User's Guide
ExStik
®
DO600
Dissolved Oxygen Meter
II
RECALL
Dissolved Oxygen
DO600
Introduction
Congratulations on your purchase of the ExStik
®
DO600 dissolved oxygen / temperature meter which simultaneously displays dissolved oxygen and temperature. Units of measure are % saturation, mg/l or ppm for dissolved oxygen, and °C or °F for temperature. Advanced features include Data Hold, 25 points memory, auto power off, automatic temperature compensation, salinity and altitude compensation. Careful use and maintenance will provide years of reliable service.
Meter Description
Front Panel Description
1. Battery compartment cover
1
2
3. MODE/HOLD button
4. CAL/RECALL button
5. ON/OFF button
6. Electrode Retaining Collar
7. Dissolved Oxygen Sensor
8. Bonded Membrane Cap assembly
9. Membrane & Cathode
(Note: The Electrode storage cap is not shown)
Electrode Bottom View
Cathode Membrane
LCD Display
6
7
8
9
3
4
5
RECALL
Dissolved Oxygen
DO600
II
4. Low Battery indicator
6. Reading hold indicator
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Operation
®
Powering the ExStik®
The ExStik
®
uses four (4) CR2032 Lithium Ion Batteries. Press the ON/OFF button to turn the meter on or off. If the batteries are weak, the ‘BAT’ indicator appears on the LCD. The auto power off feature shuts the ExStik
®
off automatically after approximately 10 minutes of inactivity. The auto power off feature may be temporarily disabled for convenience or for extended polarization time.
Turn-On Diagnostics
1. When the meter is turned ON, the LCD displays “SELF” and “CAL” and the meter enters into a diagnostics mode.
2. During this time the meter is recalling the User Calibration data, performing self diagnostics & initializing the circuitry.
3. After this function is complete, the meter proceeds to the normal measurement mode.
Measurements
1. Cover the electrode with the electrode cap. The sponge contained in the cap should be moistened (not soaked) with DI (distilled water) or clean tap water. display switches on and the Self Calibration utility runs (see below). The unit of measure selected when the meter was last turned OFF will be remain on the display.
3. Wait 10 minutes to 2 hours for the probe to polarize (disable auto-power off). The reading should be approx. 101.7% (saturation) after the electrode has completely polarized.
Percent (%) Saturation is one of the meter’s three units of measure. If the meter is not in this display mode, press and hold the MODE/HOLD button until % is displayed on the
LCD, release the button. The electrode is fully polarized when the readings stop drifting and settle down. If the unit does not read 101.7% then recalibration is necessary
4. Select the desired units of measure by pressing and holding the MODE/HOLD button until the proper units are shown in the display. Remove the electrode cover and place the electrode in the sample to be measured. Stir the electrode in the sample to remove any trapped air bubbles from the membrane surface. Do not submerse the electrode to the point that the sample liquid reaches the meter’s electrode collar.
5. Allow the meter time to settle to the final measurement value.
Note: The larger the difference in temperature between the electrode and the solution the longer it will take for the reading to stabilize. Stabilization time can vary from ten (10) seconds to five (5) minutes.
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Calibration
1. Calibration should be performed on a daily basis.
2. Turn the meter ON
3. Press and hold the MODE/HOLD button until % is displayed on the LCD.
4. Allow the electrode to fully polarize. (readings are stable)
5. Place the electrode cap onto the electrode. The sponge contained in the cap should be moistened (not soaked) with DI (distilled water) or clean tap water. Be sure that the electrode membrane is clean and dry or the calibration will be incorrect. Never touch the membrane, as skin oil will affect the electrode response.
6. Wait until the reading stabilizes then press and hold the CAL/RECALL button until CAL is shown in the lower display. The readings will blink “101.7” and “SA” will appear.
7. When the calibration is complete “End” will appear and then the meter will return to the normal measurement mode.
Note: The “SA” will not appear if the calibration fails.
8. Optional ’zero oxygen’ calibration: (improves measurement accuracy for very low or very high DO measurements)
Place the electrode in a zero oxygen calibration solution, such as 5% sodium sulfite, wait for stability and press the CAL/RECALL button until CAL is shown in the in the lower display. Stability in a zero solution may take many minutes, depending on electrode history.
Note : Sodium Sulfite can become deposited on the electrode and on the “coined” surface of the electrode retaining collar. The presence of the Sodium Sulfite will negatively affect future DO measurements until such a time where ALL of it is removed from the electrode.
Measurement Units
The meter can be set to measure % saturation, dissolved oxygen in mg/l, and dissolved oxygen in parts per million (ppm). To change the mode:
1. Press and hold the MODE/HOLD button for 2 seconds and the display will begin to scroll through the different units of measure :
%
saturation; D.O. in mg/l; D.O. in ppm (parts per million)
2. When the desired units are displayed, release the MODE/HOLD button and the unit will return to normal operating mode.
Note: The “HOLD” function cannot be on when changing the measurement function. If “HOLD” is displayed in the lower left corner of the display, briefly press the MODE/HOLD button to turn it off.
