Omega DOH-10 Series User manual

User’s Guide
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DOH-10 Series
Handheld Dissolved Oxygen Meter Kit with
Optional SD Card Data Logger
TM
2

omega.com [e-mail]
Servicing North America:
U.S.A. Omega Engineering, Inc.
Headquarters: Toll-Free: 1-800-826-6342 (USA & Canada only)
Customer Service: 1-800-622-2378 (USA & Canada only)
Engineering Service: 1-800-872-9436 (USA & Canada only)
Tel: [phone] Fax: [phone]
e-mail: [email protected]m
For Other Locations Visit omega.com/worldwide
The information contained in this document is believed to be correct, but OMEGA accepts no liability for any errors it contains, and
reserves the right to alter specifications without notice.

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Professional look design portable meters with large LCD display,
Meter is designed with BNC connector compatible to any DO galvanic electrode.
Hold function, power capacity icon indicator, and automatic power off in 15 minutes and
may disable.
RFS (Recover to Factory Setting) function is included.
Built-in different temperature compensation selectable: Thermistor 30K, 10K ohm and not
25.0 (manual compensation).
DO 100% air self-calibration is convenient and simple. (Calibrated both Saturated DO / zero
DO (Na2SO3) before shipment)
Compact DO electrodes supplied with 3M cable and membrane cap, electrolyte.
Galvanic electrodes do not require long "warm up" time as polarographic type electrodes (Polarization is required
about 10-15 minutes).
Applications: Aquariums, Bio-reactions, Environmental testing (lakes, streams, oceans), Water / Wastewater
treatment, Wine production
Tripod receptacle mountable design for long time monitoring purposes.
1. Meter
2. Battery-AAA x 3 pcs
3. Electrode x 1pcs (DO Galvanic type)
4. Black carrying case
5. Electrolyte (0.5M NaOH) x1
6. Membrane cap x 1
7. Membrane x 10pcs
8. Red sandpaper (for polishing DO electrode)
9. 8G SD card (DOH-10-DL only)
10. Calibration certificate
Membrane
Model DOH-10 DOH-10-DL
Data Hold Freeze the display readings.
Meter dimension 175mm x 58mm x 32mm (With BNC connector)
Power supply AAA batteries x 3 pcs / 9V AC/DC (Option)
Parameter DO, temperature
SD sampling time
Setting range N/A
Auto
2 secs, 5 secs, 10 secs, 15 secs, 30
secs, 60 secs, 120 secs, 300secs, 600
secs, 900 secs, 1800secs, 1Hr
Manual
Manual Sample time: 0 second
Press the ADJ button once will save
data one time. @Set the sampling
time to 0 second.
Memory Card N/A SD memory size 8G
GENERAL SPECIFICATION:
SUPPLIED:
FEATURES:
11.AQM-100-PW - AC Adapter (Optional, Sold separately)

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BUTTON DESCRIPTION:
ELECTRODE INSTALLATION (BNC connector):
Temperature
0~90 ℃
Temp. accuracy
±0.5 ℃
DO (Dissolved Oxygen) Electrode
Measurement range
0~199.9% (In saturation); 0.0~20.0 mg/L
Accuracy
±2% of full scale + 1 digit
Resolution
0.1%, 0.1 mg/L
Calibration
100% Air-Saturated
Flow condition
0.3 mL/s
Dimension
12x120mm
Electrode body
ABS
Sensor type
Galvanic
ATC Temp. sensor probe
port
3.5 Ø mm diameter phone jack (10K ohm resistance)
Cable length
3 M
PWR
Power on (Press in one second) or power off (Press more than 2 seconds when
operation)
SET
Long press to enter/escape salinity/pressure setting.
Move to left digit. (Under setting mode).
Long press to save setting or calibrate the reading.
CAL
Move to right digit. (Under setting mode).
MODE Short press to change DO unit (mg/L or %).
Short press to enter pressure setting. (Under salinity setting mode.)
UNIT
Short press to change temperature unit ℃/℉.
Long press to enter temperature electrode type selection.
Short press to select NTC: Negative Temperature Coefficient)/ NOT: no remote
temperature electrode.
Long press to save setting.
HOLD
Freeze current readings (Hold icon shows at top of LCD).
Increase value. (Under setting mode).
ADJ
Decrease value. (Under setting mode).
MODE+CAL
Long press to enter DO 100% or zero calibration mode.
(Na2SO3 is required).
SET+UNIT
Recover to factory setting (under DO calibration mode).
HOLD+PWR
Disable Auto Power Off.
1. Insert the DO electrode into the top of right hole. And insert the 3.5mm Ø diameter phone jack ATC sensor plug
into the middle hole.
2. Hold the BNC connector in one hand; with the other, insert the braid into the center of the connector. Continuing
pushing the braid into the connector until it will not go in any farther.
Do this gently and slowly; do not bend the braid.
3. Turn the male BNC connector in a clockwise direction, until you cannot turn it any more.
DO ELECTRODE SPECIFICATION:

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POWER:
TEMPERATURE COMPENSATION SENSOR TYPE SELECTION:
Power supply:
1. AAA batteries x 3pcs.
Battery icon indicates when power is weak, replace with new batteries immediately as the readings now on
LCD are incorrect due to weak power.
▲Battery life: Approx. 480 hours for continuous used. .
2. Make sure electrode and meter are well connected. Don’t attempt to detach electrode from meter while in operation.
3. When meter shows erratic readings, it must be sensor failed or power is weak or calibration is required.
4. Only select one of the two electrodes while measuring the same water zone, otherwise meter appears erratic
readings. Read two parameters at the same time are only available for measuring two different water sources.
NOTE: Make sure you have connected the electrode to the meter before power on.
Momentarily press PWR button to turn on the meter, press and hold PWR button to turn off meter.
NOTE:
For each operation, make sure you are using fresh batteries, same brand, same power of batteries is also required,
otherwise ,LCD shows erratic readings and leakage may occur. Warranty is void if not follow the notices. (Note：
Remove batteries when not use！)
Power-off switch: When the meter is turned off, the internal CPU does not shut down completely, it will keep detecting
the buttons per milliseconds. Letting meter know if the user wants to activate the meter or not. It will consume the
power by each detecting, in order to save the power, you may pull down the switch.
Pull down
The switch
NOTE: Default setting is NTC 10K ohm.
There are two fixed 10Kohm and 30Kohm temperature compensation sensors for selection.
NTC 10K:
Negative Temperature Coefficient 25℃= 10 K ohm
NTC 30K: Negative Temperature Coefficient 25℃= 30 K ohm
NOTE: External temperature electrode is excluded, user can enter the temperature value by their own
temperature instrument, default temperature is 25℃,adjustable range is : 0.0℃~90.0℃
Step 1: Must select correct electrode type before measurement, otherwise the value would be incorrect.
Step 2: Long press UNIT button, the meter default is “ntc 10k”, short press UNIT button to toggle ntc 30k→not.
Step 3: Long press UNIT button again to save the setting, meter shows “SA” at the bottom of LCD and then
return to normal measurement mode.

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DO (Dissolved Oxygen) CALIBRATION:
Protective cap
Electrode type
ntc 10K (Default)
ntc 30K
not
Plug in
Temp. XX.X
Temp. XX.X
Manual temp.
Un-plugged
“ ─── ”
“ ─── ”
ATC icon
O
O
X
Calibration is necessary before measurement, please refer to the following calibration procedures:
A) Required Equipment:
1) DO electrode.
2) Sodium sulfite (Na2SO3) solution (For 0% DO calibration used).
3) Mini motor / pump in water or air bubbler or magnetic stirrer platform (For 100% Air-Saturated Water Calibration
used).
B) DO electrode installation:
NOTE: DO NOT touch the sensitive membrane when using the electrode or replacing the membrane cap,
for the sweat and grease will affect the quality of membrane and decrease the rate of oxygen permeability.
1) Remove protective cap from DO sensor head.
2) Loose the membrane cap and remove it.
NOTE: We will provide 1 pc membrane cap with membrane (pic.1), if you are first time to use the membrane cap,
please skip step 2) and follow step 7) to filling in DO electrolyte solution. If you want to change membrane, please
loose the membrane cap and remove it as pic. 2. Then follow step 3) to clean the membrane cap.
Pic. 1 Pic.2
“ATC” ICON INDICATION

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3) Rinse the Membrane Module with distilled water and blot dry with a clean lab wipe.
4) Clip one membrane from white protective round paper.
5) May use tweezers to put the membrane between the membrane cap and membrane base. (See the below
picture)
6) Push the membrane cap downward gently until it won’t lose.
7) Fill the membrane cap with the DO electrolyte solution 0.5M NaOH provided. Some solution will be vented from the
overflow port. This is normal. It should be completely filled. After injecting the solution, screw the Membrane
module. Finger-tighten until snug. Do not over tighten.
8) After injected the solution, screw the Membrane Module. Finger-tighten until snug. Do not over tighten.
membrane

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9) After filling the electrolyte solution and screw the membrane cap, please find the insulation tape to seal the
seam of the sensor head to reduce solution leakage, please refer to the picture below:
Insulation tape
10) Check the membrane module to see whether there are air bubbles in it. If found there are air bubbles, knock on the
membrane cap carefully to dispel them.
11) Inspect the membrane to ensure that the inner cathode element contacts the membrane. The membrane must be
taut, without wrinkles or imperfections. <If wrinkles are found, please follow 2) to change the membrane.
12) Connect DO electrode with Meter DO BNC connector.
13) Rinse the assembled electrode with distilled water and blot dry with a clean lab wipe.
C) DO calibration C-1) or C-2) or C-3) :
There are three ways to do the DO calibration, for common and convenient way, follow c-1.
For more accurate measurement, follow c-2 and c-3 with necessary devices and solution in laboratories.
NOTE: First doing zero DO calibration and then doing 100% air-saturated water calibration.
C-1) 100% Water-Saturated Air Calibration: (Convenient for self-calibration, common used)
1) Connect the electrode to the meter.
2) By positioning the sensor in air-saturated water (air is directed through water until the water is saturated
with it). The illustration below is a representation of the conditions in air- saturated water.
3) Press and hold MODE+CAL buttons to enter calibration mode, screen shows “DO %100” then press and hold
SET button to save and screen shows “SA” to complete calibration. Press and hold MODE+CAL buttons, screen
shows “ESC” momentarily and return to normal measurement mode.

