Apera Instruments DO8500 User manual

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DO8500
Portable Optical Dissolved Oxygen Meter
Instruction Manual
APERA INSTRUMENTS, LLC
aperainst.com
v1.2

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Table of Contents
1Overview.........................................................................................................................- 3 -
1.1 Luminescent optical sensor................................................................................................... - 3 -
1.2 Advanced Intelligent Instrument........................................................................................... - 3 -
2Technical Specifications ...................................................................................................- 4 -
3Instructions .....................................................................................................................- 5 -
3.1 LCD Screen........................................................................................................................... - 5 -
3.2 Key Operation...................................................................................................................... - 6 -
3.3 Batteries.............................................................................................................................. - 7 -
3.4 Instrument Socket................................................................................................................ - 7 -
3.5 Display mode....................................................................................................................... - 7 -
3.6 Data storage.recall and clear................................................................................................. - 8 -
3.7 Backlighting ......................................................................................................................... - 8 -
3.8 Automatic Power-Off ........................................................................................................... - 8 -
4Optical Dissolved Oxygen Probe.......................................................................................- 9 -
4.1 Probe Structure.................................................................................................................... - 9 -
4.2 Probe Maintenance.............................................................................................................. - 9 -
4.3 Sensor Cap........................................................................................................................... - 9 -
5Preparation for Calibration ............................................................................................- 10 -
5.1 Dissolved Oxygen Units Selection ....................................................................................... - 10 -
5.2 Resolution Selection........................................................................................................... - 11 -
5.3 Temperature Unit Selection................................................................................................ - 11 -
5.4 Air Pressure Compensation ................................................................................................ - 11 -
5.5 Salinity Compensation........................................................................................................ - 11 -
6Calibration.....................................................................................................................- 12 -
6.1 Saturated Oxygen Calibration ............................................................................................. - 12 -
6.2 Zero-Oxygen Calibration..................................................................................................... - 13 -
6.3 Special Notes for Calibration............................................................................................... - 13 -
7Measurement................................................................................................................- 13 -
8Parameter Settings ........................................................................................................- 14 -
9USB Communication......................................................................................................- 17 -
10 Complete Kit..................................................................................................................- 19 -
10.1 What’s in the box............................................................................................................... - 19 -
10.2 Accessories for separate purchase ...................................................................................... - 20 -
11 Warranty.........................................................................................................................- 20 -
12 Trouble Shooting .............................................................................................................- 21 -
11 Appendix A: Oxygen Solubility Table (760mm Hg) ..........................................................- 22 -
12 Appendix B: DO % Calibration Values .............................................................................- 23 -

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1 Overview
Thank you for purchasing Apera Instruments DO8500 Portable Optical Dissolved Oxygen Meter. The
DO8500 measures dissolved oxygen in water using luminescence technology through an optical
sensor and displays data with intelligent instrumentation. Compared to conventional electrochemical
dissolved oxygen meter, the DO8500 is more accurate, stable and easier to use.
Before you use the instrument, please carefully read the instruction manual to help you properly
perform tests and maintainenance.
1.1 Luminescent optical sensor.
⚫Stability and Accuracy: Oxygen is not consumed during measurements. It is not affected by
sample flow rate and thus provides a stable measurement.
⚫Easy to Use: No electrolytes or membranes are required; frequent calibration is not
necessary.
⚫Interference-Free: Sensor cap is coated with a light-shielding layer and minimizes the impact
from external light sources. The use of non-chemical sensors helps reduce a variety of heavy
metal ions interference in the aqueous environment with H2S and NH4 and other chemical
substances.
⚫Long service life: except for mechanical deterioration (such as scratches to the light shielding
layer), the sensor cap has up to 8000 hours of service life.
⚫Easy to calibrate and maintain. Probe is equipped with a calibration/storage sleeve, which
makes calibration and maintenance more convenient and reliable.
1.2 Intelligent Instrumentation
⚫Built-in microprocessor chip, featured with Auto. Temperature Compensation, Auto. Air
Pressure Compensation, Auto. Salinity Compensation and parameter setting, auto. power off,
and low power indication.
⚫Meter meets with the requirement of international GLP standards, clock display, manual
storage and automatic timing storage. USB data output.
⚫Stable reading and automatic locking modes available.
⚫Clear large-size LCD display with white backlight.
⚫Meets IP57 waterproof rating; In addition, a rugged instrument suitcase is provided.
Special Notes
⚫Sensor cap surface coating can not withstand high temperature, so the optical
dissolved oxygen electrode can not test water with temperature over 50 ℃.
⚫When the electrode is not in use, it should be kept in the storage sleeve and the
sponge in the cap should be kept moist, so that the fluorescent cap will not dry
out. If the sponge is dried out or the probe is exposed in dry air for more than 8
hours, soak the electrode in tap water for 24~48 hours (see section 4.2),
otherwise it may cause unstable measurements or slow response.
⚫Before getting readings or performing other operations, wait about 30 seconds after
meter is powered on.

