Apera Instruments DO8500 User manual

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

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Table of Contents
1. Overview --------------------------------------------------------------------------------------------------
2. Technical Specifications -------------------------------------------------------------------------------
3. Instructions -----------------------------------------------------------------------------------------------
3.1 LCD Screen -----------------------------------------------------------------------------------------
3.2 Key Operation --------------------------------------------------------------------------------------
3.3 Batteries ---------------------------------------------------------------------------------------------
3.4 Instrument Socket ---------------------------------------------------------------------------------
3.5 Display Mode ----------------------------------------------------------------------------------------
3.6 Data Storage.recall and clear---------------------------------------------------------------------
3.7 Backlighting ------------------------------------------------------------------------------------------
3.8 Automatic Power-Off ------------------------------------------------------------------------------
4. Optical Dissolved Oxygen Probe -------------------------------------------------------------------
4.1Probe Structure -------------------------------------------------------------------------------------
4.2Probe Maintenance ----------------------------------------------------------------------------------
4.3Sensor Cap ------------------------------------------------------------------------------------------
5. Preparation for Calibration ---------------------------------------------------------------------------
5.1 Dissolved Oxygen Units Selection ------------------------------------------------------------
5.2 Resolution Selection ------------------------------------------------------------------------------
5.3 Temperature Unit Selection ---------------------------------------------------------------------
5.4 Air Pressure Compensation ----------------------------------------------------------------------
5.5 Salinity Compensation-------------------------------------------------------------------------------
6. Calibration ------------------------------------------------------------------------------------------------
6.1 Saturated Oxygen Calibration --------------------------------------------------------------------
6.2 Zero-Oxygen Calibration --------------------------------------------------------------------------
6.3 Special Notes for Calibration ---------------------------------------------------------------------
7. Measurement ----------------------------------------------------------------------------------------------
8. Parameter Settings ---------------------------------------------------------------------------------------
9. USB Communication ------------------------------------------------------------------------------------
10. Complete Kit -----------------------------------------------------------------------------------------------
11. Warranty ----------------------------------------------------------------------------------------------------
12.Trouble Shooting -----------------------------------------------------------------------------------------
Appendix A: Oxygen Solubility Table (760mm Hg)-----------------------------------------------
Appendix B: DO% Calibration Values -------------------------------------------------------------
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1 Overview
Thank you for purchasing Sanxin DO8500 Portable Optical Dissolved Oxygen Meter. The
DO8500 measures dissolved oxygen in water using luminescence technology through an
optical sensor and displays data using advanced intelligent instrument. Compared to
conventional electrochemical dissolved oxygen meter, the DO8500 is more accurate and
stable, easier to use and most cost-effective portable optical dissolved oxygen meter.
Before you use the instrument, please carefully read the instruction manual to help you
properly use and maintain.
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 and membranes are present in the meter; no warm-up;
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, along with H2S
and NH4and other chemical substances.
Long service life. Other than 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 calibration/storage sleeve,
which makes calibration and maintenance more convenient and reliable.
1.2 Advanced Intelligent Instrument
Built-in microprocessor chip, It`s features up to auto temp compensation, auto air
pressurecompensation, auto salinity compensation and parameter setting.auto power
off, and lower power indication.
Meter meets with the requirement of international GLP standards, clock display,
manual storage and automatic timing storage.USB communication port.
Reading stable and automatic locking modes.
Clear large-size LCD display with white backlight.
Meets IP57 waterproof rating; In addition, a standard instrument suitcase is provided.
Special Notes
Sensor cap surface coating can not withstand high temperatures, so the optical dissolved
oxygen electrode can not test the water of more than 50 ℃.
When the electrode is not in use, it should be kept in the calibration/storage sleeve, and
keep the sponge in moist, so that the fluorescent cap will not dry. If the sponge was dry for
long time or an exposure of the probe for more than 8 hours in dry air, should soak the
electrode in tap water for 24~48 hours and hydration (see article 4.2), otherwise it may
cause unstable measurements or slow response.
Before get readings or do other operations, wait about 30 seconds after meter 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 ±0.2mg/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)℃
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 & ISO9001:2008

