Thermo Fisher Scientific PD 300 User Manual

Instruction Manual

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PD 300

Waterproof Hand-held pH/Dissolved Oxygen/Temperature Meter

Technolo

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68X248910

Rev.3 JUN 06

Preface

This manual serves to explain the use of the PD 300 hand-held meter.

The manual functions as a step by step guide to help the user operate the meter and as a handy

reference guide.

This instruction manual is written to cover as many anticipated applications of the meter as

possible. If there are doubts in the use of the PD 300 meter, do not hesitate to contact the nearest

Authorised Distributor.

Eutech Instruments/ Oakton Instruments cannot accept any responsibility for damage or

malfunction to the meter caused by improper use of the instrument.

The information presented in this manual is subject to change without notice as improvements are

made, and does not represent a commitment on the part of Eutech Instruments Pte Ltd/ Oakton

Instruments.

Copyright © 2000

Eutech Instruments Pte Ltd/ Oakton Instruments

All rights reserved.

Rev.3 JUN 06

TABLE OF CONTENTS

1 INTRODUCTION 1
2 DISPLAY AND KEYPAD FUNCTIONS 2

2.1 Display 2

2.2 Keypad 3

3 PREPARATION 4

3.1 Inserting the Batteries 4

3.2 Probe Information 5

4 CALIBRATION 7

4.1 Important Information on Meter Calibration 7

4.2 Temperature Calibration 8

4.3 pH calibration 9

4.4 Dissolved Oxygen Calibration 12

4.5 Dissolved Oxygen Calibration in % Saturation 13

4.6 Dissolved Oxygen Calibration in mg/L (ppm) mode 15

5 MEASUREMENT 17

5.1 Taking pH Measurements 17

5.2 Taking DO readings 21

5.3 Taking Pressure/Salinity Compensated DO measurements 23

6 HOLD FUNCTION 24
7 BACKLIT LCD 52

7.1 Using the backlit LCD 25

7.2 Adjusting the LCD brightness 25

8 ADVANCED SETUP FUNCTIONS 62

8.1 Advanced SETUP Mode Detailed Overview 26

8.2 P1.0: Viewing previous pH calibration data 30

8.3 P2.0: Viewing pH electrode data 31

8.4 P3.0: pH Measurement configuration 32

8.5 P4.0: Resetting to factory default settings (pH) 36

8.6 P1.0 (dPr): Dissolved Oxygen Parameters 37

8.7 P2.0 (OFS): Offset for % Saturation Measurement 40

8.8 P3.0 [P2.0] (CAL): Previous Calibration Information

(*Program numbers in “[ ]” are for setup in mg/L (ppm) mode. 41

8.9 P4.0 [P3.0] (ELE): Electrode Properties 42

8.10 P5.0 [P4.0] COF: Unit Configurati on 44

8.11 P6.0 [P5.0] LCd: Adjusting LCD Brightness 48

8.12 P7.0 [6.0] rSt: Resetting to Factory Default Setting (DO) 49

9 PROBE CARE AND MAINTENANCE 05

9.1 pH Electrode care 50

9.2 Dissolved Oxygen Principle 52

9.3 Probe Care and Maintenance 53

9.4 Membrane Housing Replacement 54

9.5 Membrane/O-ring Replacement (Optional Procedure) 55

9.6 Electrolyte Solution 57

9.7 DO Probe Troubleshooting Table 58

10 TROUBLE SHOOTING GUIDE 60
11 ERROR MESSAGES 61
12 SPECIFICATIONS 62
13 ACCESSORIES 63
14 ADDENDUM 1: DISSOLVED OXYGEN & METER THEORY 66
15 ADDENDUM 2: PRESSURE VS ALTITUDE TABLE 67

16 ADDENDUM 3: METER FACTORY DEFAULT SETTINGS 68
17 WARRANTY 69
18 RETURN OF ITEMS 70

Instruction Manual PD 300

1 INTRODUCTION

Thank you for selecting the PD 300 waterproof portable meter. This meter is a

microprocessor-based instrument that is designed to allow one-hand operation. It is capable of

measuring pH, Dissolved Oxygen (mg/L or % Saturation of Oxygen) and Temperature. It is

completely WATERPROOF --- and it FLOATS!

This meter has many user-friendly features ---- all of which are completely accessible through

the water-resistant membrane keypad. Your meter includes a pH electrode (EC-DA93506-

03B / 35805-23), dissolved oxygen electrode with integrated temperature sensor in a

submersible cable (EC-DOHANDY / 35640-50), maintenance kit, and instruction manual.

These items are available in a hard, plastic carrying case which makes it ideal for outdoor field

measurement. Please read this manual thoroughly before operating your meter.

Figure 1: Waterproof PD 300 Dissolved Oxygen Meter

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Instruction Manual PD 300

2 DISPLAY AND KEYPAD FUNCTIONS

2.1 Display

The LCD has a primary and secondary display.

• The primary display shows the measured pH or DO value (either in mg/L, ppm
or %, depending on units of measurement selected).

• The secondary display shows the measured temperature.

The display also shows error messages, keypad functions, and program functions. See Figure

2.

Figure 2: Full LCD Screen

1. SETUP mode indicator 7. Oxygen solubility indicator in

2. MEASurement mode indicator 8. Temperature indicator 14.Calibration indicator

3. CALibration indicator 9. pH buffer indicator 15 Function ON / OFF

4. pH indicator 10. Automatic Temperature

5. % saturation indicator 11. ERRor indicator 17 READY indicator

6. ppt indicator for input of

Salinity value.

mg/L or ppm.

Compensation indicator

12. Low battery indicator

13. Probe indicator

indicator

16 HOLD indicator

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Instruction Manual PD 300

2.2 Keypad

The large membrane keypad makes the instrument easy to use. Each button, when pressed,

has a corresponding graphic indicator on the LCD. See Figure 1. Some buttons have several

functions depending on its mode of operation.

Key Function

ON/OFF Powers meter on and off. The meter powers on in the mode that you were last using.

HOLD Freezes the measured reading. To activate, press HOLD while in measurement mode.

MODE 1. Selects the measurement parameter. Press MODE to toggle between pH; DO %

CAL/MEAS Toggles between Calibration and Measurement mode.

ENTER 1. Press to confirm your calibration values in calibration mode.

▲/▼

SETUP Takes you into the SETUP mode. This mode lets you customise meter preference and

For example, if you shut the meter off in mg/L measurement mode, the meter will be in
mg/L measurement mode when switched on. Note: The meter shuts off automatically
after 20 minutes of the last key press.

To release, press HOLD again.
NOTE: When auto endpoint feature is switched on, it automatically holds reading after 5

seconds of stability. The HOLD indicator appears on the display. Press HOLD again to
release.

saturation; and DO mg/L.

2. While in CAL mode under pH or mg/L (parts per million – ppm) measurement status,
this key will toggle between pH or mg/L (or ppm) calibration and temperature
calibration (refer to Section 4.2 in page 8).

1. In pH measurement mode, press CAL/MEAS to enter pH calibration mode.

2. In DO % saturation measurement mode, press CAL/MEAS to enter DO %

saturation calibration mode.

3. In DO mg/L (or ppm) measurement mode, press CAL/MEAS to enter DO mg/L (or

ppm) calibration mode.

4. To abort calibration, press CAL/MEAS key again to go back to measurement

mode.

While in advanced SETUP mode: Press CAL/MEAS to return to main menu from sub
menus. Press CAL/MEAS again to return to return to measurement mode from main
menu.

2. While in SETUP, pressing the ENTER key confirms selections.

In CALibration & SETUP mode:

In DO mg/L (or ppm) and temperature calibration mode, press up or down keys to
increase or decrease the values.

In SETUP mode, press up or down keys to scroll through the setup subgroup programs.
Within the SETUP sub-menu group, press up or down keys to change values.

defaults, view calibration and electrode data.

LIGHT. Press to activate backlit display.

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Instruction Manual PD 300

3 PREPARATION

3.1 Inserting the Batteries

Four AAA batteries are included with your meter.

1. Use a Philips screwdriver to remove the two screws holding the battery cover. See Figure

3 below.

2. Remove battery cover to expose batteries.

3. Insert batteries. Follow the diagram inside the cover for correct polarity.

4. Replace the battery cover into its original position and secure into place using the two

screws removed earlier.

Figure 3: Back panel of meter showing meter compartment

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Instruction Manual PD 300

3.2 Probe Information

Your meter includes two probes:

• pH electrode with BNC connector.

• DO/temperature probe with a notched 6-pin connector

The temperature sensing element built into the DO probe will also compensate for pH
readings as long as both probes are in your solution at the same time.

You can use any standard pH electrode with a BNC connector with this meter. DO probes, “3-

in-1” pH electrodes with a built-in temperature element, and temperature probes require a

notched 6-pin connector (see Figure 4). For replacement probes, see the Accessories section.

If you want to use a “3-in-1” pH probe with a built-in temperature element, or if you want to use

a separate temperature probe, you will need to disconnect the DO probe to allow for

connection of the separate temperature sensor.

NOTE: Keep connectors dry and clean. Do not touch connector with soiled hands.

To connect the pH electrode:

1. Slide the BNC connector of the probe over the BNC connector socket on the meter.

Make sure the slots of the connector are in line with the posts of the socket. Rotate and

push the connector clockwise until it locks.

2. To remove electrode, push and rotate the connector counterclockwise. While holding

onto the metal part of the connector, pull it away from the meter.

See Figure 4.
CAUTION: Do not pull on the probe cord or the probe wires may be damaged.

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Instruction Manual PD 300

To connect the DO/ temperature probe:

1. Line up the notch and 6 pins on the probe connector with the holes in the connector

located on the top of the meter. Push down and turn the metal locking ring clockwise to

lock the probe connector into place. See Figure 4.

2. To remove probe, unscrew the metal locking ring by turning the ring counterclockwise

and slide up the probe connector. While holding onto metal sleeve, pull probe away from

the meter.

NOTE

Do not substitute other DO probes. For a replacement DO probe, see the “Accessories”
section. Follow the same directions to connect an optional separate temperature element.

CAUTION: Do not pull on the probe cord or the probe wires may be damaged.

