Carbon Dioxide Gas Sensor
Introduction
2
012-14330C
NOTE: If more distance is needed between the sensor and
the interface, plug the sensor into the included Extension
Cable, and then plug the cable into the interface.
•
Insert the sensor probe into the gas sample. Allow 90
seconds for the sensor to warm up with the probe tem-
perature between 20° and 30° C.
•
Start the PASCO data collection software.
Using the PASCO Data Collection Software
•
Set up a data display (such as a Digits or Graph display)
in the software.
•
In PASCO Capstone, click one of the display templates
in the workbook page, or double-click an icon in the
“Displays” palette to open a data display.
•
In the SPARKvue sensor parameter screen, touch ‘CO2
Concentration’ to highlight it, and then touch ‘Show’ to
open a Graph display.
•
Click “Record” (in Capstone) or touch ‘Start’ in
SPARKvue to begin recording data.
CAUTION:
The sensor was not designed for use in liquids, dusty or
windy environments, or in direct sunlight. Do not place the
sensor in liquid samples such as water or beverages as this
will permanently damage the sensor. Using the sensor in
dusty or windy environments or in direct sunlight may cause
anomalous readings. The operating temperature range is
between 20° and 30°C.
NOTE
: Do not try to remove the probe from the sensor. It is
not removable.
STORAGE:
Always store the sensor in the plastic zip-lock bag to mini-
mize distorted sensor readings due to dust and dirt.
Collecting CO
2
Samples
Use the sampling bottle to collect air samples, such as an
atmospheric sample or the carbon dioxide gas produced from
germinating seeds.
To collect an atmospheric sample
Keep the bottle upright and the neck
open (without the stopper). Wait long
enough to allow atmospheric air to fill
the bottle. Insert the probe with the
stopper into the neck of the bottle. Be
sure that the stopper fits snugly into the
neck of the bottle.
To collect expired air or other
gas samples
Collect the sample in a plastic bag and
clamp the bag closed. To take a read-
ing, open the bag and immediately
place it over the probe and stopper, holding the bag tightly
around the stopper.
Sensor Calibration
Because the sensor is
factory calibrated, cali-
bration is not required
for most activities.
However, the sensor’s
characteristics may
change over time. To
restore the sensor to its
factory-calibrated
state, perform the cali-
bration using a fresh air sample.
(
NOTE
: Refer to the User’s Guide and On-Line Help for the
data collection software.)
•
Collect a sample of fresh air (400 to 450 ppm CO
2
).
•
Insert the probe with stopper into the upright sampling
bottle. Be sure that the stopper fits snugly into the neck
of the bottle.
•
Connect the sensor to a PASPORT-compatible interface.
Set up a digits displayand start recording data. Wait at
least 90 seconds for the reading to stabilize.
•
Press the Calibrate button (CAL) for 3 seconds and then
release it. The green light emitting diode (LED) will
start blinking once per second to indicate that calibration
has begun.
•
Wait approximately two minutes. When the green LED
stops blinking, calibration is finished.
•
Check that the reading in the data acquisition software is
400 ppm ±50 ppm (parts per million).
Suggested Activities
Cellular Respiration of Peas
•
Put 1/4 cup of dry pea seeds in the sampling bottle.
Insert the probe and stopper into the neck of the bottle.
•
Connect the sensor to a PASPORT-compatible interface
and start the data collection software.
Sensor
Interface
stopper
probe
LED
Calibration
Button