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3 Instructions
3.1 LCD Screen
①
Measurement mode icon
⑨
Serial number of storage and
prompts of special display mode
②
Reading/Measured Value
⑩
M+ —Measurement to be stored icon
RM —Reading to be recalled icon
③
Timing storage icon
⑪
Temperature value and
prompts of special display mode
④
Date.time and prompts of
special display mode
⑫
Automatic reading lock-up icon
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 icon
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 get readings or do other operations, wait about 30 seconds after
meter powered on.
Table - 1 Key operation and functions
Key
Operation
Functions
Short Press
In the shutdown mode: press the key to boot
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 anyoperation, 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 keyto confirm the parameter.
Short Press
or
Long Press
In measurementmode: press keyto 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 threeAA batteries, please use the LR6-type
alkaline batteries to ensure battery quality. Battery life > 200 hours
(no backlight). When the display shows symbol as shown in
Figure-3, replace the battery.
3.4 Instrument Socket
The instrument socket protected by grey rubber sealing cap, as
shown in Figure-4.
Eight-pin socket (right) - connect DO electrode, When inserting
the probe plug, please insert it after the notch position, and tighten
the plug nut.The end face of the socket and the plug connection
has the sealing ring, which can effectively maintain the waterproof
protection of the socket.
BNC socket (left) - connect salinity electrode
RCAsocket (middle) - connect temperature probe
3.5 Display mode
3.5.1 Main Display Screen
If don`t connect the salinity probe or salinity lower than 1ppt, only
the DO value and temp value display on the LCD screen as shown
in Figure-5, DO value: 8.18mg/L,Temp value: 25.2℃.
When connect salinity probe and salinity higher than 1ppt, salinity will
be displays on right bottom of the LCD screen, as shown in Figure-6,
DO value: 6.97mg/L, Temp value: 25.2℃.Salinity: 32ppt, Press
key to switch beteen unit of mg/L→%. Or select unit of mg/L or ppm
in parameter setting P3.1.Time displays on top right of LCD 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 icon flashing,
indicates that the measured value is not stable, the measured value
should not be read or calibrated.
3.5.3Auto 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 locking.
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 key, the meter will store
measureent value, M+ icon and storage serial number will be displayed
on right botton of LCD sreen, as shown in Figure-9, first group of data
was stored.If connect salinity probe, press key, M+ icon and
storage serial number will be displays for 2 seconds, then salinity
displays on LCD screen continously. As shown in Figure-6
3.6.2. Automatic timing storage
Set the storage timing (eg. 3 minutes) from parameter P4.1, icon
displays on LCD screen, the meter enters into the timing storage mode.
When press key, icon flashes and the first measuring value
is stored,after 3 minutes, the 2nd measuring value is stored automaticly.
See Figure-10 the meter stores eight measuring values automatically.
When press key, icon stops flashing and the meter stops
automatic storage. In automatic storage mode, manual storage does
not work.
Set time 0 from parameter P4.1 to exit from the automatic storage mode.
3.6.3. Recall stored value
In the measurement mode, press key to recall the last stored
measured value. See Figure 11: Pressing key or key to
recall successively the stored measuring value. Press and hold
key or key to recall the stored measuring value quickly.
3.6.4. Clear stored value
Select YES from parameter P4.4 to clear all stored value.
3.7 Backlighting
The Instruments LCD screen has a white backlight suitable for use in dimly lit environments.
Turning on the backlight will consume more power. There`s two backlighting mode. On and
Off, you can select in the parameter setting P4.5. Select On, press backlight will be on
for a minute then automatically shuts off. Select Off, when the key is pressed,
backlight will be on and will be off only 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 to
turn on auto power off function, the instrument will shut down automatically after last key
press within 20 minutes, select Off to disable this function.
Fig.-11
Fig.-10
Fig.-9

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4 Optical Dissolved Oxygen Probe
4.1 Probe Structure
The instruments 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 tested solution should be above this line
4.2 Probe Maintenance
When store the probe, it should be kept in the calibration/storage sleeve, and keep the
sponge in moist, so that the fluorescent cap will not dries out. This is very important.
Otherwise it may cause unstable measurements or slow response.
(A) Before the first time use, unscrew the bottom cover of calibration sleeve to check if the
sponge is wet.if water storage sponge dry, or an exposure of more than 8 hours in the
dry air, should remove the electrode at room temperature and soak the probe in tap
water for 24 hours and hydration, if the water temperature is low, the soaking time
needs 48~72 hours.
(B) Daily-storage, Insert the probe in calibration/storage sleeve, twill on the locking cap
tightly, add several drops of clean water every three days to keep the probe head wet.
(let the sponge be saturated, but not dripping), for long-term storage, users can store
the electrode in a beaker containing water.
(C) The sponge can not be allowed to get stained or moldy, otherwise it will consume or
produce oxygen. If stained or moldy, please clean immediately. There`s four
water-storage spong for back-up in complete packing kit.
Fig.-12

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4.3 Sensor Cap
(A) The sensor cap is an important part of the optical DO probe. The surface coating of the
cap cannot be scratched or mechanically worn. Otherwise, the 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 temperatures, so the
optical DO probe can not be tested in water above 50 ℃.
(C) If the surface of the sensor cap is contaminated, please do not use alcohol and organic
solvents to clean, otherwise it may damage the probe. It can be gently wiped with a soft
cloth or paper towels. To disinfect theprobe, immerse it in 3% hydrogen peroxide for 15
to 30 minutes and then rinse off with water.
(D) The sensor cap has a service life of more than 8000 hours. When the probe is not being
used, it does not "bleach" luminescence layer; in addition, the storage time will not
reduce the life of the probe, 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) The probe that comes with the instrument or purchase separately (the luminescence
cap was assembled on the probe already) can be used directly without the input of the
calibration codes. So users should not take off the sensor cap when it is not in use. Nor
should one swap the caps from different probes. 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 units displays in two forms: mg / L and %, and ppm and %. Press to
switch between mg / L →%, or ppm → %. Users can choose mg / L or ppm in parameter
setting P3.1, but only a percentage (DO%) is displayed in probe calibration.
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: ℃or ℉.

