PEAK INSTRUMENTS P-512 User manual

User Manual PEAK INSTRUMENTS INC
Address: 16223 Park Row, Houston, TX-77084, USA. Website: www.peakii.com. Tel: [phone]
P-512 Dissolved Oxygen Meter
User Manual
PEAK INSTRUMENTS INC
Version 1801

User Manual PEAK INSTRUMENTS INC
Address: 16223 Park Row, Houston, TX-77084, USA. Website: www.peakii.com. Tel: [phone]
CONTENTS
I. General Information....................................................................................................1
II. Specifications .............................................................................................................2
III. Device Instructions....................................................................................................3
1. Display indicators ................................................................................................3
2. Operation Keys....................................................................................................3
3. Save, view and delete data. ................................................................................4
IV. DO Measurement......................................................................................................5
1. Preparations........................................................................................................5
2. Calibration...........................................................................................................5
3. Liquid sample measurement...............................................................................6
4. Notices ................................................................................................................6
5. Parameter settings..............................................................................................7
5.1. Table of parameter setup..........................................................................7
5.2.1. Resolution setting(P1)............................................................................7
5.3. Manual temperature compensation(P2). .................................................8
5.4. Salinity compensation(P3) ........................................................................8
5.5. Air pressure setting(P4).............................................................................8
5.6. Temperature unit setting(P5)....................................................................9
5.7. Auto shutdown timer of backlight(P6)......................................................9
5.8. Auto shutdown timer of the device(P7) ...................................................9
5.9. Restore default settings(P8)....................................................................10
6. Change diaphragm cap......................................................................................10
7. Zero oxygen calibration.....................................................................................10
8. Salinity setting...................................................................................................11
9. Air pressure setting...........................................................................................11
VI. Packing List..............................................................................................................12
Appendix I Saturated content of oxygen in water with different temperature......12
Appendix II Saturated content of oxygen in water with different air pressure ......13
Appendix III Saturated content of oxygen in water with different altitude............14

User Manual PEAK INSTRUMENTS INC
Address: 16223 Park Row, Houston, TX-77084, USA. Website: www.peakii.com. Tel: [phone]
1
I. General Information
Thanks for using P-512 DO meter. In order to help you operate and maintain the
instrument properly, please read the user manual before using it. We reserve the rights
to update the manual and its parts subject to the purpose of improving the
instrument’s performance.
This instrument combines the technologies of advanced electronics, sensors and
software design, which can be used to test the dissolved oxygen, temperature and
other parameters of water solutions. This DO meter is very suitable for industrial and
mining enterprises, power plant, environment protection, etc. Especially suitable for
outdoor purpose.
This pH meter has built-in microprocessor chip with beautiful design, variable
functions and the following features:
1. Built-in microprocessor chip, with automatic calibration, automatic or manual
temperature compensation, data storage, function settings, automatic shutdown and
low voltage alarm and other intelligent functions. Easy to use.
2. Digital filtering and slip techniques are used to improve meter’s response speed and
data accuracy. The symbol of “ ” is displayed when the measured value is stable.
3. Equipped with new type of dissolved oxygen electrode and temperature probe with
automatic temperature compensation, manual salinity compensation and air pressure
compensation, which make the measurement more accurate and operation easier.
4. Polarographic electrode only needs 3-5 mins to be polarized and adopts combined
diaphragm cap design and with three additional caps, which make the cap change
much easier.
5. The circuit board adopts Surface Mounted Technology to improve the reliability of
product processing.
6. White backlit LCD screen.
7. IP57 waterproof and dustproof.

User Manual PEAK INSTRUMENTS INC
Address: 16223 Park Row, Houston, TX-77084, USA. Website: www.peakii.com. Tel: [phone]
2
II. Specifications
Dissolved oxygen
Measuring range
(0～20.00)mg/L(ppm), (0～200.0)%
Resolution
0.1/0.01 mg/L(ppm), 1/0.1%
Accuracy
Electrode:±0.10 mg/L
Instrument: ±0.40mg/L
Response time
≤30s (25℃,90% response)
Residual current
≤0.1 mg/L
Temperature
compensation
(0～99)℃(Auto/Manual)
Salinity compensation
(0～45)ppt(Manual)
Air pressure
compensation
(0～200) kPa(Manual)
Automatic calibration
Air saturated with water, water saturated with air
Electrode type
Polarographic
Other Parameters
Data Storage
150 sets
Storage Contents
Series number, measuring value, unit,
temperature and time
Power
Two pieces of AA battery
Size & Weight
165×90×32 mm/310g
Certificates
ISO9001:2000, CE
Working Conditions
Ambient Temperature
5～35℃
Humidity
≤85%
IP Rating
IP57