Figure 4: Connecting pH and DO/temperature probes

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Instruction Manual PD 300

4 CALIBRATION

4.1 Important Information on Meter Calibration

When you recalibrate your meter, old calibration points are replaced on a “point by point” basis

in pH and completely for % saturation and mg/L (ppm).

For example:

• pH: if you previously calibrated your meter at pH 4.01, 7.00 and 10.01, and you

recalibrate at pH 7.00, the meter retains the old calibration data at pH 4.01 and pH 10.01.

• % saturation and mg/L (ppm): all new calibrations automatically override existing

calibration data.

To view current calibration points:

• pH: Program 1.0 in the SETUP section, page 30.

• % saturation: Program 3.0 in the SETUP section: page 41.

• mg/L (ppm): Program 2.0 in the SETUP section, page 41.

To completely recalibrate your meter, or when you use replacement probes, it is best to clear

old calibration data by resetting the meter.

To reset the meter to its factory defaults:

• pH: Program 4.0 in the SETUP section, page 36.

• % saturation: Program 7.0 in the SETUP section: page 49.

• mg/L (ppm): Program 6.0 in the SETUP section, page 49.

NOTE

Resetting the meter will set meter to factory defaults. pH, % saturation and mg/L (ppm) must
be reset separately.

For directions on how to calibrate your meter:

See section 4.2 for Temperature Calibration

See sections 4.3 for pH calibration.

See section 4.5 for % saturation calibration

See sections 4.6 for mg/L (ppm) calibration

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Instruction Manual PD 300

4.2 Temperature Calibration

The temperature sensor of the the DO probe is factory

calibrated. Calibrate your sensor only if you suspect

temperature errors that may have occurred over a long

period of time or if you have a replacement probe. Make sure

the DO probe is attached prior to performing the calibration.

1. Switch the meter on. Press MODE to select either pH or
mg/L (ppm) measurement mode.

2. Press the CAL/MEAS key to enter pH or mg/L (ppm)
calibration mode. The CAL indicator will appear above the
primary display.

3. While in pH or mg/L (ppm) calibration mode, press the
MODE key to enter temperature calibration mode. The
primary display shows the temperature reading and the
secondary display shows you the factory default
temperature value.

4. Compare the primary display reading to a NIST­traceable thermometer or another thermometer known
to be accurate.

5. Press the ▲ or ▼ keys to adjust the primary display
reading to agree with your temperature standard.

6. Press the ENTER key to confirm temperature calibration
and return to Measurement mode.

NOTE

• To exit from Temperature Calibration mode without

confirming calibration, DO NOT press ENTER in Step 6.
Press CAL/MEAS instead.

• If a separate temperature probe is used for pH

measurement (EC-PHWPTEMP-01W / 35618-05), then
temperature calibration done for pH is separate and
independent from mg/L measurement mode.

• Te mperature calibration is restricted to ± 5°C from the

factory default value displayed during calibration
(shown in the secondary display).

(The values shown above are for illustration purpose. Your meter may display
different values depending on the settings & your environmental conditions)

8

Figure 5: Temperature calibration

Instruction Manual PD 300

4.3 pH calibration

Before starting calibration, make sure you are in pH measurement mode.

NOTE

We recommend calibration with at least two calibration standards that bracket (one
above and one below) the expected sample range. One point calibration is possible as
long as the chosen buffer is close to the expected sample value.

When you re-calibrate your meter, old calibration points are replaced on a “point-by-point”

basis. For example:

• if you previously calibrated your meter at pH 4.01, 7.00, and 10.01, and you re-
calibrate at pH 7.00, the meter retains the old calibration data at pH 4.01 and pH

10.01.

Preparing for pH calibration

This meter is capable of up to 5-point pH calibration to ensure accuracy across the entire pH

range of the meter. Select from the following buffer options:

• pH 1.68, 4.01, 7.00, 10.01 and 12.45.

The meter automatically recognises and calibrates to these standard buffer values, which

makes pH calibration faster and easier.

Be sure to remove the protective electrode storage bottle or rubber ca p of the electrode
before calibration or measurement. If the electrode has been stored dry, hydrate the

electrode in electrode storage solution or tap water for 10 minutes before calibrating or taking

readings to saturate the pH electrode surface and minimise drift.

Rinse your electrode in deionised water after use, and store in electrode storage solution. If

storage solution is not available, use fresh pH 4.01 or 7.00 buffer solution for short term

storage.

Do not reuse buffer solutions after calibration. Contaminants in the solution can affect the

calibration and eventually the accuracy of the measurements. See Accessories for information

on pH buffer solutions.

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Instruction Manual PD 300

To Calibrate pH:

1. If necessary, press the MODE key to select

pH mode. The pH indicator appears in the

upper right hand corner of the display.

2. Rinse the probe thoroughly with de-ionised

water or a rinse solution. Do not wipe the

probe; this causes a build-up of electrostatic

charge on the glass surface.

3. Dip the probe into the calibration buffer. The

end of the probe must be completely

immersed into the sample. Stir the probe

gently to create a homogeneous sample.

NOTE

The temperature element is in the DO electrode. For
temperature compensated readings, dip the DO
electrode into the calibration buffer as well.

4. Press CAL/MEAS to enter pH calibration

mode. The CAL indicator will be shown. The

primary display will show the measured

reading while the smaller secondary display

will indicate the pH standard buffer solution.

5. Wait for the measured pH value to stabilise.

See Figure 5.

6. Press ENTER to confirm calibration. The

meter is now calibrated to the current buffer.

The lower display scrolls through the

remaining buffer options.

• For multi-point calibration, go to step 7.

• For one-point calibration, go to step 9.

10

Figure 6: pH Calibration

Instruction Manual PD 300

7. Rinse the electrode with deionised water or in

rinse solution, and place it in the next pH buffer.

8. Follow steps 5 to 8 for additional calibration

points. See Figure 7.

9. When calibration is complete, press

CAL/MEAS to return to pH measurement mode.

NOTE

To exit from pH calibration mode without confirming
calibration, DO NOT press ENTER in step 6. Press
CAL/MEAS instead.

If the selected buffer value is not within ±1.0 pH from the

measured pH value: the electrode and buffer icon blink

and the ERR annunciator appears in the lower left

Figure 7: Next point calibration for

pH 4.01

corner of the display. See Figure 8.

To limit the number of pH buffer values available during

calibration, see Setup Section 8.4

P3.2: Selecting

number of pH calibration points on page 34.

Figure 8: Err message and

electrode icon will appear if

incorrect buffer is used

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Instruction Manual PD 300

4.4 Dissolved Oxygen Calibration

Before calibrating your meter, make sure to rinse the probe well with de-ionised water or rinse

solution.

NOTE

Do not let membrane surface of the probe touch any
other surface. The probe guard (the piece with holes
fitted over the end of the probe) protects the membrane;
make sure this is always attached to the probe while it
is in use. See Figure 9.

You can calibrate for dissolved oxygen in either %
saturation or mg/L (ppm). All new calibrations

automatically override existing DO calibration data.

Figure 9: DO Probe guard

Before Calibration

Before starting calibration, make sure you are in the correct measurement mode. When you

switch on the meter, the meter starts up in the units last used (either pH, mg/L (ppm) or % air

saturation). For example, if you shut off the meter in “mg/L” units, the meter will read “mg/L”

units when you switch the meter on.

NOTE

Most users will calibrate to 100% saturation even when working in mg/L. When calibrating the
meter in mg/L mode, you can make fine adjustments, typically to a mid-range value between
10 and 100%. If you are calibrating to a mid-range value, you need to set the 100% saturation
value first.

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Instruction Manual PD 300

4.5 Dissolved Oxygen Calibration in % Saturation

You can calibrate this meter quickly and easily in air. The exact calibration value depends on

barometric pressure. The meter is set to a factory default of 760 mm Hg, which results in a

calibration value of 100% saturation in air.

NOTE

If the barometric pressure setting has been changed from 760 mm Hg, the calibration value in
air will automatically adjust to a value other than 100%. The adjusted value will be correct for
the new barometric pressure setting.

See Section 8.6.1 on page 37 to change the pressure setting. See Addendum 2 on page 67

for a table of adjusted % saturation values.

To calibrate 100% Saturation:

1. Rinse the probe well with deionised rinse water. Do not touch

the membrane.

2. Press the MODE key to select the % saturation mode.

3. Press the CAL key. The CAL indicator will appear above the

primary display. The primary display shows the current value

of the measurement and the secondary display will show

100.0. See figure on right and NOTE above.

4. Hold the probe in the air. Wait for the reading to stabilise. If

the READY indicator feature is enabled, it will appear when

the reading is stable. (See page 45 for Ready indicator

setup.)

5. Press the ENTER key. The meter automatically calibrates to

100.0% air saturation and returns to Measurement mode.

NOTE

Whenever an error occurs during calibration, the ERR indicator
appears in the lower left hand corner of the display.

You can offset your % DO calibration. See page 40 for directions.

13

Figure 10: To calibrate for

100% saturation

Instruction Manual PD 300

To calibrate 0% Saturation:

1. Rinse the probe well with deionised rinse water. Do not

touch the membrane.

2. Press the MODE key to select the % saturation mode.

3. Place the probe in zero oxygen solution. Stir the probe

gently to homogenise the sample. Make sure that the

READY

MEAS

128 . 5

L

A

C

S

A

E

M

23.4

%

°C
ATC

sample is continuously flowing past the membrane sensor.

4. Press the CAL key. The CAL indicator will appear above

CAL

%

the primary display. The primary display shows the current

value of the measurement and the secondary display will

show 0.0.

5. Wait for the reading to stabilise. If the READY indicator

R

E

T

N

E

feature is enabled, it will appear when the reading is stable.

(See page 45 for Ready indicator setup.)

READY

MEAS

%

6. Press the ENTER key. The meter automatically calibrates

to 0.0% air saturation and returns to Measurement mode.

23.4

°C
ATC

See figure on right.

NOTE

Figure 11: To calibrate for

0% saturation

The reading in the primary display in step 3 must read at 10% or
under for the calibration to work correctly. Whenever an error occurs during calibration, the
ERR indicator appears in the lower left hand corner of the display.

You can offset your % DO Calibration; see page 40 for directions.

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Instruction Manual PD 300

4.6 Dissolved Oxygen Calibration in mg/L (ppm) mode

Calibrating the meter to 100% in saturation mode will also calibrate the mg/L mode at the

value in mg/L corresponding to 100% saturation. This should produce acceptable results in

most applications.