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5.4 Air Pressure Compensation
The instrument has automatic air pressure compensation function. The instrument has
been performed the air pressure calibration before it leaves the factory. So generally users
do not have to calibrate the air pressure. 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 0.5ppt, salinity of seawater is 35ppt. 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 clause 5.5.1); Or if auto salinity compensation selected, should connect the
salinity electrode, then conduct calibration in parameter setting P3.4 (see clause 5.5.2).
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 electrode to conduct measurement.
5.5.2Auto salinity compensation (Aut)
(A) Connect salinity electrode 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 DO electrode 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 key to calibrate,LCD
displays correct salinity value (the calibration procedure refer to
Figure –13). Press key to return to the measurement mode.
Special notes:
(A) Use 12.85mS/cm conductivity calibration solution to calibrate
salinity. If the the standard solution is wrong, press key. Err
icon is flashing at the right bottom of LCD, indicates invalid calibration.
Fig.-13

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(B) Since salinity calibration is done by factory before delivery, so it
is not necessary to perform salinity calibration during initial use.
Only make salinity calibration when replace with a new electrode,
or when the electrode is unused for long time.
(C) For auto salinity compensation, should connect salinity probe,
As shown in figure-14, user can fit DO probe and salinity probe
together into the clip to measure simultaneously.
6 Calibration
6.1 Saturated Oxygen Calibration
(A) This procedure requires the use of a calibration/storage sleeve to allow the probe to be
calibrated in a humidity-saturated atmosphere
(B) Check that the sponge in the calibration/storage sleeve is wet. Attach the calibration
/storage sleeve to the probe. Tighten the locking cap. Be careful not to have water
droplets on the head of the cap. Wait for 5 to 10 minutes after turning on the instrument.
Saturate the air in the calibration/storage sleeve with water vapor. In addition, wait for
the temperature to completely stablize.
(C) Long press the key to enter the calibration mode, and the CAL is flashing in the
upper right corner of the LCD. Wait for the stable icon to appear and stay, press the
key to calibrate, once the instrument displays a stable 100%, it is ready to use.
6.2 Zero-Oxygen Calibration
Zero-Oxygen calibration is only performed when a probe or sensor cap is replaced or the
probe has not been used for a long period. It is usually not necessary to conduct zero
oxygen calibration. Zero-Oxygen calibration is done by factory before shipment, so it is not
necessary to perform a zero-oxygen calibration during initial use. Zero-oxygen calibration
should follow these steps:
(A) Preparation of 100ml of oxygen-free water: in the 100ml beaker, weigh 2g anhydrous
sodium sulfite (Na2SO3) and add 100ml of pure water or tap water to dissolve.
Oxygen-free water is 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 measured value to completely
stabilize. The measured value should be very low, 0.1mg / L or so.
(C) Long press to enter the calibration mode. The upper right corner of the LCD will
flash CAL. Wait for a stable icon. Press and the zero-oxygen calibration is
completed.
Fig.-14

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6.3 Special Notes for Calibration
(A) Please note that the closer the temperature of the sample solution to the calibration
solution, the more accurate readings.So, it is recommended that the oxygen saturation
calibration to be performed according to section 6.1 before use every day.
(B) Drying of the surface coating of the sensor cap can adversely affect the stability of the
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 theory value.
7 Measurement
7.1 When measuring, place the probe in sample solution, swirl quickly in the solution for a
few seconds and rest it to remove bubbles from the measuring surface of the sensor cap.
The solution must be above the immersion line of the probe. Note that brief shaking the
probe in solution is only to eliminate bubbles. Not like conventional electrochemical
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 measured values when the icon appears and stays. Note that
the measurement time is related to temperature. When the solution temperature and the
probe temperature is close, the measurement time is about one minute. 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 much more slowly than dissolved oxygen.