Temperature Units (ºF / ºC)
1. With the unit OFF, press and hold the CAL/RECALL button. the unit ON.
Salinity Compensation
1. With the unit ON, momentarily press the CAL/RECALL button twice in quick succession
(‘SAL’ is shown in the lower temperature display).
2. Momentary press the MODE/HOLD button. Each press of the MODE/HOLD button increases the compensation by 1ppt (part per thousand); the available range is 0 to 50ppt.
3. Momentarily press the CAL/RECALL button to save the compensation setting and return to the normal measurement mode.
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Altitude Compensation
1. With the unit ON, momentarily press the CAL/RECALL button twice in quick succession
(‘SAL’ is shown in the lower temperature display.
2. Press and hold CAL/RECALL again for 2 seconds to enter the Altitude Mode (‘Ald’ will be shown in the lower temperature display).
3. The factory default value is sea level. Each press of the MODE/HOLD button increases the compensation by 1000ft. The maximum value is 20 presses (20,000ft above sea level).
4. Momentarily press the CAL/RECALL button to save the compensation setting and return to the normal measurement mode.
Auto-Power OFF Feature
The auto power off feature automatically shuts the meter off 10 minutes after the most recent button press. To disable this feature, refer to the Disable Auto-Power OFF section.
Disable Auto-Power OFF Feature
With the unit ON, momentarily press the CAL/RECALL button, then quickly press and hold both the MODE/HOLD and ON/OFF buttons until ‘oFF’ is displayed. To restore the Auto Power
Off Feature (auto power OFF enable) simply turn the meter off and on again using the ON/OFF button.
Low Battery Indication
When the battery voltage falls below the operating threshold, ‘BAT’ will appear on the display.
Refer to the Maintenance section for battery replacement information.
Storing Readings
displayed on the lower display, while the main display shows the stored reading. The meter will enter the HOLD mode and the “HOLD” indicator will appear on the LCD. operation. The next time MODE/HOLD is momentarily pressed another reading is stored and so on.
3. If more than 25 readings are stored, previously stored readings (starting with reading number 1) are overwritten.
Recalling Stored Readings
1. Momentarily press the CAL/RECALL button and then with in 4 seconds momentarily press the MODE/HOLD. The last stored data point location will be displayed (1 to 25).
Each time the MODE/HOLD button is momentarily pressed the next most recently stored data point will be displayed.
2. After the last data point stored is displayed, pressing the MODE/HOLD button again returns the display to the beginning of the list. the meter to the normal measurement mode.
Clearing Stored Readings
1. With the unit ON press and hold the ON/OFF button for 4 seconds
2. When “clr” is shown in the main display the memory is cleared.
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Measurement and Display Considerations
•
The DO600 uses a polarographic sensor, which consumes oxygen at the sensing surface.
This requires a constant movement of the sample across the membrane to maintain a constant dissolved oxygen level. It is recommended that the probe be moved in the sample as the measurement is made, or if in a laboratory environment, the sample be stirred using a stir plate.
•
If the unit appears to be locked (display frozen). It is possible that the Data Hold mode has been inadvertently accessed by a press of the MODE/HOLD button (HOLD will be displayed in the bottom left of the LCD). Simply press the MODE/HOLD button again or turn the meter off and back on again.
•
If the meter does latch up and no button presses revive it, remove the batteries and restart.
•
For maximum accuracy, allow sufficient time for the temperature of the probe to reach the temperature of the sample before taking a reading. This will be indicated by a stable temperature reading on the display.
Maintenance
Battery Replacement
1. Twist off the battery compartment cover.
2. Holding the battery housing in place with a finger, pull out the battery carrier using the two small tabs.
3. Replace the four (4) CR2032 batteries observing proper polarity.
4. Replace the battery carrier, reattach the battery compartment cap and tighten securely.
Electrode Replacement
1. To remove the electrode, first turn the instrument OFF and then unscrew and remove the electrode retaining collar. (turn the collar counter-clockwise to remove).
2. Gently rock the electrode from side to side, pulling it away from the meter until it disconnects.
3. To attach an electrode, align the positioning “keys” on the electrode and the main body housing and then carefully push the electrode into the meter socket until it is fully seated.
4. Tighten the electrode retaining collar firmly enough to seal the electrode with the meter.
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DO Bonded Membrane Cap replacement
Important Note : Do not touch the membrane as skin oils will interfere with the oxygen permeability rate of the membrane. Use caution when replacing the bonded cap.
1. It is recommended that the electrode remain attached to the meter during this replacement process.
2. To remove the bonded cap from the electrode, unscrew the cap firmly and carefully counter-clockwise from the electrode (see diagram below).
3. Discard the used cap. Please Note: The installation of a bonded cap causes the membrane to be tightly streched over the cathode. Once a bonded cap is removed reinstallation is not possible as the membrane will no longer be properly streched over the cathode.