This meter also lets you make a calibration adjustment in mg/L (ppm) mode without affecting

your % saturation calibration. To select between mg/L and ppm units, see page 46.

NOTES ON MG/L (PPM) MODE CALIBRATION

• During mg/L (ppm) measurement and calibration, the meter adjusts to the

barometric pressure value that is programmed into the meter. It also adjusts to

the salinity value that is programmed into the meter.

• You can change the barometric pressure value and salinity value in the mg/L

(ppm) SETUP mode (see Section 8.6 -- P1.0 (dPr): Dissolved Oxygen

Parameters) for directions).

• Whenever an error occurs during calibration, the ERR indicator appears in the

lower left hand corner of the display.

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Instruction Manual PD 300

To calibrate in mg/L (ppm) mode:

1. Calibrate 100% saturation as per Section 4.5.

2. Rinses the probe well with deionised rinse water. Wipe

the outside of the probe carefully (do not touch the

membrane).

3. Dip the probe into a sample of known oxygen

concentration. Wait for the reading to stabilise. If the

READY indicator feature is enabled, it will appear when

the reading is stable.

4. Press the MODE key to select the mg/L (ppm) mode.

5. Press the CAL key. The CAL indicator will appear above

the primary display. The primary display shows the

current value of the measurement and the secondary

display shows the temperature.

6. Press the ▲ and ▼ keys to adjust the reading.

7. Press the ENTER key. The meter automatically

calibrates to the value you entered and returns to

Measurement mode.

Figure 12: To calibrate in

mg/L (ppm) mode

(The values shown above

are for illustration purpose.

Your meter may display

different values depending

on the settings & your

environmental conditions)

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Instruction Manual PD 300

5 MEASUREMENT

5.1 Taking pH Measurements

5.1.1

Automatic Temperature Compensation only occurs when a compatible temperature sensing

element is plugged into the meter.
If there is no temperature sensor plugged into the meter, the default manual temperature

setting is 25 °C. You can manually set the temperature to match your working conditions

using a separate thermometer.

For automatic temperature compensation (ATC) simply

plug the temperature probe into the meter (see page 6

for directions). The ATC indicator will light up on the

LCD. See figure on right.

NOTE

The temperature sensing element must be in the
sample that you are calibrating or measuring.

Automatic Temperature Compensation

Figure 13: Automatic Temperature

Compensation

5.1.2

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Instruction Manual PD 300

Manual Temperature Compensation (pH only)

IMPORTANT: For manual compensation, you must

disconnect the temperature probe (see page 10).

1. Switch the meter on. Press the MODE key to

select pH mode.

2. Press the CAL/MEAS key to enter pH

calibration mode. The CAL indicator will

appear above the primary display.

3. While in pH calibration mode, press the
MODE key to enter temperature calibration

mode. The primary display shows the

current temperature setting and the

secondary display shows the default value

25 °C.

4. Check the temperature of your sample using

an accurate thermometer.

5. Press the ▲ or ▼ keys to set the

temperature to the measured value from step

4.

6. Press ENTER to confirm the selected

temperature and to return to the pH

measurement mode.

See Figure 14.

The meter will now compensate pH readings for the

manually set temperature.

Figure 14: Manual temperature

compensation

NOTE

To exit this program without confirming the manual temperature compensation value,
DO NOT press ENTER in step 6. Press CAL/MEAS instead.

5.1.3

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Instruction Manual PD 300

Taking Measurements (pH)

Be sure to remove the electrode storage bottle or

protective rubber cap on the electrode before taking

measurements. To ensure Automatic Temperature

Compensation (ATC) for pH measurements, the DO

or ATC probe must be plugged in and immersed into

the sample.

To take readings:

1. Rinse the pH electrode with deionised or distilled water before use to remove any

impurities adhering to the probe body. If the pH electrode has dehydrated, soak it

for 30 minutes in electrode storage solution (sold separately).

2. Press ON to switch on meter.

3. Press the MODE key to select pH measurement mode. The MEAS annunciator

appears on the top center of the LCD. The ATC indicator appears in the lower right-

hand corner to indicator Automatic Temperature Compensation.

NOTE

For pH manual temperature compensation, you must disconnect the DO electrode from
the 6-pin connector. The ATC indicator will disappear from the display. You also need to
set a manual temperature compensation value. See Section 5.1.2 on page 18 to set
Manual Temperature Compensation.

Figure 15: Measurement mode

4. Dip the probe into the sample. Since the DO electrode contains the temperature

sensor, make sure it is also immersed in your solution.

When dipping the probe into the sample, the sensor or the glass bulb of the electrode
must be completely immersed into the sample. Stir the probe gently in the sample to
create a homogeneous sample.

5. Allow time for the reading to stabilise. Note the reading on the display. If the Ready

indicator is selected on, it will appear when the reading is stable. See below for

more information.

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Instruction Manual PD 300

Taking measurements with READY indicator selected on

If the READY indicator has been activated, the READY annunciator lights when the reading is

stable*. Switch the READY indicator on or off in SETUP Section 8.4 Program P3.1.

* The READY indicator appears and the reading holds until the measured value

exceeds the tolerance. Then, the READY annunciator turns off.

Taking measurements with the auto endpoint feature selected on

When a reading is stable for more than 5 seconds, the auto endpoint feature will automatically

“HOLD” the reading. The “HOLD” indicator appears on the left side of the display. Press the

HOLD key to release the reading. Switch the Auto endpoint feature on or off in SETUP

Section 8.4 Program P 3.1.

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Instruction Manual PD 300

5.2 Taking DO read in gs

During measurement, the probe can be:

z Fully immersed in the solution

z Partially immersed in the solution

Do not allow the probe’s membrane surface to touch

anything! The probe guard (the piece with holes fitted

over the end of the probe) protects the membrane; you

should leave this piece attached to the probe at all

times.
IMPORTANT: Since the DO probe consumes oxygen

from the sample, the sample must constantly flow past

the membrane to achieve more accurate readings. You

can use a stirrer to accomplish this.

To take measurements:

1. Rinse the probe well with deionised rinse water or

rinse solution.

2. Select the appropriate measurement mode. Press the

MODE key to toggle between modes:

z % Saturation

z mg/L (ppm) **

z pH

3. Dip the probe into the sample. Stir the probe gently to

homogenise the sample. Make sure that the sample is

continuously flowing past the membrane sensor.

Figure 16: Change

measurement mode from %

saturation to mg/L

4. Note the reading on the display. If the READY

indicator is switched on, it will appear when the

reading is stable.

Figure 17: Taking

measurement

5. Press the “LIGHT” key to activate the backlit LCD. This

helps you read measurements in dimly lit areas.

** To select between mg/L and ppm units, see Section 8.10.2 on page 46.

The ATC indicator should appear in the lower right hand corner of the display. If it does not,

this indicates an error.

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Instruction Manual PD 300

Taking measurements with READY ON indicator selected on

If the READY indicator has been activated, the READY annunciator lights when the reading is

stable.

To switch the READY indicator on or off in the SETUP program – see Section 8.10.1 on page

45 for directions.

Taking measurements with READY HOLD indicator selected on

When a reading is stable for more than 5 seconds, the

auto endpoint feature will automatically “HOLD” the

reading. The “HOLD” indicator appears on the left side of

the display. Press the HOLD key to release the reading.

To switch the Auto endpoint feature on or off in the

SETUP program – see Section 8.10.1 on page 45 for

directions.

(The values shown here are for illustration purpose. Y our meter may display
different values depending on the settings & your environmental conditions)

Figure 18 – Auto endpoint

feature

22

Instruction Manual PD 300

5.3 Taking Pressure/Salinity Compensated DO measurements

If necessary, you can adjust the pressure and salinity values of your measurements in the

SETUP mode. The DO meter will automatically compensate for salinity and pressure based on

the values entered in the SETUP functions. The meter is factory set at 760 mm Hg (101.3

Pascals) pressure adjustment and a factor of 0.0 ppt salinity adjustment. See Addendum 2 on

page 67 for a “Pressure vs Altitude” table.

Pressure Adjustment

NOTE

This mode appears in both the % saturation and mg/L (ppm) measurement modes.

1. While in the measurement mode, press “Mode” key if necessary to enter DO
measurement mode.

2. Press the SETUP key to enter SETUP mode.

3. The upper display shows “dPr”.

4. Press the ENTER key until the upper display shows a number and the lower display
shows “Hg” or “PA”.

5. Use the ▲ or ▼keys to enter the barometric pressure. The upper display will show the
value you have entered.

6. Press ENTER to confirm pressure value.

7. Press CAL/MEAS to return to Measurement mode, or continue with step 4 on page 39 to
make a salinity adjustment [available in mg/L (ppm) mode only].

8. See section 8.6.1 - “P1.1 Pressure adjustment mode” on page 37.

Salinity Adjustment

NOTE

This mode appears in ppm (mg/L) measurement mode only.

1. Press the MODE key to select mg/L (ppm) mode.

2. Press the SETUP key to enter SETUP mode.

3. The upper display shows “dPr”.

4. Press the ENTER key until the upper display shows a number and the lower display
shows “SAL”.

5. Use the ▲ or ▼ keys to enter the salinity of your solution in parts per thousand. Note
1000 ppm = 1 ppt. The upper display will show the value you have entered.

6. Press ENTER key to confirm value.

7. Press CAL/MEAS to return to Measurement mode.

8. See section 8.6.2 - P1.2: Salinity Adjustment Mode on page 39.

23

Instruction Manual PD 300

6 HOLD FUNCTION

This feature lets you freeze the pH, dissolved oxygen,

and temperature readings for a delayed observation.

HOLD can be used any time when in MEAS mode.

To hold a measurement, press the HOLD key while in

measurement mode. “HOLD” will appear on the

display.

To release the held value, press HOLD again.

Continue to take measurements.

NOTE

The meter shuts off automatically 20 minutes after the
last key press. If the meter is shut off either
automatically or manually, the HOLD value will be lost.

NOTE

This meter has an auto endpoint feature. When this
feature is switched on, the display will automatically
“HOLD” a reading that has been stable for more than
5 seconds. The “HOLD” indicator appears. Press the
HOLD key to release the reading. To switch on or off
the auto endpoint feature, see page 45.