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2 Technical Specifications
Dissolved
Oxygen
Dynamic Range
(0-20.00) mg/L (ppm), (0-200.0)%
Resolution
0.01/0.1mg/L (ppm), 0.1/1%
Accuracy
±2% reading or ±0.2 mg/L,
whichever is greater
±2% reading or ±2% saturation,
whichever is greater
Response Time
≤30 s (25℃, 90% response)
Calibration Points
Saturation Point & Zero Oxygen
Temperature Compensation
Automatic, (0 to 50)℃
Air Pressure Compensation
Automatic, (60 to 120) kPa
Salinity Compensation
Manual or automatic, (0 to 45) ppt
Temperature
Range
(0 to 50.0)℃
Resolution
0.1 ℃
Accuracy
±0.5℃
Other
Data Storage
500 groups (with time and date)
Output
USB
Batteries
AA x 3 (1.5V×3)
IP Rating
IP57
Dimensions and Weight
Meter: 88×170×33 mm/313g
With case: 360×270×76 mm/1.3kg
Product Certificate
RoHs, CE & ISO9001:2015

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3 Instructions
3.1 LCD Screen
①
Measurement mode
⑨
Serial number of storage and
prompts of special display mode
②
Reading/Measured Value
⑩
M+ — Measurement to be stored
RM — Reading to be recalled
③
Timing storage
⑪
Temperature value and
prompts of special display mode
④
Date.time and prompts of
special display mode
⑫
Automatic reading lock-up
⑤
Units of date and time
⑬
ATC—Auto temperature compensation
MTC—Manual temperature compensation
⑥
Units of measurement
⑭
Stability icon of readings
⑦
Units of temperature
⑮
USB communication
⑧
Units during calibration
⑯
Low power indication
Fig.-1

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3.2 Key Operation
Short press: key press time < 2 s; Long press: key press time> 2 s.
Power on: Press to turn on. Shutdown: long press 2 seconds off.
First time use: see parameter setting P4.7 & P4.8 to set correct date and time
(as Clause 8.3)
Special notes: Before getting readings or performing other operations, wait about 30
seconds after meter is powered on.
Table - 1 Key operation and functions
Key
Operation
Functions
Short
Press
⚫When powered off, press the key to power on
⚫In measurement mode: press to turn backlight on or off
Long Press
⚫Press and hold for 2 seconds to turn off
Short
Press
⚫In measurement mode: press the key to switch unit:
%→mg/L or %→ppm
Long Press
⚫In the measurement mode:
press the key for 2 seconds to enter the calibration mode
Short
Press
⚫To cancel any operation, press to return to measurement mode
Short
Press
⚫In measurement mode: press to enter menu mode;
⚫In calibration mode: press key to calibrate;
⚫ In the menu mode: press key to confirm the parameter.
Short
Press or
Long Press
⚫In measurement mode: press to change the serial number or
press to recall the measurement value.
⚫In recall mode (RM), short press to change serial number of stored
measurement value, or long press to conduct rapidly change;
⚫In the menu mode: press the key to change the serial number or
select the parameter
Fig.-2