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SALINITY CORRECTION
BAROMETRIC PRESSURE SETTING:
C-2) Zero Dissolved Oxygen Calibration: (Laboratory calibration with Na2SO3 powder)
NOTE: Generally need to do zero oxygen calibration in the situation of replacing
new electrode, replacing membrane cap, and long time without using. To do zero dissolved
oxygen calibration by the following steps:
1) Connect the electrode to the meter.
2) Use the beaker by dissolving approximately 10 grams of Na2SO3 in 500 ml of
distilled water.
3) Place the electrode in the Na2SO3 solution and wait for the reading to stabilize,
press and hold MODE+CAL buttons to enter calibration mode, press MODE+ADJ+UNIT buttons
again to enter “DO %0.0” mode, then press and hold SET button to save and screen shows “SA” to complete
calibration.
Press and hold MODE+CAL buttons, screen shows “ESC” momentarily and return to normal measurement
mode
C-3) 100% Air-Saturated Water Calibration: (Laboratory calibration with stirrer)
1) Connect the electrode to the meter.
2) Pour 100ml deionized water into a 150mL beaker. Use an air bubbler or some
type of aerator to bubble air through the water while stirring for 20 minutes until
the water becomes completely saturated with air.
3) Place the electrode in the air-saturated water and wait for the reading to stabilize,
press and hold MODE+CAL buttons to enter calibration mode, screen shows “DO %100”, then press and hold SET
button to save and screen shows “SA” to complete calibration. Press and hold MODE+CAL buttons, screen shows
“ESC” momentarily and return to normal measurement mode.
Due to the solution contains significant concentration of salinity affects the read out values of DO.
Thus, to correct salinity value is required in order to get the accurate DO reading.
(Refer to page 8, CHART 1. for reference). Use a salinity meter to get the salt concentration reading.
1) To enter the known salinity value by long press SET button and the screen shows “SAL”.
HOLD: ↑to increase ADJ: ↓to decrease
SET: ← to left digit CAL: → to right digit
Adjustable range is 0 to 45.2 ppt.
2) After setting completed, press and hold MODE button to save setting, screen shows “SA”
to complete setting. To escape the setting by press and hold SET button, screen shows
“ESC” and return to normal measurement mode.
If you are performing measurements at an altitude different from sea level 760 mmhg
(default value). It is important to enter correct barometric pressure as barometric
pressure affects DO values. (Refer to page 9, CHART 2. for reference)
1) To enter the known pressure value by long press SET button and the screen shows “SAL”.
Then, press MODE button again to switch to the pressure setting mode, screen
shows “P”.
HOLD: ↑to increase ADJ: ↓to decrease

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DO MEASUREMENT
FREEZE READINGS:
CHANGE DO UNIT to mg/L or %:
CHANGE TEMPERATURE UNIT to ℃or ℉:
AUTO POWER OFF:
RECOVER FACTORY SETTING
SET: ←to left digit CAL: →to right digit
Adjustable range is 400 to 850 mmHg.
2) After setting completed, press and hold MODE button to save setting, screen shows “SA” to
complete setting. To escape the setting by press and hold SET button, screen shows “ESC” and
return to normal measurement mode.
1) Make sure that the electrode has been calibrated.
2) Immerse the tip of the electrode in the sample to be tested. And wait for the reading to stabilize.
3) The Dissolved Oxygen value (in mg/L or %) is displayed on the second tier of LCD and the temperature reading is
displayed on the third tier of LCD.
NOTE:
For accurate Dissolved Oxygen measurements, stir the electrode while measuring under static solution is required.
This is to ensure that the oxygen-depleted membrane surface is constantly replenished.
A moving stream will provide adequate circulation.
Freeze the current readings of DO and temperature readings by press HOLD button, then icon “Hold” will appear on the
top left of screen.
Short press MODE button to toggle mg/L or %.
Short press UNIT button to toggle ℃or ℉.
Meter will turn off automatically in 15 minutes when no use, to disable auto power off function by pressing HOLD and
PWR buttons, “n” momentarily shows on screen, now meter is at non-sleep mode, then turns to normal measurement,
Meter default auto power off.
Recover factory setting is required at the situation of replacing with a new electrode. Strongly recommend to do RFS
function under both DO100% and Zero % modes. See below steps:
Step 1:
Long press MODE+CAL buttons to enter DO 100% , by pressing and holding SET+UNIT buttons, screen will show “rFS”
momentarily, screen turns to normal measurement mode.
Step 2:
Long press MODE+CAL buttons by passing DO100%, press MODE button to enter zero % mode, by pressing and holding
SET+UNIT buttons, screen will show “rFS” momentarily, screen turns to normal measurement mode.