Figure 19: HOLD feature

(The values shown are for illustration purpose. Your meter may display differen t values depending on the settings & your
environmental conditions)

24

Instruction Manual PD 300

7 BACKLIT LCD

7.1 Using the backlit LCD

This feature lets you view readings in low light situations.

1. To activate the backlit LCD feature, press the

key to activate.

To conserve batteries, the backlight automatically shuts off after 20 seconds. To keep the LCD

backlit, keep the backlight key pressed.

7.2 Adjusting the LCD brightness

This mode lets you adjust the brightness of the backlit

LCD. Selecting a dimmer backlighting level helps

conserve batteries. This adjustment is only available in

the % saturation or mg/L (ppm) SETUP modes.

From the measurement mode:

1. Press the MODE key to switch to % saturation or

mg/L (ppm) mode.

2. Press SETUP key to enter setup mode.

3. Press the ▲ or ▼ keys to scroll through subgroups

until you view parameters “LCd” in the upper display.

4. Press the ENTER key. A number (0-8) appears in

the upper display and “LCd” appears in the lower

display.

5. Press the ▲ or ▼ keys to select from level 0

(dimmest light) to level 8 (brightest light).

6. Press the ENTER key to confirm selection and to

return to the subgroup menu. Press the CAL/MEAS

key to return to measurement mode.

25

Figure 20: Adjusting LCD

Brightness

Instruction Manual PD 300

8 ADVANCED SETUP FUNCTIONS

The advanced SETUP mode lets you customise your meter’s preferences and defaults. Your

waterproof meter features different sub groups that organise all set-up parameters.

Each measurement parameter (pH, % saturation, & mg/L) has its own sets of customisable

setup functions. Some of which are unique and independent while others are common for the

whole meter.

The full selection of available sub groups is shown in the following three pages.

8.1 Advanced SETUP Mode Detailed Overview

1. In either pH or DO measurement mode, press the SETUP key to enter Set up mode.

2. Press the ▲ or ▼ keys to scroll through sub groups.

3. Press ENTER key to enter a particular parameter.

See Addendum 3 on page 68 for a table of meter factory default settings.

26

Instruction Manual PD 300

SETUP in pH Measurement Mode

P1.0: View previous calibration data

P1.1 First calibration point (pH 1.68)
P1.2 Second calibration point (pH 4.01)
P1.3 Third calibration point (pH 7.00)
P1.4 Fourth calibration point (pH 10.01)
P1.5 Fifth calibration point (pH 12.45)

Instructions on page 30.

P2.0: View electrode data

P2.1 pH electrode offset
P2.2 pH electrode slope

Instructions on page 31.

P3.0: Unit configuration

P3.1 READY indicator and auto endpoint function –

P3.2 Number of pH calibration points: 2, 3, 4 or 5
P3.3 Select °C or °F

Instructions begin on page 32.

select on or off

P4.0: Reset to factory defaults

P4.0 Reset meter to factory defaults

Instructions on page 36.

27

Instruction Manual PD 300

% Saturation Measurement Mode

dPr: Dissolved Oxygen parameters

• Select Hg or Pa barometeric pressure units

• Select barometric pressure

Instructions on page 37.

OFS: % saturation offset adjustment

• Set % saturation offset adjustment

Instructions on page 40.

CAL: Viewing previous calibration data

• View previous calibration data

Instructions on page 41.

ELE: Viewing probe data

• View probe slope

• View % saturation offset value

• View mV value equivalent to 100% saturation

• View mV value equivalent to 0% saturation

Instructions begin on page 42.

COF: Unit configuration

• Ready indicator ON or OFF / auto endpoint ON
or OFF

• Select °C or °F

Instructions begin on page 44.

LCd: Backlit display

• Adjust brightness of backlit LCD

Instructions on page 48.

rSt: Reset to factory default

• Reset to factory default settings

Instructions on page 49.

28

Instruction Manual PD 300

mg/L (ppm) Measurement Mode

dPr: Dissolved Oxygen parameters

• Select Hg or Pa barometric pressure units

• Select barometric pressure

• Select salinity adjustment factor

Instructions on page 37.

CAL: Viewing previous calibration data

• View previous calibration data

Instructions on page 41.

ELE: Viewing probe data

• View probe slope

• View mV value equivalent to 100% saturation

• View mV value equivalent to 0% saturation

Instructions begin on page 42.

COF: Unit configuration

• Ready indicator ON or OFF / auto endpoint ON
or OFF

• Select mg/L or ppm units

• Select °C or °F

Instructions begin on page 44.

LCd: Backlit display

• Adjust brightness of backlit LCD

Instructions on page 48.

rSt: Reset to factory default

• Reset to factory default settings

Instructions on page 49.

29

Instruction Manual PD 300

8.2 P1.0: Viewing previous pH calibration data

This mode lets you recall previous pH calibration data,

which helps you know when to re-calibrate your meter.

This is a “view only” mode.

From measurement mode:

1. Press the MODE key to select pH measurement

mode if necessary.

2. Press the SETUP key to enter Set up mode.

3. Press the ▲ or ▼ keys to scroll through

subgroups until you view parameter P1.0.

4. Press the ENTER key repeatedly to view previous

calibration data. See figure on right.

• P1.1 = pH 1.68

• P1.2 = pH 4.01

• P1.3 = pH 7.00

• P1.4 = pH 10.01

• P1.5 = pH 12.45

5. When you have scrolled through all calibration

data, you will automatically return to the subgroup

menu. Press CAL/MEAS key to return to

measurement mode.

NOTE

If there is no previous calibration data at a particular
point, the primary display will show “ ----“.

30

Figure 21 – P1.0: View calibration

data for pH

Instruction Manual PD 300

8.3 P2.0: Viewing pH electrode data

Program 2 has two “view only” options that let you

check the electrode parameters for diagnostic

purposes. It lets you view:

• P2.1 = Electrode offset

• P2.2 = Electrode slope

From pH measurement mode

1. Press the MODE key to select pH measurement

mode.

2. Press the SETUP key to enter Set Up mode.

3. Press the ▲ or ▼ keys to scroll through

subgroups until you view parameter P2.0.

4. Press the ENTER key to select parameter 2.1.

5. The display shows the electrode offset value. It is

the mV offset at pH 7.00. If you have not

calibrated at any buffer, the primary display shows

0.00 mV.

6. Press the ENTER key to proceed to P2.2.

7. The display shows electrode slope in percentage.

Slope displayed is the average slope based on the

pH calibrations. Default setting is 100.0.

8. At any point, you can press the CAL/MEAS key to

return to measurement mode.

See figure on right.

31

Figure 22: Viewing electrode's

offset and slope status from pH

measurement mode

(The values shown above are for

illustration purpose. Your meter may

display different values depending

on the settings & your

environmental conditions)

Instruction Manual PD 300

8.4 P3.0: pH Measurement co nfiguration

This subgroup program allows to customise the meter

to your specific needs. You can program the meter to:

1. Select READY indicator ON or OFF

2. Select the number of pH calibration points

3. Select between °C and °F units for temperature

readings

Figure on the right shows the setup sequence for this

program subgroup.

Figure 23 – P 3.0: Unit

configuration program

32

Instruction Manual PD 300

P3.1: READY Indicator and auto endpoint function

This program lets you select:

• “

READY indicator on” to indicate when the

reading is stable.

• “

READY indicator off” for faster meter response.

•

Auto endpoint function on. Select auto endpoint
on to “hold” the reading when it is stable for more
than 5 seconds. The display automatically freezes,
and the HOLD indicator appears on the left side of
the display. Press the HOLD key to release the
display and access other functions.

From measurement mode

1. Press the MODE key to select pH measurement

mode.

2. Press SETUP key to enter Set Up mode.

3. Press the ▲ or ▼ keys to scroll through subgroups

until you view parameter P3.0.

4. Press the ENTER key to select parameter 3.1.

5. Press the ▲ or ▼ keys to select the configuration

you require.

• OFF switches the READY indicator off.

• ON switches the READY indicator on.

• ON and HOLD together switches the auto

endpoint feature on.

6. Press the ENTER key to confirm selection and to

proceed to step 4 of P3.2. Press the CAL/MEAS key

to return to measurement mode.

Figure 24 – P 3.1: Selecting

READY function)

NOTE

Meter default is set for READY indicator on and auto endpoint function off.

You can also change the Ready indicator and auto endpoint function in the DO mode. Any

changes you make to the Ready indicator/auto endpoint function in pH mode will also change

in DO mode.

33

Instruction Manual PD 300

P3.2: Selecting number of pH calibration points

Program P3.2 lets you select the number of calibration

points that appear in pH calibration mode: 2, 3, 4, or 5.

The meter will automatically exit calibration mode after

you have calibrated to your selected number of points.

From measurement mode.

1. Press the MODE key to select pH measurement

mode.

2. Press SETUP key to enter Set Up mode.

3. Press the ▲ or ▼ keys to scroll through subgroups

until you view parameter P3.0.

4. Press the ENTER key twice to select parameter 3.2.

5. Press the ▲ or ▼ keys to select 2, 3, 4, or 5 point

pH calibration.

6. Press the ENTER key to confirm selection and to

return to the subgroup menu. Press CAL/MEAS

key to return to measurement mode.

See Figure on right.

Figure 25 – P3.2: Select number

of pH calibration points

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Instruction Manual PD 300

P3.3 Selecting °C or °F

This meter lets you select between °C and °F units for

temperature readings.

From measurement mode

1. Press the MODE key to select pH measurement

mode.

2. Press SETUP key to enter Set Up mode.

3. Press the ▲ or ▼ keys to scroll through

subgroups until you view parameter P3.0.

4. Press the ENTER key three times to select

parameter 3.3.

5. Press the ▲ or ▼ keys to toggle between °C and

°F.

6. Press the ENTER key to confirm selection and to

return to the subgroup menu. Press the

CAL/MEAS key to return to measurement mode.

Figure 26 – P3.3: Select

temperature units

See Figure on right.

NOTE

You can switch between °C and °F in Program P5.2 of % saturation mode (or P4.3 in mg/L
mode). If you switch between °C and °F in pH mode, the meter will also switch in % saturation
or mg/L mode.