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3.3 Batteries
The instrument uses three AA alkaline batteries. Battery life > 200
hours (without backlight). When the display shows symbol as
shown in Figure-3, replace the battery.
3.4 Instrument Socket
The instrument sockets are protected by grey rubber sealing cap, as
shown in Figure-4.
•Eight-pin socket (right) - connect DO electrode. When
inserting the probe connector, align the notch on the
connector to the socket, and twist the nut to tighten. There is
a sealing ring between the end face of the socket and the
connector, which can effectively maintain the waterproof rating
of the socket.
•BNC socket (left) - connect salinity electrode
•RCA socket (middle) - connect temperature probe
3.5 Display mode
3.5.1 Main Display Screen
If the salinity probe is not connected or salinity is lower than 1ppt, only
the DO value and temp. value will be displayed on the screen as
shown in Figure-5, DO value: 8.18mg/L; temp. value: 25.2℃.
When salinity probe is connected and salinity is greater than 1ppt,
salinity will be displayed on the bottom right of the screen, as shown
in Figure-6, DO value: 6.97mg/L, Temp value: 25.2℃; Salinity: 32ppt,
Press to switch beteen unit of mg/L→%. Or select unit of mg/L or
ppm. Time displays on upper right of the screen.
3.5.2 Reading Stability Mode
When the measured value is stable, the LCD screen displays the icon
as shown in Figure-7. If there is no icon or it’s flashing,
it means that the reading is not stable yet, and it
should not be read, saved or calibrated.
3.5.3 Auto Lock Mode
In parameter setting P4.3 you can select the auto-lock mode (Off-On) ,
Select On to turn on automatic locking. When the reading is stable
for more than 10 seconds, the meter automatically locks the measured
value and displays the HOLD icon, as shown in Figure - 8. When auto.
locked, press to unlock. Select Off to turn off automatic lock.
Fig.-3
Fig.-7
Fig.-8
Fig.-5
Fig.-6
Fig.-4

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3.6 Data storage, recall, and clear.
3.6.1 Manual storage
When the measurement is stable, press , the meter will store
the measurement at the moment, M+ icon and storage serial number
will be displayed on the botton right of sreen, as shown in Figure-9,
First group of data was stored. If salinity probe is connected and salinity
is greater than 1 ppt, press , M+ icon and storage serial number
will be displayed for 2 seconds, then salinity
value displays on buttom right continously. As shown in Figure-6
3.6.2 Automatic timing storage
Set the automatic timing storage mode (e.g. 3 minutes a.k.a 00:03) in parameter P4.1, if
displays on screen, the meter enters the auto. timing storage mode.
If you press , starts flashing and the first measurement is
stored. After 3 minutes, the 2nd measurement will be stored
automatically.
See Figure-10 the meter stores eight measurements automatically.
Press again, stops flashing and the meter stops
the auto. timing storage. In auto. timing mode, manual storage does
not work. Set time to 00:00 in parameter P4.1 to exit from the auto. timing storage mode.
3.6.3 Recall stored value
In the measurement mode, press to recall the last stored
measurement. See Figure 11: Pressing or to
change the recalled measurement. Press and hold
or to change the recalled measurement quickly.
Press to go back to measurement mode.
3.6.4 Clear stored value
Select YES in parameter P4.4 to clear all stored values.
3.7 Backlighting
The Instrument’s LCD screen has a white backlight suitable for use in dark environments.
Turning on the backlight will consume more power. There are two backlighting modes, On
and Off, which you can select in the parameter setting P4.5. If On is selected, short press
, the backlight will stay on for one minute then automatically shuts off. If Off is selected,
press , the backlight will stay on and won’t turn off unless is pressed again.
3.8 Automatic Power-Off
In the parameter setting P4.6, you can set the auto. power off function (On-Off), select On
Fig.-11
Fig.-10
Fig.-9

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to turn on auto power off function, the instrument will shut down automatically if no operation
within 20 minutes, select Off to disable this function, meaning the meter won’t power off until
the user manually turn it off.
4 Optical Dissolved Oxygen Probe
4.1 Probe Structure
The DO803 optical dissolved oxygen probe has a cable length of 3m and a built-in
temperature sensor for automatic temperature compensation. The electrode structure is as
shown in Figure.-12
1. Bottom cover of the calibration sleeve
5. Locking cap
2. Sponge for water storage
6. Optical DO electrode
3. Sensor cap
7. O-ring
4. Calibration/storage sleeve
Immersion line:
The test sample should be above this line
4.2 Probe Maintenance
The sensor cap of the optical DO electrode must be kept in a moist environment. If the
surface coating of the sensor cap dries out, the reading will be unstable, or the response
rate will be slow. The electrode calibration sleeve is used to store the probe.
(A) Short-term storage (less than 30 days): The probe head is kept in the calibration
sleeve. Always keep the sponge inside the calibration sleeve moist. Several drops of
clean water should be added to a dry sponge (let the sponge be damp, but not
dripping), and tighten the lock cap, so that the sensor cap is kept in the moist-
saturated air.
(B) Long-term storage (greater than 30 days): The probe head is kept in the calibration
sleeve. Check whether the storage sponge is moist every 30 days or user can store
the electrode in a beaker containing clean water.
Fig.-12

