Pt100 sensing element, provide the first true WMO-compliant sensor to meet
the 20-second step response time with an ambient wind speed of only 1 m/s (3.3 ft/s).
The TempVue 20 SDI-12 has a maximum measurement uncertainty of only 0.3 K over the entire
measurement range of –60 to +60 °C, with only 0.1 Kelvin (K) over the most common
temperature range of -40 to +40 °C.
When exposed to environments with high wind, sun, or precipitation levels, the TempVue 20 SDI-
12 must be housed in a radiation shield, such as the RAD06 6-plate shield.
Figure 5-1. TempVue 20 SDI-12 with the cable attached
Features:
lMeets WMO step change response time at 1 m/s (3.28 ft/s)
lMaintains high measurement stability over both time and temperature
lIncredibly easy to install or remove for calibration checks
lHighly durable, providing sensor element protection in even the harshest environmental
conditions
lCompatible with any SDI-12 data logger/controller including Campbell Scientific GRANITE-
series, CR6, CR3000, CR1000X, CR800-series, CR300-series, and CR1000
lAllows for cable length adjustments without the need for calibration changes
TempVue 20 SDI-12 PT-100 Class A, Precision Air Temperature Sensor 6