35

Instruction Manual PD 300

8.5 P4.0: Resetting to factory default settings (pH)

This program lets you reset all pH parameters to factory default settings. This clears all

calibration data and any other pH setup functions you might have changed.

The following settings will remain as you have set them:

• Temperature unit of measure (°C or °F)

• The temperature offset calibration value

• All DO calibration data and parameters

There are also some other parameters that retain settings when reset is done. See Addendum

3 on page 68 for a table of factory default settings.

From measurement mode

1. Press the MODE key to select pH measurement mode.

2. Press SETUP key to enter Set Up mode.

3. Press the ▲ or ▼ keys to scroll through subgroups until

you view parameter P4.0 in the lower display.

4. Press the ENTER key to enter parameter P4.0.

5. Press the ▲ or ▼ keys to toggle between NO and YES.

See figure on right.

• NO retains current settings

• YES resets to factory default settings.

6. Press the ENTER key to confirm selection and to return

to the measurement mode. Otherwise press CAL/MEAS

key to return to measurement mode without resetting to

factory default.

Figure 27 – P4.0: Reset to factory

default values

NOTE

See page 68 for a table of factory default settings.

36

Instruction Manual PD 300

8.6 P1.0 (dPr): Dissolved Oxygen Parameters

This sub group is available in % saturation and mg/L (ppm) mode and lets you adjust the

barometric pressure and salinity (% saturation mode only).

8.6.1 P1.1 Pressure adjustment mode

Barometric pressure is vital to correct dissolved oxygen measurements. You need to enter the

correct barometric pressure of the area you are measuring. This mode lets you perform two

functions:

• Select either mm Hg or Pascal barometric pressure units.

• Adjust the barometric pressure. See Addendum 2 on page 67 for a

“Pressure vs Altitude” table.

From measurement mode:

1. Press the MODE key to select DO measurement mode.

2. Press the SETUP key to enter SETUP mode.

3. Press the ▲ or ▼ keys to scroll through subgroups until you view parameter “dPr” in the

upper display.

4. Press the ENTER key twice. The upper display shows either Hg or PA and the lower

display shows bAr. See figure on next page.

5. Press the ▲ or ▼ keys to toggle between mm Hg and Pascal units.

6. Press the ENTER key to confirm selection and move to the next screen. The upper

display shows the barometric pressure and the lower display shows the units selected in

Step 3.

7. Press the ▲ or ▼ keys to adjust the barometric pressure. The pressure adjustment

range is 500 to 1499 mm Hg (66.6 to 199.9 kPa).

8. Press the ENTER key to confirm selection and move to Step 4 on page 39 [salinity
adjustment appears in mg/L (ppm) measurement mode only]. If instead you want to

return to measurement mode, press CAL/MEAS twice.

37

Instruction Manual PD 300

8.6.2

Figure 28: Change pressure units (mm Hg or kPa) & adjusting its values

38

Instruction Manual PD 300

P1.2: Salinity Adjustment Mode

NOTE

This mode appears in mg/L (ppm) measurement mode
only.

Salinity correction mode lets you correct for the

variations in oxygen solubility due to salt concentration

in the sample.

From measurement mode:

1. Press the MODE key to select mg/L (ppm) mode.

2. Press the SETUP key to enter SETUP mode.

3. Press ▲ or ▼ keys to scroll through subgroups

until you view parameter “dPr” in the upper display.

4. Press the ENTER key five times. The upper

display shows the salinity value and the lower
shows SAL.

5. Press ▲ or ▼keys to enter the correct salinity

adjustment factor. The salinity adjustment factor

range is 0.0 to 50.0 ppt.

6. Press the ENTER key to confirm selection and to

move back to subgroup “dPr”. If you want to return

to measurement mode, press CAL/MEAS.

39

Figure 29: Input Salinity values for
automatic correction

(The values shown above are for
illustration purpose only)

Instruction Manual PD 300

8.7 P2.0 (OFS): Offset for % Saturation

Measurement

NOTE

This sub group appears in % saturation measurement
mode only.

From measurement mode:

1. Press the MODE key to select % saturation mode.

2. Press the SETUP key to enter SETUP mode.

3. Press ▲ or ▼ keys to scroll through subgroups

until you view parameter “OFS” in the upper

display.

4. Press the ENTER key. The upper display shows

the current measurement in % saturation and the

lower shows “OFS”.

5. Press ▲ or ▼ keys to offset the % saturation

measurement.

6. Press the ENTER key to confirm selection and to

move back to subgroup “OFS”. If you want to

return to measurement mode, press CAL/MEAS.

(The values shown above are for illustration purpose. Your meter may
display different values depending on the settings & your environmental
conditions)

40

Figure 30: Offset for % saturation

Instruction Manual PD 300

8.8 P3.0 [P2.0] (CAL): Previous Calibration Information

(*Program numbers in “[ ]” are for setup in mg/L (ppm) mode.

This sub group shows you the previous calibration data. This is a “view only” parameter.

In % saturation mode: Calibration information is shown in % saturation units.

In mg/L (ppm) mode: Calibration information is shown in mg/L (ppm) units.

From measurement mode:

1. Press the MODE key to select the calibration data

you want to view: % or mg/L (ppm).

2. Press the SETUP key to enter SETUP mode.

3. Press ▲ or ▼ keys to scroll through subgroups

until you view parameter “CAL” in the upper display.

4. Press the ENTER key. The upper display shows the

calibration data.

5. Press the ENTER key to move back to subgroup

“CAL”. If you want to return to measurement mode,

press CAL/MEAS.

NOTE: If you did not calibrate this meter in a particular

mode, the screen will show “ ---“. See Figure 30.

(The values shown above are for illustration purpose. Your meter may
display different values depending on the settings & your environmental
conditions)

41

Figure 31: View calibration data

Figure 32: eter is not calibrated

Instruction Manual PD 300

8.9 P4.0 [P3.0] (ELE): Electrode Properties

These “view only” parameters show you the electrode

properties for diagnostic purposes:
A. P4.1 [P3.1] Probe Slope: Provides an indication of the

probe’s efficiency. The value displayed is the ratio of the

theoretical value to the actual value produced by the

probe. The higher the number, the lesser output from the

probe. The ratio displays from 0.5 to 1.999% (1.0 = 100%).

P4.2 % Saturation Offset: (available in % saturation

B.

mode only): Shows the value of the % saturation offset

entered in parameter “OFS” (see page 40 for instructions).
P4.3 [P3.2] 100% Saturation mV value: Lets you view

C.

the sensor’s mV output corresponding to 100% saturation.
P4.4 [P3.3] 0% Saturation mV Value: Lets you view the

D.

sensor’s millivolt output corresponding to 0% saturation.

From measurement mode:

1. Press the MODE key to select the measurement mode for

the electrode properties you want to view: % or mg/L

(ppm).

2. Press the SETUP key to enter SETUP mode.

3. Press ▲ or ▼ keys to scroll through subgroups until you

view parameter “ELE” in the upper display.

4. Press the ENTER key. The upper display shows the probe

slope.

5. Press the ENTER key. The upper display shows the %

saturation offset. See directions for setting this offset on

page 40. NOTE: This appears only in % saturation

measurement mode. If you are in mg/L (ppm) mode, the

meter skips to step 6 on page 43.

42

Figure 33: iew electrode

properties from %

saturation

Instruction Manual PD 300

6. Press the ENTER key. The upper display shows the

100% saturation mV value.

7. Press the ENTER key. The upper display shows the 0%

saturation mV value.

8. Press the ENTER key to move back to subgroup “ELE”.

If you want to return to measurement mode, press

CAL/MEAS.

(The values shown above are for illustration purpose. Your meter may display
different values depending on the settings & your environmental conditions)

Figure 34: View electrode

properties from mg/L

(ppm) mode

43

Instruction Manual PD 300

8.10 P5.0 [P4.0] COF: Unit Configuration

Unit configuration mode lets you select the following parameters:

A. P5.1 [P4.1] READY indicator and auto endpoint function.

B. [P4.2] mg/L or ppm units (available in mg/L or ppm mode only)

C. P5.2 [P4.3] Temperature in °C or °F.

8.10.1

Figure 35: Unit configuration

from % saturation

measurement mode

Figure 36: Unit configuration

from mg/L measurement mode

44

Instruction Manual PD 300

P5.1 [P4.1] READY Indicator and Auto Endpoint Function

The first program lets you select:

•

“READY indicator ON” to indicate when the

reading is stable.

• “READY indicator OFF” for faster meter response.

•

Auto Endpoint Function ON. Select auto endpoint

ON to “HOLD” the reading when it is stable for more

than 5 seconds. The display automatically freezes,

and the HOLD indicator appears on the left side of

the display. Press the HOLD key to release the

display and access other functions.

From measurement mode

1. Press SETUP key to enter SETUP mode.

2. Press ▲ or ▼ keys to scroll through subgroups until

you view parameter COF in the upper display.

3. Press the ENTER key to select parameter “rdY”

(Ready).

4. Press ▲ or ▼ keys to select the configuration you

require.

• ON switches the READY indicator on.

• OFF switches the READY indicator off.

• ON and HOLD together switches the auto

endpoint feature on.

5. Press the ENTER key to confirm selection and to

proceed to:

• In % mode: step 4 on page 47.

• In mg/L (ppm) mode: step 5 on page 46.

Or press the CAL/MEAS key twice to return to

Figure 37: To configure for
READY and Auto Endpoint

functions

measurement mode.

Note: Meter default is set for Ready indicator ON, and auto endpoint function off. Any

changes made to the Ready indicator/auto endpoint function will change in the pH
mode as well.

45

Instruction Manual PD 300

8.10.2 [P4.2] Selecting mg/L or ppm units

NOTE

This mode appears in mg/L (ppm) measurement mode only.
This mode lets you select between mg/L or ppm dissolved oxygen units.

From measurement mode

1. Press the MODE key to select mg/L (ppm) mode.

2. Press SETUP key to enter SETUP mode.

3. Press ▲ or ▼ keys to scroll through subgroups

until you view parameter “COF” in the upper

display.

4. Press the ENTER key until “dO” appears in the

upper display.

5. Press ▲ or ▼ keys to toggle between mg/L or

ppm units.

6. Press the ENTER key to confirm selection. Press

the CAL/MEAS key twice to return to

measurement mode.