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(C) Before the first use, unscrew the calibration sleeve to check if the sponge is damp. If
the sponge is dry or if the electrode is exposed to dry air for more than 8 hours, the
surface coating of the sensor cap may be dried out. So the electrode should be
soaked in clean water at room temperature for 24 hours. If the water temperature is
low, soaking time should be 48-72 hours.
(D) The sponge can not be allowed to get stained or moldy, otherwise it will consume or
produce oxygen. If stained or moldy, please replace it immediately (some back-up
sponges are included in the kit).
4.3 Sensor Cap
(A) The sensor cap is a key part of the optical DO probe. The surface coating of the cap
cannot be scratched or mechanically worn. Otherwise, the service life of the sensor
cap will be reduced or the probe will be damaged. Please pay special attention to it
when using the probe.
(B) The surface coating of the sensor cap cannot withstand high temperature, so the
optical DO probe can not be tested in water above 50˚C/122˚F.
(C) If the surface of the sensor cap is contaminated, please do not use alcohol or organic
solvents to clean, otherwise it may damage the probe. It can be gently wiped with a
soft clean cloth. To disinfect the probe, immerse it in 3% hydrogen peroxide for 15 to
30 minutes and then rinse off with clean water.
(D) The sensor cap has a service life of more than 8000 hours. When the probe is not
being used, the service life will not be reduced, so the actual use time of the sensor
cap is far more than a year. The major factor affecting the service life of the sensor
cap is the surface coating being damaged under external force. So the key is to
protect the sensor cap from external damage.
(E) If the sensor cap is damaged or deteriorated, users need to purchase a new one.
Every new cap has a set of calibration codes which need to be input into the
instrument. The specific input method will be described in the instruction manual of
sensor cap.
(F) Users should not take off the sensor cap when it is not in use. Nor should one swap
the caps from different instruments. When being installed, the sensor cap must be
tightened, and the interior can not be contaminated or wet.
5 Preparation for Calibration
5.1 Dissolved Oxygen Units Selection
Dissolved oxygen unit displays in two formats: mg/L and %, and ppm and %. Press to

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switch between mg / L and %, or ppm → %. Users can choose mg / L or ppm in parameter
setting P3.1, but only percentage (DO%) is displayed in calibration mode.
5.2 Resolution Selection
The resolution unit can be selected in parameter setting P3.2: 0.01 or 0.1mg/L (ppm), After
setting, the meter will display resolution of 0.1 or 1 in according to %.
5.3 Temperature Unit Selection
The temperature unit can be selected in parameter setting P4.2: ˚C or ˚F.
5.4 Air Pressure Compensation
The instrument has automatic air pressure compensation function. The air pressure has
been calibrated before the product left the factory. So in general users do not have to
calibrate air pressure any more. If necessary, calibrate it according to standard value
measured by aneroid barometer. Refer to parameter setting P3.5 for the procedure of
aneroid barometer calibration.
5.5 Salinity Compensation
Generally, salinity of freshwater is 0 to 0.5 ppt, salinity of seawater is around 35 ppt. As the
salinity of the solution increases, the level of DO decreases. Refer to parameter setting P3.3,
for selection of auto salinity compensation or manual salinity compensation. If manual
salinity compensation selected in P3.3, please enter the parameter setting P3.4 to input
salinity value (see section 5.5.1); if auto. salinity compensation is selected, users should
connect the salinity probe, then perform calibration in parameter setting P3.4 (see section
5.5.2).

