PASCO PS-3517 User manual

Instruction Sheet
012-15719A
Carbon Dioxide ISE Probe
PS-3517
3
2
456
Internal
Glass
Electrode
Notch
Key Pin
Cap
Tape
Threaded
area
Boot
1
Cover
DO NOT let
the BNC
connector at
the top of
the unit get
wet.
Included Equipment Item Included Equipment Item
Carbon Dioxide ISE Electrode Body (2) 1 CO2 Standard Solution 1000 ppm 4
Carbon Dioxide ISE Internal Electrode 2 CO2 Reference Fill Solution 5
BNC Male-to-Female Cable 3 CO2 Ionic Strength Adjuster (ISA) 6

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Carbon Dioxide ISE Probe Introduction
2012-15719A
Introduction
This Carbon Dioxide Ion Selective Electrode (ISE) Probe
is a gas-sensing electrode that allows fast, simple, eco-
nomical, and accurate measurement of dissolved CO2 in
aqueous solutions.
Technology: Replaceable Electrode Body with PVC
Membrane
Overview
Required Equipment
• PASCO Wireless pH/ISE/ORP Sensor (PS-3204)
or
• PASPORT High Precision pH/Temperature with
ISE/ORP Amplifier (PS-2107) with a PASCO
interface (see www.pasco.com for information)
or
• Ion meter or pH/mV meter
• PASCO data collection software (see
www.pasco.com)
• Wash bottle filled with distilled or de-ionized water
• pH Buffer Solution 4.01*
• pH Buffer Solution 7.00*
• Lab wipes
• Magnetic Stirrer with Stir Bar
• Clean beakers**
(*SC-2321 pH Buffer Capsule Kit)
(**SE-7287 100 mL Beakers (12 pack) or SE-7288 1000
mL Beakers (6 pack)
Included Required Solutions*
• Reference Fill Solution
• 1000 ppm Carbon Dioxide Standard Solution
• Ionic Strength Adjuster (ISE)
(*For replacement items, see the Technical Support sec-
tion at the end of this document.)
Electrode assembly
Important. Please read these instructions before assem-
bling the Carbon Dioxide ISE Probe
1. Carefully remove the internal glass electrode from
the box. Remove the boot, which covers the tip of
the internal glass electrode. Keep the boot for later
use.
• Note: Soaking the internal glass electrode in internal
filling solution or pH 4.01 buffer for at least 1 hour
before proceeding with the following steps will
ensure fast response.
2. Remove an electrode body from the box. Using the
solution provided, fill the electrode body with about
3.5 mL of Reference Fill Solution.
3. Rinse the internal glass electrode with DI water, blot
dry. Place it into the electrode body, which has been
filled with the filling solution.
IT IS VERY IMPORTANT TO MAKE SURE THAT THE
KEY PIN ON THE INTERNAL GLASS ELECTRODE
CAP MUST FIT INTO THE NOTCH AT THE TOP
OPENING OF THE ELECTRODE BODY SO THAT THE
INTERNAL GLASS ELECTRODE WILL NOT SPIN
DURING FURTHER ASSEMBLY. THE INTERNAL
GLASS ELECTRODE SPINNING DURING ASSEMBLY
WILL DAMAGE THE MEMBRANE AT THE BOTTOM
OF THE ELECTRODE BODY, WHICH IS NOT
COVERED BY THE WARRANTY.
4. Install the threaded top cap onto the threaded sec-
tion at the top of the electrode body. Tighten the cap
until snug. Do not over tighten.
Size and Material Body (Epoxy): 12 mm OD x 155
mm Length
Cap (ABS): 16 mm OD x 47 mm
Length
Range 4.4 to 400 ppm as CO2
Reproducibility ±2% of reading
Slope 52 to 60 mV at 25°C, typical
Minimum Sample 3 mL in a 30 mL beaker
pH Range Samples and standards must be
adjusted to below pH 4.00
Operating Temperature 0 to 50°C
Electrode resistance less than 1,000 megaohms
Interferences volatile weak acid (gaseous)