Figure 38: Change from mg/L to

ppm unit

46

Instruction Manual PD 300

8.10.3 P5.2 [P4.3] Selecting °C or °F Temperatu re Unit

This meter lets you select between °C and °F units for temperature readings.

From measurement mode

1. Press SETUP key to enter SETUP mode.

2. Press ▲ or ▼ keys to scroll through subgroups

until you view parameter “COF” in the upper

display.

3. Press the ENTER key until “C” or “F” appears in

the upper display.

4. Press ▲ or ▼ keys to toggle between °C and °F.

5. Press the ENTER key to confirm selection and to

return to the subgroup menu. Press the

CAL/MEAS key to return to measurement mode.

Note: Any changes made to the temperature unit
selection will change in the pH mode as well.

47

Figure 39: To change from units of

measurement for temperature

Instruction Manual PD 300

8.11 P6.0 [P5.0] LCd: Adjusting LCD Brightness

NOTE

This function is only available through DO measurement mode (% saturation or mg/L)

This mode lets you adjust the brightness of the backlit LCD. Selecting a dimmer back-lighting

level helps conserve batteries.

From measurement mode

1. Press SETUP key to enter SETUP mode.

2. Press ▲ or ▼ keys to scroll through subgroups

until you view parameter “LCd” in the upper

display.

3. Press the ENTER key. A number (0 – 8) appears

in the upper display and “LCd” appears in the

lower display.

4. Press ▲ or ▼ keys to select from level 0

(dimmest light) to level 8 (brightest light).

5. Press the ENTER key to confirm selection and to

return to the subgroup menu. Press the

CAL/MEAS key to return to measurement mode.

Figure 40: Adjusting LCD

brightness

48

Instruction Manual PD 300

8.12 P7.0 [6.0] rSt: Resetting to Factory Default Setting (DO)

This program lets you reset all DO (% saturation and mg/L) parameters to factory default

settings. This clears all calibration data and any other DO setup functions you might have

changed.

The following settings will remain as you have set them:

• Temperature unit of measure (°C or °F)

• The temperature offset calibration value

• All DO calibration data and parameters

There are also some other parameters that retain settings when reset is done. See Addendum

3 on page 68 for a table of factory default settings.

From measurement mode

1. Press SETUP key to enter SETUP mode.

2. Press ▲ or ▼ keys to scroll through subgroups

until you view parameter “rSt” in the upper display.

3. Press the ENTER key.

4. Press ▲ or ▼ keys to toggle between NO and

YES.

• NO retains current memory.

• YES clears all memory

5. Press the ENTER key to confirm selection and to

return to measurement mode.

Figure 41: Reset to factory

defaults

49

Instruction Manual PD 300

9 PROBE CARE AND MAINTENANCE

9.1 pH Electrode car e

Your pH electrode should be kept clean and free from dirt and contamination. Probes that are

not clean may provide slow or unusual readings. With proper care and normal usage, the pH
electrode will need to be replaced every 6 to 18 months on average. NOTE: For specialty

electrode care, consult the instruction manual included with your electrode.

pH electrode storage

For best results, always keep the pH bulb wet. Use the protective electrode storage bottle or

rubber cap filled with electrode storage solution to store your electrode. Also, you can store in

a pH 4 buffer with 1/100 part of saturated KCl. Other pH buffers are OK for short term storage,

but NEVER use distilled water for storage.

After measuring

1. Rinse the pH electrode in de-ionised water.

2. Store the electrode as recommended above in “pH electrode storage,” or as

recommended by the electrode manufacturer.

3. Prior to next use, rinse the liquid junction with de-ionised water and shake dry – never

wipe the electrode.

NOTE: If this does not restore electrode to normal response, see “Reactivating the pH

electrode” section below.

pH electrode cleaning

• Salt deposits: Dissolve the deposits by immersing the electrode in warm tap water for

ten to fifteen minutes. Thoroughly rinse with distilled water.

• Oil/Grease film: wash electrode pH bulb gently in detergent and water. Rinse

electrode tip with distilled water or use a general purpose electrode cleaner (see

Accessories).

• Clogged reference junction: Heat a diluted KCl solution to 60 to 80 °C. Place the

sensing part of the electrode into the heated solution for about 10 minutes. Allow the

electrode to cool in some unheated KCl solution.

• Protein deposits: Prepare a 1% pepsin solution in 0.1 M of HCl. Set the electrode in

the solution for five to ten minutes. Rinse the electrode with distilled water.

50

Instruction Manual PD 300

Reactivating the pH electrode

If stored and cleaned properly, your pH electrode should be ready for immediate use. However,

a dehydrated bulb may cause sluggish response. To rehydrate the bulb, immerse the

electrode in a pH 4 buffer solution for 10 to 30 minutes. If this fails, the electrode requires

activation. Never touch or rub glass bulb. Contact builds up an electro-static charge.

pH electrode activation (for glass body electrodes only)

WARNING: Only qualified persons proficient with the safe handling of dangerous chemicals

should perform the procedure below. Provide proper containers, fume hoods, ventilation, and

waste disposal. Safety goggles and protective clothing must be worn while performing this

procedure. If possible, replace with another electrode instead of performing this re-activation

procedure.

1. Dip or stir the pH electrode in alcohol for 5 minutes.

2. Leave the electrode in tap water for 15 minutes.

3. Dip and stir the electrode in concentrate acid (such as HCL or H

) for five minutes.

2SO4

4. Repeat Step 2.

5. Dip and stir in strong base (NaOH) for five minutes.

6. Leave for 15 minutes in tap water.

7. Now test with standard calibration buffer solutions to see if the electrode yields

acceptable results. You may repeat step 3 through 6 up to three times for better

response. If the response does not improve, then your electrode is no longer functioning.

Replace with a new electrode – call your distributor for information.

51

Instruction Manual PD 300

9.2 Dissolved Oxygen Principle

The probe is a galvanic measuring element which produces an output proportional to the

oxygen present in the medium in which it is placed. The galvanic probe design lets you take

measurements immediately – without the typical 15 minute wait of other dissolved oxygen

probes.

The probe consists of two parts:

• An upper part consisting of an anode, a cathode, and cable.

• A lower part consisting of a membrane cap, membrane, and electrolyte solution.

See Figure 42.

Oxygen diffuses through the membrane onto the cathode, where it is consumed. This process

produces an electrical current which flows through the cable to the meter. The electric current

produced is proportional to the oxygen that passes through the membrane and the layer of

electrolyte. This makes it possible to measure the partial pressure of oxygen in the sample at

a given temperature.

Since the DO in the sample is consumed by the cathode it is essential that a new sample must

flow past the membrane of the probe to prevent the occurrence of false readings. The probe

uses very little oxygen for its measurement. This enables it to function correctly with liquid

movement as low as 2.5 cm/sec.

The permeability of the membrane to oxygen varies greatly with temperature. Therefore

compensation is needed for this variation. The DO probe comes with an in-built Temperature

Compensation for the membrane variation.

52

Instruction Manual PD 300

9.3 Probe Care and Maintenance

Under typical operating conditions, the D O probe should last for several years. Proper

care and maintenance will help you receive the maximum probe life and ensure more accurate

readings.

Since any deposits on the membrane surface act as a barrier to oxygen diffusing through the

membrane, the membrane must be cleaned at regular intervals to assure maximum reliability.

After using the probe, rinse the probe in clean water and wipe it with a soft cloth or paper to

avoid any hardening of deposits. If growth develops on the probe, use a disinfecting chemical

to clean.

NOTE

Although the membrane is strong and not easily damaged, wipe it gently while cleaning it. If
the membrane is damaged or torn, the probe will no longer function.

There are no special probe storage requirements.

53

Instruction Manual PD 300

9.4 Membrane Housing Replacement

Replacement of the membrane cap housing/membrane is

required only when you cannot calibrate the probe, or if the

membrane is damaged.

Typical membrane damages are punctures or wrinkles

caused during measurements or cleaning. For more

information see Trouble-Shooting Guide section on page 60.

Your new DO probe comes with a replacement membrane

housing. To order more replacement membrane housing, ,

see the Accessories section on page 63.

9.4.1 To replace the membrane cap (with pre­installed membrane)

Replacement is much easier with single membrane housing.

Simply unscrew the old membrane cap housing, add solution

to the new housing, and screw the new cap housing in place.

1. Fill the membrane cap housing with electrolyte solution

and inspect the bottom for leaks. If the solution drops

are leaking from the membrane, use a new cap housing.

2. If the assembly is leak-free, fill the membrane cap

housing with electrolyte to the brim.

3. Tap the side of the housing gently to remove any air

bubble that may be sticking to the membrane

4. Screw the cap onto the probe. Excess electrolyte will

drain out.

Figure 42: DO Probe, membrane

cap housing & probe guard

5. Replace probe guard.

6. Calibrate the probe (see section 4) after the % saturation readings have stabilised.

54

Instruction Manual PD 300

9.5 Membrane/O-ri n g Replacement (Optional Procedure)

It is recommended only experienced service personnel can perform this procedure.

This procedure is

OPTIONAL, and should only be performed if you have new membrane and

O-ring. You are also required to have a membrane installation tool. These items are available

as optional accessories in the Accessories section.

1. Pull off the probe guard. See figure on right.

2. Unscrew the membrane cap from the probe.

3. Hold the probe under hot running water and brush away the

white oxide on the cylindrical anode with a stiff plastic brush –

do not use metal cleaning material.

4. If the cathode has any deposits, remove them with a light

scouring powder. Do not polish the cathode.

5. Using the installation tool, unscrew and remove the membrane

lock from the membrane cap. See Figure 44.

6. Remove the membrane and O-ring. Discard both.

7. Rinse the membrane cap and membrane lock in tap water.

8. Install a new O-ring inside the membrane cap.

9. Install a new membrane. Make sure the membrane covers the

O-ring all around its circumference. See Figure 45.

Figure 43: DO Probe & its

various parts

55

Instruction Manual PD 300

10. Using the installation tool, screw the membrane

lock back into the cap. Tighten the lock firmly over

the membrane and O-ring, but do not over tighten.

Close

Installation tool

Open

11. Inspect the membrane for wrinkles. If wrinkles

exist, remove the membrane and repeat steps 8 –

11.

