Campbell Scientific IRTS-P User Manual

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IRTS-P Precision Infrared

Temperature Senso

Revision: 9/06

Copyright © 2002-2006

Campbell Scientific, Inc.

Apogee Instruments, Inc.

Warranty and Assistance

The IRTS-P PRECISION INFRARED TEMPERATURE SENSOR is
warranted by CAMPBELL SCIENTIFIC, INC. to be free from defects in
materials and workmanship under normal use and service for twelve (12)
months from date of shipment unless specified otherwise. Batteries have no
warranty. CAMPBELL SCIENTIFIC, INC.'s obligation under this warranty is
limited to repairing or replacing (at CAMPBELL SCIENTIFIC, INC.'s option)
defective products. The customer shall assume all costs of removing,
reinstalling, and shipping defective products to CAMPBELL SCIENTIFIC,
INC. CAMPBELL SCIENTIFIC, INC. will return such products by surface
carrier prepaid. This warranty shall not apply to any CAMPBELL
SCIENTIFIC, INC. products which have been subjected to modification,
misuse, neglect, accidents of nature, or shipping damage. This warranty is in
lieu of all other warranties, expressed or implied, including warranties of
merchantability or fitness for a particular purpose. CAMPBELL SCIENTIFIC,
INC. is not liable for special, indirect, incidental, or consequential damages.

Products may not be returned without prior authorization. The following
contact information is for US and International customers residing in countries
served by Campbell Scientific, Inc. directly. Affiliate companies handle
repairs for customers within their territories. Please visit
www.campbellsci.com to determine which Campbell Scientific company
serves your country. To obtain a Returned Materials Authorization (RMA),
contact CAMPBELL SCIENTIFIC, INC., phone [phone]. After an
applications engineer determines the nature of the problem, an RMA number
will be issued. Please write this number clearly on the outside of the shipping
container. CAMPBELL SCIENTIFIC's shipping address is:

CAMPBELL SCIENTIFIC, INC.

RMA#_____
815 West 1800 North
Logan, Utah 84321-1784

CAMPBELL SCIENTIFIC, INC. does not accept collect calls.

IRTS-P Table of Contents

PDF viewers note: These page numbers refer to the printed version of this document. Use
the Adobe Acrobat® bookmarks tab for links to specific sections.

1. General Description.....................................................1

2. Specifications ..............................................................1

3. Installation....................................................................2

4. Wiring............................................................................3

5. Example Programs......................................................3

6. Maintenance...............................................................11

Figures

Tables

3-1. IRTS-P on UT018 Crossarm...................................................................2

3-2. Mounting IRTS-P to UT018 Crossarm...................................................2

5-1. Wiring for Example Programs ................................................................4

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IRTS-P Precision Infrared Temperature Sensor

1. General Description

An infrared temperature sensor (IRTS) is a non-contact means of measuring
the surface temperature of an object by sensing the infrared radiation given off.
IRTS are widely used for measurements of leaf, canopy, and average surface
temperature. With contact sensors it is difficult to avoid influencing the
temperature, maintain thermal contact, and provide a spatial average.

By mounting the infrared sensor at an appropriate distance from the target, it
can be used to measure an individual leaf, a canopy, or any surface of interest.

The IRTS-P is an infrared temperature sensor calibrated to output the signal for
the target temperature with the same output voltage as if a Type K
thermocouple were sensing the target temperature. A separate type K
thermocouple is used to measure the temperature of the sensor body. The
sensor body temperature is used to correct the target temperature for greater
accuracy.

2. Specifications

Power Requirements

Accuracy

Repeatability
Mass
Dimensions
Response Time

Output Signal

Optics
Wavelength Range
Field of View

Operating
Environment

None: self-powered

±0.3°C from -10° to 55°C (±0.1°C when
sensor body and target are at the same
temperature)

0.05°C from -10° to 55°C
Less than 100 grams

6.3 cm long by 2.3 cm diameter
Less than 1 second to changes in target
temperature
2, type K, twisted, shielded pair thermocouple
outputs (15 ft each), one for target
temperature, one for sensor body temperature.
The sensor body temperature is used to make a
correction for target temperature.
Silicon lens
6 to 14 micrometers
3:1 field of view (at 3 meters from sensor the
FOV is a 1 meter diameter circle)
Highly water resistant, designed for
continuous outdoor use; temperature range:

-10° to 55°C

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IRTS-P Precision Infrared Temperature Sensor

3. Installation

The field of view for infrared sensors is calculated based on the geometry of
the sensor and lens. However, optical and atmospheric scatter and unwanted
reflections from outside the field of view may influence the measurement.
Under typical conditions, 80 to 90 percent of the IR signal is from the field of
view and 10 to 20 percent is from the area surrounding the field of view. If the
target surface is small, for example a single leaf, try to mount the sensor close
enough that the surface extends beyond the field of view.

To obtain the desired view of the canopy or surface of interest, the IRTS-P is
often mounted separately from a met station tower. A hole threaded for a
standard tripod camera mount screw (1/4 inch diameter; 20 threads per inch)
can be used to mount the sensor to a user-supplied support.

The IRTS-P can be mounted to a Campbell Scientific tripod or tower with the
UT018 Crossarm (Figure 3-1.) A mounting kit (Stainless steel bolt, 2 washers,
and 2 nuts PN 14475) is included with the IRTS-P that can be used to attach
the sensor to the crossarm (Figure 3-2.)

FIGURE 3-1. IRTS-P on UT018 Crossarm

Tighten against sensor to fix
angle of sensor.

Nut with two lock washers
attaching bolt to the arm.

FIGURE 3-2. Mounting IRTS-P to UT018 Crossarm

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