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8 Parameter Settings
8.1 Press the key in the measurement mode to enter the parameter setting mode P3.0,
press the key 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
Off—On
P4.4
Clear Storage
No—Yes
P4.5
Auto Backlight
On—Off
P4.6
Auto Power Off
On—Off
P4.7
Adjust Date
/
/
P4.8
Adjust Time
/
/

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8.2 DO Parameter setting (press or to switch)
P3.1—Dissolved Oxygen Unit (mg/L—ppm)
1. In P3.0 mode, press the key to enter P3.1 mode.
2. Press the key, mg / L flashes, press the key 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 the key, 0.01 flashes, press the key 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 the key, Aut flashes.Press to select auto salinity
compensation (Aut) or manual salinity compensation(Hnd),Press
Key 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 the key to input salinity value, when manual salinity
compensation selected in P3.3, operation refers to clause 5.5.1.
2. Press the key 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 the key, 101.3 flashes, according to standard pressure
value of aneroid barometer. Press or key to adjust,
Press key to confirm.
2. Press to enter P3.6 mode, or press to return to
measurement mode.
P3.6—Back to Factory Default (No—Yes)
Press key, No flashes, Press key to select No →Yes,
Press key to confirm. Meter returns to measurement mode.
No—cancel restore. Yes—restore

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8.3 Basic Parameter setting (press or to switch)
P4.1—Adjust timing storage time
1. In P4.0 mode, Press key to enter P4.1 mode.
2. Press key,”00”flashes, Press or key to adjust minute
(0~59);Press key,”0”flashes,Press or to adjust hour
(0~99), Press key to confirm;
3. Press key to enter P4.2 mode, or key to return to
measurement mode.
P4.2—temperature unit (℃—℉)
1. Press key, ℃flashes, Press key to select ℃→℉, Press
key to confirm.
2.Press key to enter P4.3 mode, or key to return to
measurement mode.
P4.3—Auto Lock (Off—On)
1. Press key, Off flashes,Press key to select Off→On, Press
key 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 key to enter P4.4 mode, or key to return to
measurement mode.
P4.4. –Clear all the stored value （No—Yes）
1. Press key, ― No ‖ flashes, then press key to select
between No—Yes, press key to confirm
No: not delete, Yes: delete.
2. After confirm the parameter, press to enter in P4.5 mode or
press key to return to the measurement mode.
P4.5—Auto Backlight (On—Off)
1. Press key, On flashes, Press key to select On→Off, Press
key to confirm.
On –turn on auto backlight off function,
Off –turn off auto backlight off function.
2. Press key to enter P4.6 mode, or press key to return to
measurement mode.

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P4.6—Auto Power Off (On—Off)
1. Press key, On flashes，Press key to select On→Off，press
key to confirm.
On—turn on auto power off function
Off—turn off auto power off function.
2. Press key to enter P4.7 mode, or press key to return to
measurement mode.
P4.7. –Adjust date
1. Press key, ―Month‖flashes, then press key, ―Date‖
flashes, then press key, ―Year‖flashes. When the number
flashes, press key or key to adjust date, then press
key to confirm.
2. Press key to enter in P4.8 mode or press key to return to
the measurement mode.
P4.8. –Adjust time
1. Press key, ―15‖flashes, then press key, ―06‖flashes.
When the number flashes, press key and key to adjust
time, then press to confirm.
2. After confirm the parameter, press key to to return to the
measurement mode.
9USB Communication
The meter uses ―PC-Link‖ software with USB communication function.The port is USB.
9.1 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, measureing
date.time.value and temperature and so on.
(b) Connect meter to computer, then press key, or set the timing sorage function,The
measuring information will be displayed on the computer through USB, and will not be
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 is software connected to computer, each computer recognize 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 software is

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activated.
Refresh —press this key to reset COM port to COM1
SyncTime —press this key to set time of meter same 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 value.
Export —press this key to export the stored value to Microsoft Excel file.
Exit —press this key, PC-Link program exists from the computer interface.
9.2. Run software
Load PC-Link to the computer, open ―PC-Link‖ file, which inclucing PCLink software file
and driver Compressor file, Generally, open PCLlink file directly. If the meter can`t be
connected to software, please install USB driver firstly.
9.3. Connection port selection
Connect USB cable to the meter and the computer, open PC-Link program, program
interface shows in computure, press the arrow icon next to COM1, then pres Open key,
LCD will displays , or please confirm the port number in ― device manager‖ of the
computer.
9.4. Software operation
9.4.1. Upload the stored value
Press ―Download‖ key, all the data stored in the meter is downloaded to the computer. The
data will be listed by category.
Fig.-15

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9.4.2. Storage during operation
(a) During operation, press key to store or set 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 same as the data shown on the meter.
press to change.
9.4.3. Data processing
Press ―Export‖key to export the stored value to Microsoft Excel file and then analyze or
print the stored data.
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 disk
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
10.2 Accessories for separate purchase
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

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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 purchase. 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.
11.3 Product Warranty Period is the free of charge service time for the user who purchase
the product, not the service life of the instrument or the probe.