User Manual PEAK INSTRUMENTS INC
Address: 16223 Park Row, Houston, TX-77084, USA. Website: www.peakii.com. Tel: [phone]
3
III. Device Instructions
1. Display indicators
① Parameter mode tag
② Measurement value
③ Data storage and replay number and symbol. Indicator of special status. M+ is
symbol for data storage. RM is data replay icon.
④ Measurement unit
⑤ Temperature and unit
⑥ Stability symbol
⑦ Calibration indicators
⑧ Low voltage symbol, when the voltage is lower than 2.6V, the symbol will be shown
to remind customer for battery change.
2. Operation Keys
There are seven operating buttons
2.1. On/off button, it is used to switch on/off the device in measuring mode.
This key is not working in other modes.
2.2. Calibration key.
2.2.1. Press this button to enter calibration mode in measuring mode.
2.2.2. Press this key to back in other modes.

User Manual PEAK INSTRUMENTS INC
Address: 16223 Park Row, Houston, TX-77084, USA. Website: www.peakii.com. Tel: [phone]
4
2.3. Function key. In measuring mode, short press(less than 1.5 seconds) this
key to change measuring unit mg/L→ppm→%.
2.4. Backlight and delete key.
2.4.1. In measuring mode, short press(less than 1.5 seconds) this key to turn on or off
backlit.
2.4.2. When viewing saved data, long press(more than 5 seconds) this key to delete
saved data.
2.5. Increase and data view key. Decrease and data saving key.
2.5.1. In measuring mode, short press(less than 1.5 seconds) to save records,
short press(less than 1.5 seconds) to view saved records.
2.5.2. and are used to change parameters under setting mode.
2.6. Set and Confirm/return key
2.6.1. In measuring status, long press(more than 2 seconds) to enter parameter
settings.
2.6.2. Short press(less than 1.5 seconds) to confirm current selection in other status.
3. Save, view and delete data.
3.1. Data save. In measuring status, when the reading is stable and shows symbol ,
short press(less than 1.5 seconds) to save records, the screen will show “M+”
and storage number. The device can save 150 sets of records totally.
3.2. Data view.
3.2.1. In measuring status, short press(less than 1.5 seconds) to view the
newest saved record of the current unit, and right upper corner will show symbol “RM”.
Continue press or to replay all saved records.
3.2.2. In view status, press to return to measuring mode.
3.3. Delete data
In data viewing mode, long press (more than 5 seconds) and screen displays

User Manual PEAK INSTRUMENTS INC
Address: 16223 Park Row, Houston, TX-77084, USA. Website: www.peakii.com. Tel: [phone]
5
for two seconds, which means all saved data is deleted already and back to
measuring mode.
IV. DO Measurement
1. Preparations
1.1. Press to switch on device, then press to choose proper unit.
1.2. Check the DO electrode (see following fig.).There should not be bubbles inside the
electrode diaphragm cap (tiny bubble is OK). Otherwise, rotate off the cap and refill it
with electrolyte and install the cap back, connected to instrument and be polarized for
15 minutes.
1. Diaphragm cap
2. DO electrode
3. Anode
4. Cathode (gold film)
5. Temperature electrode
1.3. Connect the DO electrode and temperature electrode to the interfaces at the back
of instrument.
2. Calibration
2.1. Press to enter calibration mode, the screen will show “CAL” at top right
corner to indicate entering calibration mode. Put DO electrode in the air vertically for
3-5 minutes until tested value stable and display symbol “ ”, then press key
and shows 100%. If the reading is not stable, please wait for a few minutes and press
enter calibration mode until reading is table.
2.2. After the calibration, the screen will show “ ” which means 0% oxygen
calibration is done or “ ” means 100% oxygen calibration is finished.