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PS-3517 Introduction
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012-15719A
Software Help
See the SPARKvue Help or PASCO Capstone Help for
information about collecting, displaying, and analyzing
data.
• In SPARKvue, select the HELP button in any screen
including the Home Screen.
• In PASCO Capstone, select PASCO Capstone Help
from the Help menu, or press F1.
Checking Electrode Operation (Slope)
1. Connect your electrode to the input connector on the
Wireless pH /ISE/ORP Sensor (or other measuring
device).
2. Place 100 mL of DI water into a 150 mL beaker. Add
1 mL Carbon Dioxide ISA to the DI water and stir
throughly. Check the pH of the solution with the
Wireless pH/ISE/ORP Sensor or a piece of lab pH
paper.
• The pH value must be below pH 4.0. Otherwise, add
Carbon Dioxide ISA in 1 mL increments until the pH
value is below pH 4.0.
3. Rinse the electrode with DI water, blot dry, and
place it in the beaker with the prepared solution.
• To prevent air entrapment on the membrane
surface, use an electrode holder that keeps the
electrode at a 20 degree angle.
4. Begin recording. Add 1 mL of 1000 ppm Carbon
Dioxide Standard Solution into the beaker. Stir thor-
oughly, then record the potential (E1) in mV when a
stable reading is displayed.
5. Pipet 10 mL of the same standard solution into the
beaker. Stir thoroughly. When a stable reading is
displayed, record the potential (E2) in mV.
6. The difference between the first and second poten-
tial readings, (E2-E1), is defined as the electrode
slope. The normal range for the slope is 52 to 60 mV
at 25°C.
Troubleshooting
If the electrode slope is not within the normal range
stated above, or the electrode mV reading drifts, the
Reference Fill Solution may need to be replenished.
Hold the electrode body with one hand, and then gently
pull the cable. Release the cable. Fresh fill solution will
now occupy the space between the tip of the inner glass
body and the membrane. If this procedure does not
restore electrode response, follow the steps below:
1. Check the slope of the internal glass electrode.
Remove the internal glass electrode from the
electrode body. Connect the internal glass
electrode to the Wireless pH Sensor or to a pH/mV
meter. Put the internal glass electrode in pH 7.00
buffer. The annular ceramic junction should be
immersed in the solution. Record the reading in mV
when it is stable. Remove the internal glass
electrode from pH 7.00 buffer. Rinse with DI water,
blot dry and put it in pH 4.01 buffer. Record the
reading in mV when it is stable. The reading in pH
7.00 should be 0 + 25 mV. The millivolt difference in
the two buffers should be greater than 168 mV. (If
the difference is less than 160 mV, contact the man-
ufacturer).
2. If the internal glass electrode functions properly, but
the completely assembled electrode does not
function properly in the standards, replace the Elec-
trode Body with a new one. Unscrew the Electrode
Body from the cap. Get the extra Electrode Body
from the plastic bag. Install the new Electrode Body.
Follow the procedures described in “Electrode
assembly” and “Checking electrode operation
(slope)” again.
If the electrode still does not operate properly, contact
the manufacturer.
3. Repeat "Checking Electrode Operation" procedure
again. Note: All standard solutions should be
prepared fresh. For best performance use ISA in all
solutions.
Reading a Sample with the Electrode
Various procedures may be used to determine the
concentration of a sample. The most common is the
Direct Calibration method, which is described below.
Contact PASCO's Technical Support department for
details of other methods.
In Direct Calibration a series of standard solutions of
differing concentrations is used to calibrate the
electrode. Then each sample requires only a single
measurement device reading, which is compared with
the calibration readings to obtain the sample
concentration. ISA is added to all solutions to ensure the
samples and the standards have the same ionic
strength.
Set up:
1. Prepare the electrode as described in "Electrode
Assembly" and "Checking Electrode Operation".