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5.5.1 Manual salinity compensation (Hnd)
(A) In parameter setting P3.3, select manual salinity
compensation (Hnd). Operation refers to P3.3.
(B) In parameter setting P3.4, input salinity value (0~45ppt),
Operation refers to P3.4.
(C) Connect DO probe to take DO measurement.
5.5.2 Automatic salinity compensation (Aut)
(A) Connect salinity probe to meter;
(B) Switch parameter setting to P3.3, select auto. salinity
compensation (Aut), Operation refers to P3.3.
(C) Switch parameter setting to P3.4, press to enter salinity
calibration mode. Submerge the salinity probe in 12.88mS/cm
conductivity calibration solution, stir gentlely and allow it to stay
in the calibration solution for a while. When the reading is stable
and displays on the LCD, press to calibrate, LCD
displays correct salinity value (the calibration procedure refer
to Figure –13). Press to return to measurement mode.
Special notes:
(A) Use 12.88mS/cm conductivity calibration solution to calibrate salinity. If the standard
solution is wrong, Err icon will be flashing at the bottom right of LCD if is pressed,
indicating invalid calibration.
(B) Since salinity calibration is done by the factory before shipment. It
is not necessary to perform salinity calibration during initial use.
Only perform salinity calibration when replacing a new electrode,
or when the electrode is unused for a long time.
(C) For auto. salinity compensation, salinity probe must be connected,
As shown in figure-14. Users can fit DO probe and salinity probe
together into the clip to measure them simultaneously.
6 Calibration
6.1 Saturated Oxygen Calibration
(A) This procedure requires the use of a calibration sleeve to allow the probe to be calibrated
in a humidity-saturated atmosphere.
(B) Check if the sponge in the calibration sleeve is damp. Attach the calibration sleeve to
Fig.-14
Fig.-13

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the probe. Tighten the locking cap. Be careful not to have water droplets on the head of
the sensor cap. Wait for 5 to 10 minutes after turning on the instrument in order to
saturate the air in the calibration sleeve with water vapor. In addition, wait for the
temperature to completely stablize.
(C) Long press to enter the calibration mode, and CAL is flashing in the upper right
corner. Wait for the stable to appear and stay on, press to finish calibration,
once 100% starts flashing, the saturated oxygen calibration is completed.
6.2 Zero-Oxygen Calibration
Zero-Oxygen calibration is only performed when a probe or sensor cap is replaced, the
probe has not been used for a long time, or users have a requirement for high accuracy in
low DO range (0 to 2.0 ppm). Zero-Oxygen calibration is done at the factory before shipment,
so it is not necessary to perform it during initial use. Zero-oxygen calibration should follow
these steps:
(A) Preparation of 100ml of oxygen-free water: in the 100ml beaker, weigh 2g of
anhydrous sodium sulfite (Na2SO3) and add 100ml of distilled or deionized water to
dissolve. Oxygen-free water is only effective within 1 hour.
(B) Put the electrode into the oxygen-free water, wait for 3 to 5 minutes after the
instrument is turned on, and wait for the temperature and DO reading to completely
stabilize. The DO reading should be very close to 0, 0.1mg/L (ppm) or so.
(C) Long press to enter the calibration mode. CAL will be flashing at the upper right
corner. Wait for a stable . Press and the zero-oxygen calibration is completed.
6.3 Special Notes for Calibration
(A) To ensure the optimal measuring accuracy, please perform the calibration at the same
temperature as your samples. It is recommended that the oxygen saturation calibration
be performed according to section 6.1 before use every day.
(B) A dried out surface coating of the sensor cap can adversely affect the stability of
measurement. Please pay special attention to this situation. See Section 4.2 (Probe
Maintenance) for details.
(C) The instrument has factory default setting function, select YES in parameter setting P3.6,
the meter will be calibrated to the theoratical value.
7 Measurement
7.1 When measuring, place the probe in your sample solution, stir quickly for a few
seconds in the solution to remove bubbles from the measuring surface of the sensor cap.
Then hold the probe still and wait for a stable measurement. The solution must be above
the immersion line of the probe.