User Manual PEAK INSTRUMENTS INC
Address: 16223 Park Row, Houston, TX-77084, USA. Website: www.peakii.com. Tel: [phone]
6
3. Liquid sample measurement
3.1. Measuring flow liquid solution(flowing speed >5cm/s). Dip the electrode into the
liquid with the temperature probe under water surface. Tilt the electrode 45°～
75°with the flow direction, shake it slightly and last 3-5 minutes until the reading is
stable.
3.2. Measuring static liquid solution. Dip the electrode into the liquid with the
temperature probe under water surface. Tilt the electrode 45°～75°with the water
surface, move it with speed more than 5cm/s and last 3-5 minutes until the reading is
stable.
3.3. Measuring low flowing speed liquid. Please refer to 3.1 and move the electrode
faster.
4. Notices
4.1. The difference between air temperature and tested solution temperature should
be less than 10℃, if the difference is too big, the electrode should be immersed in the
solution to be tested for 10 minutes. Then calibrate it according the steps mentioned
above.
4.2. Don’t turn off the instrument during use because the electrode should be
polarized and calibrated when it is turned on.
4.3. Temperature has strong impact on DO value. Because the temperature electrode
is installed in the shell and contact directly with water instead of being installed in
electrolyte inside the electrode, which will cause different ability to induce the liquid’s
temperature and need 3-5 minutes to reach a balance. So the reading time should be
more than 3 minutes, otherwise, there will be a bigger error. Especially in case of big
temperature difference between electrode and tested liquid, the reading time should
be longer.
4.4. Air pressure has great influence on DO test(see appendix II and III). This DO meter
has manual pressure compensation function, which can amend the tested value and
make sure its accuracy.
4.6. There should not be bubbles on the sensitive membrane of DO electrode,
otherwise it will impact its accuracy.
4.7. There should be not bubble (tiny bubbles are OK) in the electrolyte inside the
electrode, if yes, it will influence its response speed and test accuracy. If there are big

User Manual PEAK INSTRUMENTS INC
Address: 16223 Park Row, Houston, TX-77084, USA. Website: www.peakii.com. Tel: [phone]
7
bubbles, please remove the cap and refill electrolyte.
4.8. The membrane surface should be humid to avoid the electrolyte around cathode
becoming dry, which will influence electrode performance greatly.
4.9. Make sure the temperature probe in the electrode shell under water, or inaccurate
temperature will result in big errors to the test value.
4.10. When the instrument is abnormal, please restore it to default settings(in P8 and
make it on) and make measurement after calibrations.
5. Parameter settings
5.1. Table of parameter setup
5.2.1. Resolution setting(P1)
5.2.1. Long press to enter set mode
Then press to enter P1.
5.2.2. Press or to select resolution 0.1 or 0.01. Press to
confirm the change and back.
5.2.3. Press to enter next parameter setting or press to back to
measuring mode.
Indicator
Description
Remarks
P1
Resolution setting
0.1mg/L, 0.01mg/L
P2
Manual temperature compensation
(0-99.9)℃
P3
Salinity compensation setup
(0 - 45)ppt
P4
Air pressure compensation setup
(0.0-199.9)kPa
P5
Temperature unit setup
℃℉
P6
Backlight time closing setting
0-20min or 0 stands for this
function is not working
P7
Automatic shutdown time setting
0-20min or 0 stands for this
function is not working
P8
System restore setup
OFF or ON

User Manual PEAK INSTRUMENTS INC
Address: 16223 Park Row, Houston, TX-77084, USA. Website: www.peakii.com. Tel: [phone]
8
5.3. Manual temperature compensation(P2).
5.3.1. Press to choose P2 in mode P1,
Then press to enter P2.
5.3.2. Press or to change the temperature. Long press these keys to
change the figures continuously. Press to confirm the change and back.
5.3.3. Press to enter next parameter setting or press to back to
measuring mode.
5.4. Salinity compensation(P3)
5.4.1. Press to choose P3 in mode P2,
Then press to enter P3.
5.4.2. Press or to change salinity. Long press these keys to change the
figures continuously. Press to confirm the change and back.
5.4.3. Press to enter next parameter setting or press to back to
measuring mode.
5.5. Air pressure setting(P4)
5.5.1. Press to choose P4 in mode P3,
Then press to enter P4.
5.5.2. Press or to change the pressure value according to the standard
air pressure. Long press these keys to change the figures continuously. Press
to confirm the change and back.
5.5.3. Press to enter next parameter setting or press to back to
measuring mode.