®
Carbon Dioxide ISE Probe Replacement Items
4012-15719A
Connect the electrode to the sensor or measuring
device. Remove the cover from the electrode body.
2. Prepare two standard solutions that differ in
concentration by a factor of ten and bracket the
expected sample concentration range. For example,
if your expected sample concentration is 50 mg/L
Carbon Dioxide, you should use a 10 mg/L low
Standard Carbon Dioxide Solution and a 100 mg/L
high Standard Solution. Standards can be prepared
in any concentration unit to suit the particular analy-
sis requirement.
• NOTE: All standard solutions should be at the same
temperature as the sample.
Measurement:
If using a measuring device with direct concentration
reading capability, see the software on-line help or the
measuring device’s instruction manual for specific
information:
1. Place 100 mL of the low standard into a 150 mL
beaker. Add 1 mL of ISA. Stir thoroughly. Check the
pH value of the solution.
2. Rinse electrode with Dl water, blot dry and place in
the beaker. Wait for a stable reading, and then
adjust the software or the measuring device to
display the value of the standard. Refer to the soft-
ware on-line help or the measuring device’s
instruction manual for the adjustment procedure.
3. Measure 100 mL of the high standard into a second
150 mL beaker. Add 1 mL of ISA and stir. Check the
pH value of the solution.
4. Rinse electrode with Dl water, blot dry and place in
the second beaker. Wait for a stable reading, and
then adjust the software measuring device to display
the value of the second standard.
5. Measure 100 mL of the sample into a 150 mL
beaker. Add 1 mL of ISA. Stir thoroughly. Check the
pH value of the standard.
6. Rinse electrode with Dl water, blot dry and place in
the sample beaker. Wait for a stable reading and the
sample concentration will be displayed on the mea-
suring device.
7. Determine the sample concentration using the data
analysis tools in the software.
Electrode Storage
Short Term (over night):
Between measurements, keep the electrode tip
immersed in a 10 ppm standard without ISA. For
low-level measurements, keep the electrode in pH 7.00
buffer between measurements. For overnight storage,
the electrode tip should be immersed in pH 7.00 buffer
solution.
Long Term
For storage over one week, or if the electrode is stored
indefinitely, disassemble completely and rinse the Inter-
nal Glass Electrode and Electrode Body with DI water.
Dry all the parts. Do not re-insert the Internal Glass Elec-
trode into the Electrode Body. Instead, cover the tip of
the Internal Glass Electrode with the original boot. Store
all the parts separately in the original box. When reas-
sembling, follow the procedure in the “Electrode Assem-
bly” and “Checking Electrode Operation” seconds.
Life Span
The PS-3517 Carbon Dioxide ISE Probe is expected to
last more than three years before it needs to be
replaced.
Replacement Items
• PS-3517 Carbon Dioxide ISE Probe
• SC-3528 Carbon Dioxide ISE Solutions: 60-mL
Standard Solution, 30-mL Reference Fill Solution,
30-mL ISA Solution
Technical Support
For assistance with any PASCO product, contact
PASCO at:
Limited Warranty
For a description of the product warranty, see the PASCO catalog.
Address: PASCO scientific
10101 Foothills Blvd.
Roseville, CA 95747-7100
Phone: [phone] (worldwide)
800-772-8700 (U.S)
Email: [email protected]
Web: www.pasco.com/support

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PS-3517 Technical Support
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Copyright
This PASCO scientific instruction sheet is copyrighted with all rights
reserved. Permission is granted to non-profit educational institutions for
reproduction of any part of this manual, providing the reproductions are
used only in their laboratories and classrooms, and are not sold for profit.
Reproduction under any other circumstances, without the written consent
of PASCO scientific, is prohibited. Rev: 10/17
Trademarks
PASCO, PASCO scientific, PASCO Capstone, PASPORT and
SPARKvue are trademarks or registered trademarks of PASCO scientific,
in the United States and/or in other countries. All other brands, products,
or service names are or may be trademarks or service marks of, and are
used to identify, products or services of, their respective owners. For more
information visit www.pasco.com/legal.
Product End of Life Disposal Instructions:
This electronic product is subject to disposal and recycling regulations that
vary by country and region. It is your responsibility to recycle your
electronic equipment per your local environmental laws and regulations to
ensure that it will be recycled in a manner that protects human health and
the environment. To find out where you can drop off your waste equipment
for recycling, please contact your local waste recycle/disposal service, or
the place where you purchased the product.
The European Union WEEE (Waste Electronic and
Electrical Equipment) symbol (to the right) and on the
product or its packaging indicates that this product
must not be disposed of in a standard waste
container.