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Note: the brief stirring of the probe in solution is only to eliminate bubbles. Unlike
conventional galvanic/polarographic electrodes, the measuring via optical dissolved
oxygen probes does not require constant stirring of the solution or flowing fluid.
7.2 Users can read the measurements when appears and stays on. Note that the
measurement time is related to temperature. When the solution temperature and the probe
temperature is close, it takes about one minute to get the readings stablized. When the
solution temperature and the electrode temperature differ a lot, it takes about 3 minutes to
reach a stable reading. This is because the reading of dissolved oxygen is heavily
influenced by temperature, and the probe senses temperature slower than dissolved
oxygen.
8 Parameter Settings
Press in the measurement mode to enter the parameter setting mode P3.0, press
to switch the menu P3.0 →P4.0; In P3.0 mode, press to enter P3.1, press to
switch submenu P3.1→P3.6; In P4.0 mode, press to enter P4.1, press to switch
submenu P4.1→P4.8. See Table 2 for details.
Table-2 Parameter Setting List
Menu
Submenu
Parameter
Code
Content
P3.0
DO
parameter
P3.1
DO Units Selection
/
mg/L—ppm
P3.2
Resolution Selection
/
0.01/0.1 mg/L(ppm)
P3.3
Salinity Compensation Mode
/
Aut—Hnd
P3.4
Salinity Compensation
(0 to 45) ppt
P3.5
Air Pressure Calibration
(60 to 120) kPa
P3.6
Back to Factory Default
No—Yes
P4.0
Basic
parameter
P4.1
Timing Storage
/
0:00
P4.2
Temp. Unit Selection
/
℃—℉
P4.3
Auto Lock
HOLD
Off—On
P4.4
Clear Storage
CLr
No—Yes
P4.5
Auto Backlight
On—Off
P4.6
Auto Power Off
On—Off

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P4.7
Adjust Date
/
/
P4.8
Adjust Time
/
/
DO Parameter setting (press or to switch)
P3.1—Dissolved Oxygen Unit (mg/L—ppm)
1. In P3.0 mode, press to enter P3.1 mode.
2. Press , mg / L flashes, press to select
mg/L → ppm, press to confirm.
3. Press to enter P3.2 mode, or press to return to
measurement mode.
P3.2—Resolution (0.01-0.1mg/L)
1.Press , 0.01 flashes, press to select
resolution (0.01-0.1mg/L), press to confirm.
2. Press to enter P3.3 mode, or press to return to
measurement mode.
P3.3—Salinity Compensation Mode (Aut-Hnd)
1. Press , Aut flashes. Press to select auto. salinity
compensation (Aut) or manual salinity compensation (Hnd);
Press to confirm.
2. Press to enter P3.4 mode, or press to return to
measurement mode.
P3.4—Salinity Compensation (0~45 ppt)
1. Press to input salinity value, when manual salinity
compensation selected in P3.3, operation refers to section 5.5.1.
2. Press to enter salinity calibration mode, when auto.
salinity compensation was selected in P3.3, operation refers
to clause 5.5.2
P3.5—Air Pressure Calibration (60 to 120 kPa)
1. Press , 101.3 flashes, according to standard pressure
value of aneroid barometer. Press or to adjust,
Press to confirm.
2. Press to enter P3.6 mode, or press to return to
measurement mode.

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P3.6—Back to Factory Default (No—Yes)
Press , No flashes, Press to select No →Yes,
Press to confirm. Meter returns to measurement mode.
No—cancel restore. Yes—restore
Basic Parameter setting (press or to switch)
P4.1—Adjust timing storage time
1. In P4.0 mode, Press to enter P4.1 mode.
2. Press ,”00” flashes, Press or to adjust minute (0~59);
Press ,”0” flashes; Press or to adjust hour (0~99);
Press to confirm;
3. Press to enter P4.2 mode, or to return to measurement
mode.
P4.2— temperature unit (℃—℉)
1. Press , ℃ flashes, Press to select ℃→℉, Press
to confirm.
2.Press to enter P4.3 mode, or to return to measurement.
P4.3—Auto Lock (Off—On)
1. Press , Off flashes,Press to select Off→On, Press
to confirm.
Off—turn off lock function; On—turn on lock function
(If reading stays stable for more than 10 seconds, it auto locks).
2. Press to enter P4.4 mode, or to return to measurement.
P4.4. – Clear all the stored value （No—Yes）
1. Press , “ No ” flashes, then press to select
between No—Yes, press to confirm
No: not delete, Yes: delete.
2. After confirming the parameter, press to enter P4.5 mode or
press to return to measurement.