Insert installation

12. Fill the membrane cap with water and inspect the

bottom for leaks. If water drops are leaking from

the membrane, re-seal the membrane on the O-

ring (repeat steps 8 – 11, for membrane

replacement only).

tool into slots on
membrane lock.
Then unscrew
membrane lock
from membrane
cap

13. If the assembly is leak-free, empty the water and

fill the membrane cap with electrolyte to the brim.

14. Tap the side of the housing gently to remove any

air bubble that may be sticking to the membrane.

Figure 44: Use tool to take out (or

put in) membrane

15. Screw the cap onto the probe. Excess electrolyte

will drain out.

16. Replace probe guard.

17. Calibrate the probe (see section 4) after the %

saturation readings have stabilised.

NOTE

Membranes can only be used once. When a membrane
cap is screwed onto the probe, the membrane is
stretched by the cathode. If the same O-ring and the
membrane is used a second time it will not fit
perfectly onto the cathode. This will result is erratic
readings.

56

Figure 45 : Membrane cap housing

with O-ring & membrane

Instruction Manual PD 300

9.6 Electrolyte Solution

The electrolyte solution in your probe’s cap will deplete on usage and will need to be replaced

periodically.

Your new DO probe comes with accessories of one 50-ml replacement electrolyte solution and

a spare membrane cap. The replacement electrolyte comes premixed and ready to use. To

order more electrolyte solution, see Accessories section.

57

Instruction Manual PD 300

9.7 DO Probe Troubleshooting Table

When experiencing difficulties with the equipment, keep in mind of the following:

1. Check for the obvious, such as physical condition of the probe, any signs of damage to

the cable, power and signal connections etc.

2. Determine whether it is the probe, meter or the surrounding environment that is causing

the problem.

The following troubleshooting table identifies most of the problems likely to occur:

Problem Probable Causes Solution

1. Fluctuating readings
when probe is shaken
or bumped lightly or
when membrane is
touched.

2. With membrane cap
removed and probe
internals thoroughly
dry, the reading from
the probe is not zero
and/or is erratic.

Probe has lost electrolyte – a
sloshing noise will be heard
when the probe is shaken.

Torn or damaged membrane.

Wet connections in the wiring
or within probe. See Problem

2.

Moisture has entered the
system – either into the probe
itself or at junctions or points
in the cable. This moisture
creates a secondary galvanic
action in addition to that
produced by the probe and
results in non-zero or erratic
readings.

Determine whether it is a physical or
electronic problem with the probe.

Unscrew the membrane cap, discard
the electrolyte, membrane and O­ring.

Dry the internals of the probe,
especially the cathode with a soft
cloth.

Switch the meter ON and observe the
display.

If the display reads zero, the probe
and cable circuitry are alright.
Service probe and change
membrane.

If the display does not read zero, but
some other value, then there is
probably moisture somewhere. See
Problem 2.

Locate the source of moisture by
process of elimination. If moisture
has entered a junction box or a cable
joint, thoroughly dry out the area and
take measures to prevent
reoccurrence.

58

Instruction Manual PD 300

Problem Probable Causes Solution

3. It is not possible to
calibrate the probe in
air – the display will
not read high enough
after fully adjusting the
offset.

4. Display values are
erratic when
membrane is lightly
touched. Membrane
has bulged outwards.

Probe has dried out – no
electrolyte inside.

Probe is overdue for servicing
– excessive build-up of anode
oxide.

A deposit has built-up on the
silver cathode, which is
inhibiting the reduction of
oxygen at its surface.

The membrane has been
damaged.

The breather hole has become
plugged. This prevents
release of internal pressure
due to expansion of electrolyte
caused by the probe being
warmed up in the sun, for
example.

NOTE: The cathode must not be polished – the surface must remain dull (do not use a wire

brush).

Service probe and change
membrane. Use a stiff nylon brush to
remove the oxide built-up from the
anode. Do not use a wire brush. It is
only necessary to remove the loose
oxide layer. If it is suspected that the
anode is badly corroded, replace with
a new DO probe. Remember to
tighten the nut under the anode
before fitting a new anode.

If it is suspected that a deposit is
coating the silver cathode, clean the
cathode with 400 grit wet/dry emery
paper or with some scouring powder.
The deposit is sometimes visible as a
brownish stain on the surface of the
cathode.

If the membrane has been damaged
change it and service the probe.

If the breather hole is blocked, clear
hole with a pin or fine gauge wire.
Change the membrane and service
the probe.

59

Instruction Manual PD 300

10 TROUBLE SHOOTING GUIDE

Problem Cause Solution

Press ‘ON’ key but no
display

Not responding to key
press

Unstable readings a) Insufficient electrolyte in probe.

“OR” or “UR” on
upper display

Temperature reading
erratic or lower
display reads “OR”

Slow response a) Dirty / Oily probe. a) Clean probe. See Probe Care

a) Batteries not in place

b) Batteries not in correct polarity

(+ and – position).

c) Weak batteries

a) HOLD mode in operation.

b) Damaged key pad.

c) Internal program error.

b) Air bubbles in probe.

c) Dirty probe.

d) Probe not deep enough in

sample.

e) External noise pickup or

induction caused by nearby
electric motor.

f) Broken probe.

a) Probe is shorted.

b) Probe is in out-of-range (OR) or

under range (UR) condition.

c) Broken probe.

a) Temperature of solution is out

of range.

a) Check that batteries are in place

and making good contact.

b) Re-insert batteries with correct

polarity.

c) Replace batteries.

a) Cancel HOLD mode by

pressing Hold key.

b) Return to dealer.

c) Reset all internal programs by

reinserting batteries.

a) Fill probe with reference

electrolyte.

b) Tap probe to remove bubbles.

c) Clean the probe and re-

calibrate.

d) Make sure sample entirely

covers the probe sensors.

e) Move or switch off interfering

motor.

f) Replace probe.

a) Test probe. Make sure probe is

fully connected to meter.

b) Use different solution.

c) Replace probe. See

Accessories section.

a) Heat or cool solution.

& Maintenance section.

b) Check membrane of DO probe.

Replace if necessary

60

Instruction Manual PD 300

11 ERROR MESSAGES

LCD Display Indicates Cause Solution

Err annunciator Unrecognised input

CAL & Err
annunciators on /
Buffer and
electrode
indicators blink.

Battery indicator
blinks

from keypad

Calibration error. Wrong value input at

Low battery level. Need new batteries or

Wrong input in selected
mode.

calibration.

Dirty probe.

battery connection is
bad.

Release key. Select valid
operations depending on
mode.

Check your input value,
clean probe.

See Calibration or Probe
Maintenance section.

Clean battery contacts.
Replace batteries with fresh
ones, noting polarity.

If an error message appears in the primary display (the upper row of larger digits), switching off the

meter and switching it on again may eliminate the error message.

If error persists, or the meter shows incorrect values, return the meter. See Warranty and Return of

Items sections.

For a complete diagram of the display, see page 2.

61

Instruction Manual PD 300

12 SPECIFICATIONS

pH

Dissolved Oxygen

% Saturation of
Oxygen

Temperature

Salinity Correction

Barometric
Pressure
Correction (mm Hg)

DO Probe Galvanic with integral Temperature Sensor

Response Time 40 seconds to achieve 93% of the reading

No. of DO Calibration Points Single point at 100% in saturated air or air-saturated water

Temperature Compensation Automatic or manual from 0 to 100 °C

pH Calibration Up to 5 points (pH 1.68, 4.01, 7.00, 10.01 & 12.45)

pH Slope & Offset Display Yes

Operating Temperature Range 0 to 50 °C

HOLD function Yes

Auto-Off function 20 minutes after last key press

Averaging/Stability function Selectable

Display Customised Dual LCD

Back Lit Display Yes

Inputs BNC for pH, 6-pin military type for DO & Temperature

Power Requirements four 1.5 V AAA-sized batteries (included)

Battery Life > 100 hours continuous use

Dimensions Meter: 19L x 9.5W x 5.7H cm (7.5”x3.75”x2.25”)

Shipping weight Meter: 0.92 kg (2.0 lbs)

Range
Resolution
Relative accuracy

Range
Resolution
Relative accuracy

Range
Resolution
Relative accuracy

Range
Resolution °C
Resolution °F
Relative accuracy

Range
Resolution
Method

Range
Resolution
Method

-2.00 to 16.00 pH

0.01 pH
±0.01 pH

0.00 – 20.00 mg/L or ppm

0.01 mg/L; 0.01 ppm
± 1.5% of Full Scale

0.0 – 200.0 %

0.1 %
± 1.5% of Full Scale

-10.0 to 110.0 °C, (14.0 to 230°F)

0.1°C

0.1°F (14.0°F – 199.9°F) and 1°F(200°F to 230°F)
± 0.3°C (± 0.5°F)

0.0 – 50.0 ppt

0.1 ppt
Automatic correction after manual input

500 to 1499 mm Hg or 66.6 to 199.9 kPA
1 mm Hg or 0.1 kPA
Automatic correction after manual input

Case: 23.3L x 21.6W x 7.0H cm (9.17”x8.5”x2.8”)
Probe: 17.3L x 3.2 Dia cm (6.81”x1.26”dia) , with 3-m cable

Carrying case with meter: 2.2 kg (4.85 lbs)

62

Instruction Manual PD 300

13 ACCESSORIES

Replacement Meters and accessories

Eutech Instruments

Item Eutech Instruments

Ordering Code

Waterproof CyberScan PD 300 portable pH/DO meter (with backlit) – with pH
electrode (EC-DA93506-03B), DO probe with built-in temperature sensor (EC­DOHANDYNEW, 1 assembled membrane cap housing, 50-ml refilling
electrolyte & hard plastic carrying case with pH calibration solutions (EC­PHWP-KIT).

Galvanic Dissolved Oxygen probe with built-in temperature sensor and 3­meter (10-ft) cable.

Submersible Gel-filled pH combination electrode with 15-cm ABS guard, single
annular ceramic junction and 3-meter cable length

General Purpose Plastic-body Gel-Filled “3-in-1” pH/Temp. Combination
Electrode, 12x110mm, BNC connector, 1m cable length.

