Apera Instruments DO8500 User manual

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DO8500
Portable Optical Dissolved Oxygen Meter
Instruction Manual
APERA INSTRUMENTS (Europe) GmbH
www.aperainst.de
v1.2

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Table of Contents
1Overview..............................................................................................................................- 3 -
1.1 Luminescent optical sensor. ..........................................................................................- 3 -
1.2 Intelligent Instrumentation..............................................................................................- 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 .................................................................................................................- 10 -
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 .............................................................................................- 12 -
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..............................................................................- 19 -
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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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 and 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 and membranes are present in the meter; no warm-up 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, along with H2S and NH4 and 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 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 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 storage sleeve, and
keep the sponge in moist, so that the fluorescent cap will not dry out. If the
sponge is dry 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 article 4.2), otherwise it may
cause unstable measurements or slow response.
Before get readings or perform other operations, wait about 30 seconds after
meter is powered on.

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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)℃
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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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 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
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 key 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 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
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 LCD screen as
shown in Figure-5, DO value: 8.18mg/L; temp. value: 25.2℃.
When salinity probe is connected and salinity is higher than 1ppt,
salinity will be displayed 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.
3.5.3 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 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 botton right 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 displayed 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 (e.g. 3 minutes) from parameter P4.1, icon
displays on LCD screen, the meter enters 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 in 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
change the recalled measuring value. Press and hold
key or key to change the recalled measuring value quickly.
3.6.4 Clear stored value
Select YES in 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 when 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 if no operation
within 20 minutes, select Off to disable this function.
Fig.-11
Fig.-10
Fig.-9

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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 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 measured value will be unstable, or the
response 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 wet. Several drops of
clean water should be added to a dry sponge (let the sponge be saturated, 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 water storage sponge is moist every 30 days or user can
store the electrode in a beaker containing water.
(C) Before the first use, unscrew the calibration sleeve to check if the sponge is wet. 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 completely dry. So the electrode should be
Fig.-12

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immersed in tap water at room temperature 25℃for 24 hours. If the water temperature
is low, soaking time is 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.
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 the probe, 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 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 instruments. When being installed, the
sensor cap must be tightened, and the interior can not be contaminated or wet.
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.

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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 ℉.
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); 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.
5.5.2 Auto 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 salinity electrode in
12.88mS/cm conductivity calibration solution, stir gentlely and
allow it to stay in the calibration solution for a while. When the
Fig.-13

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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 12.88mS/cm conductivity calibration solution to calibrate salinity. If the 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 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 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 simultaneously.
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 that the sponge in the calibration sleeve is wet. Attach the calibration 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 sleeve with water vapor. In addition, wait for the temperature to completely
stablize.
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:
Fig.-14

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(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.
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.
Measurement
7.1 When measuring, place the probe in sample solution, stir 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, 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 much more slowly
than dissolved oxygen.

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Parameter Settings
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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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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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, and then press to confirm.
2. After confirm the parameter, press key to to return to the
measurement mode.
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 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

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The port number is software connected to computer, each computer recognizes 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 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
9.1.1 Upload the stored value
Press “Download” key, all the data stored in the meter is downloaded to the computer. The
Fig.-15

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data will be listed by category.
9.1.2 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.
9.1.3 Data processing
Press “Export” key to export the stored value to Microsoft Excel file and then analyze or
print the stored data.
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 We warrant this instrument to be free from defects in material and workmanship and
agree to repair or replace free of charge, at option of APERA INSTRUMENTS (Europe)
GmbH, any malfunctioned or damaged product attributable to responsibility of APERA
INSTRUMENTS (Europe) GmbH for a period of 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.
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.