4. Rinse the old electrolyte solution from the Cathode and Anode before continuing.
5. Use the supplied Polishing Strips to clean, polish, shine, and/or remove scratches from the cathode. Be sure to moisten the cloth before polishing the cathode. Do not over-polish the sensitive gold cathode.
6. Set the new replacement bonded cap on a flat surface. Leave the cap in this position throughout the replacement process.
7. Fill the bonded cap with the electrolyte solution up to the bottom of the threads on the inside of the cap.
8. Tap the side of the bonded cap to help jar free any trapped air bubbles from the electrolyte solution.
9. Keeping the cap in a fixed position on a flat surface, carefully insert the electrode into the new bonded cap by first dipping and removing the electrode several times from the cap.
With each dip, push the electrode progressively deeper into the bonded cap. Finally, screw the electrode slowly onto the bonded cap (clockwise) until fully tightened. The dipping and removal technique minimizes the introduction of air bubbles into the electrolyte solution. Air bubbles in the electrolyte can compromise measurements.
10. During the tightening of the bonded cap, excess electrolyte solution will leak out, this is normal and desireable since it minimizes the introduction of air pockets. Clean off the excess electrolyte before use.
Clockwise to tighten
Counter-clockwise to loosen
BONDED CAP
Electrode
Anode
Cathode
Bonded Cap
Air Vents
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Specifications
Display
Membrane
Operating Temp. Range
ATC Range
Salinity Compensation
Altitude compensation
Measurement Storage
Battery Power
Low Battery Indication
Auto Power Off
Dimensions/Weight
2000 count, Dual function 3 ½ digit LCD with Bargraph,
Display size: 24 mm x 20 mm
Bonded membrane cap with threaded fitting
0 to 50°C (32 to 122°F)
0 to 50°C (32 to 122°F)
0 to 50 ppt in 1 ppt (part per thousand) increments
0 to 20,000 ft (in 1000 ft increments)
25 tagged (numbered) data sets with recall
Four (4) CR2032 button batteries
‘BAT’ appears on the LCD
After 10 minutes of inactivity (APO override available)
36 x 173 x 41mm (1.4 x 6.8 x 1.6”); 110g (3.8 oz)
% Saturation
Dissolved Oxygen
Concentration
Temperature
0 to 200.0%
0 to 20.00 mg/l
0 to 20.00 ppm
0 to 50 °C
32 to 122°F
0.1%
0.01 mg/l
0.01 ppm
0.1 °C
0.1 °F (0 to 99ºF);
1.0 °F (>100°F)
±2.0% FS (full scale)
±2% FS
±2% FS
±1.0 °C
±1.8°F
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Appendices
Troubleshooting Guide
Symptom Possible
Unit will not power on -Batteries not in place
-Dead batteries
-Battery polarity incorrect
“BAT” indicator shown on display
Unstable Readings
-Batteries are weak
-Insufficient electrolyte in probe (Air bubbles present when probe is inverted.)
-Electrolyte is depleted
Readings drift down
Slow Response
-Insufficient stirring (the probe consumes oxygen at the measuring surface, requiring constant sample movement across membrane)
-Dirty or damaged membrane
Electrode cannot be calibrated
Electrode cannot be calibrated after replacing the electrolyte and membrane cap
Sample reading is frozen
-Depleted electrolyte
-Dirty or damaged membrane
-Dirty probe (Cathode is not a shiny gold color)
-Unit is in “HOLD” mode
-Unit is locked
-Replace Batteries
-Replace Batteries
-Reorient/Replace Batteries
-Replace Batteries
-Replace electrolyte, and membrane cap assembly.
-Move probe in sample or stir sample
-Replace electrolyte and membrane cap
-Replace electrolyte and membrane cap
-Clean cathode with cleaning paper
-Release HOLD (momentarilly press Mode/Hold button)
-Remove batteries, press
ON/OFF button, replace batteries and restart
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Operational Matrix for the Model DO600
Function /
Resulting Action
On/Off
Water Saturated
Air Calibration
Zero Calibration
Power
Status
Any
On
Mode
Setting
Any
Any
Required Button Press Sequence
Momentary press of the ON/OFF button
Place Electrode in Calibration Cap
Press & hold CAL/RECALL button for 2 seconds
Store Reading
On Any Momentary press of the MODE/HOLD button
Comments
Also works with probe removed
(Cal at zero current)
Stores and holds reading “HOLD” displayed
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Re-order and Accessory Information
Part Number Description
DO600 ExStik II Dissolved Oxygen Meter
Support line (781) 890-7440
Technical support: Extension 200; E-mail: [email protected]
Repair & Returns: Extension 210; E-mail: [email protected]
Product specifications subject to change without notice
For the latest version of this User’s Guide, Software updates, and other up-to-the-minute product information, visit our website: www.extech.com
Extech Instruments Corporation, 285 Bear Hill Rd., Waltham, MA 02451