OAKTON 35201-50 Instruction Manual

OPERATING INSTRUCTIONS

INITIAL SETUP

Your new Dissolved Oxygen Probe has a wire plug in the top vent hole to
prevent electrolyte loss during shipment. Remove wire before using.

OAKTON 35201-50

DISSOLVED OXYGEN

PROBE

INTRODUCTION

Thank you for purchasing an OAKTON Dissolved Oxygen (DO) Probe.
Your DO Probe is a galvanic electrochemistry device; that is it does not
require power from your meter or controller to generate its signal. The DO
Probe will provide a millivolt signal proportional to the concentration of
oxygen in the water. DO probes do not measure oxygen directly. They
measure the partial pressure of oxygen in the water, which is directly
proportional to the percent saturation of oxygen in the water. The
concentration (mg/L or ppm) can be calculated based upon the oxygen
solubility, temperature, salinity, and total atmospheric pressure.

Your Dissolved Oxygen Probe consists of a cathode, anode, and an
electrolyte separated from your process fluid by an oxygen permeable
membrane. The oxygen passing through the membrane reacts with the
cathode, giving up electrons, which produce an electrical current.

When used with an Oakton DO 1000 controller, connect the wires of the
DO probe as follows

Terminal Connection Wire Color

18 Temperature 1 (Pt

100)

19 Place a jumper

between terminal 18
and terminal 19.

20 Temperature 2 (Pt

100)

21 Anode (negative) Black wire

22 Cathode (positive) Red wire

Green wire

Whi te wi re

CALIBRATION WITH OAKTON DO 1000 CONTROLLER

Upon first use with an OAKTON DO 1000 controller you should match the
probe output to the controller. The procedure described below adjust the
Full scale without disturbing the remaining setup.

1. Check probe with a millivolt meter make sure that the probe produces
around 33 mV in air (PTFE membrane). If less than 25 replace
electrolyte.

2. Connect the DO probe to the controller.

3. Power up the controller. Let probe warm up and stabilize (about 5
minutes).

4. When the unit is up and in the "Measure mode", press the 'ENTER' key.

5. The unit will display 000 in the upper and SCd in the lower display.

6. using the 'UP' key, set the code to 55 and then press ENTER.

7. The unit will display 000 in the upper and SCd in the lower display
again.

8. Using the 'UP' key, set the code to 86 and press ENTER.

9. The unit will now display a 4 digit number. Press ENTER.

10. The unit now shows OFF in the upper and HCO in the lower display.
Press ENTER.

11. The unit displays 0.0 in the upper and r 2.0 in the lower display. Press
the UP and DOWN keys TOGETHER.

12. The unit displays 100.0 in the upper and r 2.1 in the lower display.
Press the UP and DOWN keys TOGETHER.

13. The unit will display 0% in the upper display and r 4.0 in the lower
display. Press the UP and DOWN keys TOGETHER.

14. The unit will display 100% in the upper and r 4.1 in the lower display.
Press ENTER. Make sure that the DO probe is connected. The unit
should display some A/D value of around 5500 counts. Press ENTER.

15. Press the UP and DOWN keys together. The unit will display a 5 digit
number.

16. Press the UP and DOWN keys together. The unit will again display
another 5 digit number.

17. Press the UP and DOWN keys together. The unit will perform a LCD
segment test and exit to the Measurement mode.

This c ompletes the Hardware cal for the DO full scale. The unit, if in the
DO% mode should now display a value close to 100%.

MEMBRANE MATERIALS

Two types of membranes are offered for the Dissolved Oxygen Probe. The
DO Probe is normally shipped with a PTFE (Teflon) membrane. This
membrane was selected for its durability, resistance to biological and
chemical contamination, and oxygen permeability over temperature. This
membrane reduces the error due to temperature variation from the
calibrated temperature. The PTFE membrane is recommended if your
instrument is calibrated for mg/L or ppm readout.

The HDPE membrane is also available. This membrane will provide the
same millivolt output regardless of the temperature. This membrane will
provide slightly faster response to changes in oxygen concentration. The
HDPE membrane is recommended if your instrument is calibrated for
percent saturation readout. Spare membrane kits of both types are
available. Please contact your OAKTON distributor.

MOUNTING THE PROBE

Typically, Dissolved Oxygen Probes are submersion mounted. To prevent
air bubbles from becoming trapped on the membrane and producing

erroneous readings, it is recommended the probe be mounted with the
membrane pointing slightly upward. Rigid mounting brackets can also be
used.

RE-CONDITIONING YOUR DISSOLVED OXGYEN PROBE

The DO Probe service life will vary with the biological and chemical
conditions of the water that it is in. Typically, three to six months of
continuous submersion is possible before either the membrane or
electrolyte is contaminated. If the readout of your system appear
abnormal, check the Probe for membrane or electrolyte contamination. If
the membrane has a coating on it, clean with soft cloth or tissue. If the
reading still appears abnormal, replace the membrane, O-Rings, and

1. Unsc rew the lower body from the upper body.

2. Safely dispose of the electrolyte that is a special molarity, reagent grade
Sodium Chloride solution (salt water).

3. Using the Membrane Tool, unscrew the Membrane Lock in the lower
body.

4. Remove and dispose of the membrane and its O-Ring.

5. Using a toothbrush, dish washing powder, and clean water, clean the
cathode, anode, and plastic between them. Rinse all components
thoroughly.

6. Install a new O-Ring into the lower body membrane cavity.

7. Install a new membrane into the lower body.

8. Using the Membrane Tool, screw the Membrane Lock atop the
membrane.

9. Inspect the membrane for wrinkles--replace if it is wrinkled.

10. Pour some water into the lower body and look for leakage around the

membrane--replace it if there is leakage. If no leakage, dispose of the
water.

11. Fill the lower body to its rim with fresh Electrolyte.

12. Inspect the large O-Ring between the upper and lower body. Replace

it if it appears deteriorated.

13. Screw the lower body onto the upper body. Excess Electrolyte will

squirt out of a small pressure balance hole atop the upper body. If no
electrolyte squirts out, c lear the hole of its blockage before installing
the lower body.

2