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P4.5—Auto Backlight (On—Off)
1. Press , On flashes, Press to select On→Off, Press
to confirm.
On – turn on auto backlight off function,
Off – turn off auto backlight off function.
2. Press to enter P4.6 mode, or press to return to
measurement.
P4.6—Auto Power Off (On—Off)
1. Press , On flashes，Press to select On→Off，press
to confirm.
On—turn on auto power off function
Off—turn off auto power off function.
2. Press to enter P4.7 mode, or press to return to
measurement.
P4.7. – Adjust date
1. Press , “Month” flashes, then press , “Date”
flashes, then press , “Year” flashes. When the number flashes,
press or to adjust value, then press to confirm.
2. Press to enter in P4.8 mode or press to return to
measurement.
P4.8. – Adjust time
1. Press , “HH” flashes, then press , “MM” flashes.
When the number flashes, press and to adjust
time, then press to confirm.
2. After confirming the parameter, press to return to
measurement.
9 USB Communication
The meter uses “PC-Link” software with USB communication function. The port is USB.
Software interface (as shown in Figure – 15.)
① —Stored value display area
(a) Press “Download” to download the data from the meter to the computer, measuring date,
time, value and temperature and so on.
(b) Connect meter to computer, then press , or set the auto. timing storage mode. The
measuring information will be displayed on the computer through USB and will not be

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stored in the meter as shown in Figure – 15.
② — Mode and Serial Number
③ — Parameter setting information
④ — Port type and press key
The port number shows where the software is connected to the computer, each computer
recognizes a different port number, as shown in Figure – 15, the port number is COM3.
Open/Close — press this key to turn on or off software, Icon indicates that software is
activated.
Refresh — press this key to reset COM port
SyncTime — press this key to sync time with computer.
Download — press this key to download the data from the meter to the computer,
Clear — press this key to clear all the stored values.
Export — press this key to export the stored value to a Microsoft Excel file.
Exit — press this key, PC-Link program exits from the computer interface.
9.2. Run software
Load PC-Link to the computer, open “PC-Link” file, which includes PCLink software file and
driver Compressor file. Generally, users can open PCLlink file directly. If the meter can`t
be connected to software, please install the USB driver program.
Note: for 32bit OS please install "McphCdcDriverInstallationTool" file in /x86;
for 64bit OS please install "McphCdcDriverInstallationTool" file in /x64.
Fig.-15

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9.3. Connection port selection
Connect USB cable to the meter and the computer, open PC-Link program, program
interface shows in computer, press the arrow icon next to COM1, then press Open key, LCD
will display , or please confirm the port number in “ device manager” of the computer.
9.4. Software operation
9.1.1 Upload the stored value
Press “Download” key, all the data stored in the meter will be downloaded to the computer.
The data will be listed by category.
9.1.2 Storage during operation
(a) During operation, press to store or set auto. timing storage. The measuring
information is downloaded to the computer through USB and will not be stored in the
meter.
(b) The stored mode and unit during operation is the same as the data shown on the
meter. press to change.
9.1.3 Data processing
Press “Export” key to export the stored value to Microsoft Excel file for further analysis or
printing.
10 Complete Kit
10.1 What’s in the box
Content
Quantity
1.
DO8500 Portable Optical Dissolved Oxygen Meter
1
2
DO803 Optical Dissolved Oxygen Probe
1
3
Probe Calibration/storge sleeve
1
4
Conductivity Electrode 2301-3M
1
5
PC-Link Communication Software Flashdrive
1
6
USB Communication Cable
1
7
Combined electrode clip
1
8
Small Screwdriver
1
9
Carrying Case
1
10
Sponge for Water Storage (spare)
4
11
Instruction Manual
1

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10.2 Accessories for separate purchase
11 Warranty
11.1 The warranty period of the DO8500 instrument (only the instrument) is 3 years from the
date of purchase. That of DO803 optical DO probe (excluding sensor cap) is 2 years from
the date of purchase. That of DO8032 sensor cap is 1 year from the date of delivery. If the
above products or parts within the warranty period is not functional due to raw material
defects or poor manufacturing, they are free for repair or replace.
11.2 Damage and malfunction of the product caused by the following reasons are not covered
by the warranty:
(A) Fails to install, operate, or use the product in accordance with the instruction manual, or
if the product is damaged by abuse or incorrect use;
(B) The sensor cap is damaged by external force and can not work; or the electrode cable
is damaged or twisted due to external force;
(C) Fails to maintain the product in accordance with the requirements of this manual and
the industry standard process;
(D) Any unauthorized repairs, and the use of defective or incorrect components to repair the
product;
(E) Any modification of the product unauthorized by the Company.
Model
Name
DO803
Optical DO probe (3m cable，with sensor cap and calibration sleeve)
DO810
Optical DO probe (10m cable, with sensor cap and calibration sleeve)
DO8032
Sensor cap
DO8031
Calibration/Storage sleeve