Temperature probe for CyberScan PD 300 meter EC-PHWP-TEM01W

pH Carrying kit set – hard plastic carrying case comprises of 1 x pH 4.01, pH

7.00, pH 10.01 buffer solutions (60-ml), and 1 x empty rinse water bottle (480-

ml)

Soft carrying pouch for meter EC-POUCH-02

Membrane & O-ring (pack of 5) 01X241603

Assembled Membrane Cap Housing 15X241402

Membrane removal tool 15X241502

Electrode Guard Removal Tool 15X241504

DO Refilling Electrolyte (50ml) 01X211226

EC-PDWP300/03K

EC-DOHANDYNEW

EC-DA93506-03B

EC-FE73528-01W

EC-PHWP-KIT

63

Instruction Manual PD 300

Oakton Instruments

Item Oakton Instruments

Ordering Code

PD 300 meter with DO/Temp probe (35640-50) and pH probe (35805-23) 35632-00

PD 300 meter only 35632-02

PD 300 meter with DO/Temp probe (35640-50) and pH probe (35805-23),
electrode maintenance kit (35640-80), pH calibration solutions, and hard
carrying case.

Single-junction pH electrode, BNC, ABS body, 25-mm diameter, 10 ft (3 m)
cable

Double-junction pH electrode, BNC, ABS body, 25-mm diameter, 10 ft (3 m)
cable

Submersible DO/Temp electrode with 10 ft (3 m) cable 35640-50 (also

Submersible DO/Temp electrode with 25 ft cable 35640-52 (also

Submersible DO/Temp electrode with 50 ft cable 35640-54 (also

Submersible DO/Temp electrode with 100 ft cable 35640-56 (also

Membrane cap assembly (membrane, o-ring, membrane lock, bottom cap) 35640-72

Maintenance kit for DO electrode. Two membrane cap assemblies (35640-72)
and a 30-mL bottle of electrolyte.

Membrane installation tool. Required for 35640-74 & 35640-75 35640-79

Electrolyte solution, 500 mL 35640-71

Replacement membranes, pack of 5 35640-74

Replacement membranes, pack of 25 35640-75

Hard carrying case 35632-98

Temperature probe for pH or temperature only reading with PD 300 meter.
Note: DO reading is not possible when this probe is used.

35632-60

35805-23

35805-24

includes 35640-80)

includes 35640-80)

includes 35640-80)

includes 35640-80)

35640-80

35618-05

64

Instruction Manual PD 300

Calibration Solutions

Item Eutech Instruments

Order Code

pH 4.01 buffer solution, 480 ml bottle (1 pint) EC-BU-4BT 00654-00

pH 7.00 buffer solution, 480 ml bottle (1 pint) EC-BU-7BT 00654-04

pH 10.01 buffer solution, 480 ml bottle (1 pint) EC-BU-10BT 00654-08

pH 4.01 buffer sachets, 20 ml x 20 pcs. EC-BU-4BS 35653-01

pH 7.00 buffer sachets, 20 ml x 20 pcs. EC-BU-7BS 35653-02

pH 10.01 buffer sachets, 20 ml x 20 pcs. EC-BU-10BS 35653-03

pH De-ionised water rinse sachets, 20 ml x 20 pcs EC-RIN-WT 35653-00

pH sachet assortment pack – 5 each of pH 4.01,
pH 7.00, pH 10.01 and de-ionised water sachets
per box.

Protein cleaning solution for pH electrode EC-DPC-BT 00653-06

Storage solution for pH electrode EC-RE-005 00653-04

EC-AST-PK 35653-04

Oakton Instruments

Order Code

Item Oakton Instruments

Ordering Code.

Zero oxygen solution, 500 mL 00653-00

Premixed electrolyte solution, 500 mL 35640-71

Electrolyte power (58.5 g) 35640-70

65

Instruction Manual PD 300

14 ADDENDUM 1: DISSOLVED OXYGEN & METER T HEORY

Dissolved Oxygen (DO) refers to the volume of oxygen that is contained in water. There are

two main sources of DO in water: from atmosphere and photosynthesis. Waves and tumbling

water mix air into the water where oxygen readily dissolves until saturation occurs. Oxygen is

also produced by aquatic plants and algae as a by-product of photosynthesis.

The amount of DO that can be held by water depends on 3 factors: water temperature, salinity,

and atmospheric pressure.

1. Amount of DO increases with decreasing temperature (colder water holds more oxygen).

2. Amount of DO increases with decreasing salinity (freshwater holds more oxygen than

saltwater does).

3. Amount of DO decreases with decreasing atmospheric pressure (amount of DO

absorbed in water decreases as altitude increases).

The chart below shows the solubility of DO in mg/L in water at various temperatures.

Solubility of oxygen in water con t act with water saturated air at

16

14

12

10

8

6

Solubility mg/L

4

2

0

0 102030405060

standard atmospheric pressure

Temperature °C

Figure 46: DO Solubility in Water vs Temperature °C

66

Instruction Manual PD 300

15 ADDENDUM 2: PRESSURE VS ALTITUDE TABLE

Barometric pressure affects DO readings, therefore this meter lets you enter the correct

barometric pressure at your altitude. If you do not have equipment that lets you measure the

exact barometric pressure at your altitude, you can estimate it using the chart below.

If you change the barometric pressure setting from its factory setting (760 mm Hg), the %

saturation calibration value in air will automatically adjust to a value other than 100% (see

“corrected % saturation value” column below). The adjusted value is correct for the new

barometric pressure setting.

See page 37 for information on how to adjust the barometric pressure.

Pressure vs Altitude

ALTITUDE

feet meters

0 (sea level) 0 (sea level) 760 100

500 152.4 746 98.1

1000 304.8 732 96.3

1500 457.2 720 94.7

2000 609.6 707 93.0

2500 762.0 694 91.3

3000 914.4 681 89.6

3500 1066.8 668 87.8

4000 1219.2 656 86.2

4500 1371.6 644 84.6

5000 1524.0 632 83.0

5500 1676.4 621 81.6

6000 1828.8 609 80.0

PRESSURE (mm

HG)

CORRECTED %

SATURATION

VALUE

(1 feet ~ 0.3048 meters)

67

Instruction Manual PD 300

16 ADDENDUM 3: METER FACTO RY DEFAULT SETTINGS

Resetting the meter to factory default settings clears all calibration data and most other setup

functions you might have changed. The following settings will remain as you have set them:

• Temperature unit of measure (°C or °F)

• The temperature offset calibration value.

NOTE

DO and pH data are cleared separately from each other.

• To clear pH data, see Sub group P4.0 on page 36.

• To clear DO data, see Sub group P7.0 on page 49.

Type Parameter P No. Default Remarks

pH parameters

CAL View pH calibration data P1.1 –– Calibration data f or 1st buffer, pH 1.68
P1.2 –– Calibration data for 2nd buffer, pH 4.01
P1.3 –– Calibration data for 3rd buffer, pH 7.00
P1.4 –– Calibration data for 4th buffer, pH 10.01
P1.5 –– Calibration data for 5th buffer, pH 12.45
ELE View electrode offset P2.1 0.00 mV No offset adjustment
View electrode slope P2.2 100.0 % No slope adjustment
COF Ready indicator P3.1 Ready On Ready indicator on; auto endpoint off
# pH calibration points P3.2 3 Selects number of calibration points.

°C or °F P3.3 No default °C or °F remains as selected
rSt pH factory default P4.0 No Retains your current settings

DO parameter

dPr Barometric pressure inputs. P1.1 Hg Hg or Pa.
760 mm Hg Adjustable from 500 – 1499 mm Hg
Salinity adjustment P1.2 0 ppt Adjust from 0 – 50.00 ppt (% only)
OFS Set % saturation offset P2.0 –– Up to ±10% (% only)
CAL View calibration data P3.0 [P2.0] –– ––
ELE View probe slope P4.1 [P3.1] 1.000 ––
View % saturation offset P4.2 [P3.2] 0% offs et ––
View mV = 100% saturation P4.3 [P3.3] 37.0 mV
View mV = 0% saturation P4.4 [P3.4] 0.3 mV
COF Ready indicator P5.1 [4.1] Ready On Ready indicator on; auto endpoint off
Select mg/L or ppm units [P4.2] mg/L mg/L or ppm (mg/L mode only)
°C or °F P5.2 [P4.3] Retains settings °C or °F remains as selected
LCd Adjust back lit display P6.0 [P5.0] 8 Levels 0 to 8 (brightest)
rSt Reset to factory default P7.0 [P6.0] No Yes / no

* Program numbers with “[ ]” are accessed from mg/L (ppm) mode.

Minimum 2 points.

68

Instruction Manual PD 300

17 WARRANTY

This meter is supplied with a three -year meter warranty and six-month pH/ DO probe warranty,

against significant deviations in material and workmanship.

If repair or adjustment is necessary and has not been the result of abuse or misuse within the

designated period, please return – freight pre-paid – and correction will be made without charge.

Eutech Instruments/ Oakton Instruments will determine if the product problem is due to deviations or

customer misuse.

Out of warranty products will be repaired on a charged basis.

Exclusions

The warranty on your instrument shall not apply to defects resulting from:

 Improper or inadequate maintenance by customer

 Unauthorised modification or misuse

 Operation outside of the environment specifications of the products

69

Instruction Manual PD 300

18 RETURN OF ITEMS

Authorisation must be obtained from our Customer Service Department or authorised distributor

before returning items for any reason. A “Return Goods Authorisation” (RGA) form is available

through our authorised distributor. Please include data regarding the reason the items are to be

returned. For your protection, items must be carefully packed to prevent damage in shipment and

insured against possible damage or loss. Eutech Instruments/ Oakton Instruments will not be

responsible for damage resulting from careless or insufficient packing. A restocking charge will be

made on all unauthorised returns.

NOTE: Eutech Instruments Pte Ltd/ Oakton Instruments reserves the right to make improvements in

design, construction, and appearance of products without notice.

70

For more information on Eutech Instruments/ Oakton Instruments’ products, contact
your nearest distributor or visit our website listed below:

Oakton Instruments

P.O Box 5136,
Vernon Hills, IL 60061, USA
Tel: [phone]
Fax: [phone]

[e-mail]

E-mail:

Web-site:www.4oakton.com

Eutech Instruments Pte Ltd.

Blk 55, Ayer Rajah Crescent,
#04-16/24 Singapore 139949
Tel: [phone]
Fax: [phone]
E-mail:

[e-mail]

Web-site: www.eutechinst.com

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