PASCO PS-2148 IR Sensor - Manual (Page 2)

IR Sensor Sensor Setup
2 ®
The sensor's silicon-based thermopile encapsulated in nitrogen with a
thallium bromide-iodide (KRS-5) window has a flat spectral response
from 0.7 to 30
µm. It measures radiation intensity up to 4500 W/m 2
. An
integrated thermistor measures the temperature of the detector allowing
the user to calculate detector-emitted radiation. In conjunction with a
PASPORT interface, the IR Sensor measures and records thermopile
voltage, radiation intensity and detector temperature at up to 100
samples per second.
Sensor Setup
Connect the IR sensor to a PASPORT interface either directly, or via a
PASPORT extension cord. If you are using a computer, connect the
interface to the USB port and start DataStudio.
By default the sampling rate of the sensor is 100 Hz. To change it, go to
the Experiment Setup window in DataStudio, or the Sensors screen of
the Xplorer GLX. To set up the sensor for estimating the temperature of
objects, see “Non-contact Temperature Sensor Simulation” on page 5.
If desired, connect the sensor handle to the ¼-20 threaded connector on
the sensor. This connector can also be used with any other ¼-20 screw.
It is not always necessary to attach the shutter, but it can be useful to
control the detector temperature. Install the shutter as shown using the
included thumbscrew and washer. Or use the sensor handle in place of
the thumbscrew.
To measure net IR intensity, point the sensor at a surface or object, such
as your hand or the sun, and start data collection in DataStudio or the
PASPORT interface. In DataStudio, intensity is automatically shown in
a digits display. In DataStudio or on the Xplorer GLX the data can also
be displayed in a graph, table, or meter.*
Background
IR Radiation
All objects emit IR radiation.The radiated power per unit area of an
object is given by the Stefan-Boltzmann law:
I =
εσT 4
Where T is the objects’ absolute surface temperature, and
σ is the
Stefan-Boltzmann constant, equal to 5.670
× 10 -8
W
⋅m -2 ⋅K -4
. The
emissivity,
ε, is a property of the object’s surface and can range from 0
to 1. An object with
ε = 1 is described as a blackbody.
Sensor Handle
and Shutter
Attachment
I RL
I GH
T
PS -21 48
I RL I GH
T
PS-21 48
*Refer to the DataStudio
Help menu, or the
Xplorer GLX Users’
Guide for information on
setting up data displays.