ADWA AD8000 User guide

USER MANUAL

AD8000

pH/mV/EC/TDS/Temperature

Bench Meter

www.adwainstruments.com

1

Dear Customer,

Thank you for choosing an Adwa product.

Please read carefully this manual before starting
operations.

This instrument is in compliance with the EMC directive
2004/108/EC and its standards, and Low Voltage
Directive 2006/95/EC and its standards for electrical
equipments.

For additional technical information, please e-mail us at
[email protected].

2

TABLE OF CONTENTS

Introduction ............................................................... 4

Technical Data .......................................................... 6

Front and Rear Panels ............................................... 8

Operational Guide ................................................... 10

Autoranging ............................................................. 20

pH Calibration ......................................................... 21

Relative mV Calibration ......................................... 28

EC Calibration ......................................................... 29

Good Laboratory Practice ....................................... 34

Setup ........................................................................ 44

Hold Function.......................................................... 50

Probe Maintenance .................................................. 51

Troubleshooting Guide ........................................... 54

Electrodes, Probes and Solutions ........................... 56

3

INTRODUCTION

AD8000 is a microprocessor-based pH, ORP, con­ductivity, TDS and temperature bench meter. Relative
mV feature is also provided.
The autoranging feature of the EC and TDS ranges au­tomatically sets the instrument to the scale with the highest
resolution.
pH measurements are compensated for temperature
effect automatically (ATC) using AD7662 temperature
probe, while the EC readings can be compensated auto­matically (ATC) using the conductivity probe with built­in temperature sensor or manually (MTC). It is also pos­sible to disable the temperature compensation and mea­sure the actual conductivity.
The temperature coefficient is user selectable.
The pH calibration can be performed at 1, 2 or 3 points
with five memorized buffers (pH 4.01, 6.86, 7.01, 9.18,

10.01).
In addition, AD8000 is provided with calibration time­out alarm, GLP feature to view last calibration data and
automatic HOLD feature to freeze the first stable read­ing on the LCD.

4

This model is supplied complete with:

• AD1131B refillable pH electrode with glass body,
BNC connector and 1 m cable

• AD76309 conductivity probe with built-in tempera­ture sensor and 1 m cable

•

AD7662 stainless steel temperature probe, 1 m cable

• pH 4.01 and pH 7.01 calibration buffers (20 ml
sachet each)

• EC calibration solutions at 1413 μS/cm and 12.88 mS/
cm (20 ml sachet each)

• 12 Vdc power adapter

• User manual

5

TECHNICAL DATA

Range -2.00 to 16.00 pH /-2.000 to 16.000 pH

±699.9 mV / ±2000 mV

0.00 to 19.99 μS/cm; 0.00 to 9.99 ppm

20.0 to 199.9 μS/ cm; 10.0 to 99.9 ppm
200 to 1999 μS/cm; 100 to 999 ppm

2.00 to 19.99 mS/cm; 1.00 to 9.99 ppt

20.0 to 199.9 mS/cm; 10.0 to 99.9 ppt

-9.9 to 120.0°C (pH range)

0.0 to 100.0°C (EC range)

Resolution 0.01 pH / 0.001 pH

0.1 mV (±699.9 mV) / 1 mV (±2000 mV)

0.01, 0.1, 1 μS/cm; ppm

0.01, 0.1 mS/cm; ppt

0.1°C

Accuracy ± 0.01 pH / ± 0.002 pH
(@25°C) ± 0.2 mV up to ± 699.9 mV

± 1 mV up to ± 2000 mV

± 1% f.s. (EC/TDS)

± 0.5°C

Relative mV offset range

± 2000 mV

6

pH Calibration

Up to 3-point calibration,

5 buffer available (4.01, 6.86, 7.01, 9.18, 10.01 pH)

EC Calibration Offset at 0.00 μS/cm;

Slope at 1 point with 6 memorized values

(84.0, 1413 μS/cm; 5.00, 12.88, 80.0, 111.8 mS/cm) or

with custom value

Temperature Automatic or manual
Compensation -9.9 to 120.0°C (pH range)

0.0 to 100.0°C (EC range)

Temperature 0.00 to 10.00%/°C
Coefficient (EC) (default: 1.90%/°C)

TDS Factor Selectable from 0.40 to 1.00

(default value: 0.50)

pH electrode AD1131B
EC probe AD76309

with built-in temperature sensor

Power supply 12 Vdc power adapter
Dimensions 230 x 180 x 50 mm
Weight 1.8 kg
Environment 0 to 50°C

RH max. 95% non-condensing

7

FRONT AND REAR PANELS

Front Panel

Rear Panel

8

1. Liquid Crystal Display (LCD)

2. SETUP key, to enter/exit setup mode

3. CFM key, to confirm values

4. CAL key, to enter/exit calibration mode

5. Up arrow key, to manually increase the value of
temperature or other parameters

6. Down arrow key, to manually decrease the value of
temperature or other parameters

7. SHIFT key, to activate the key alternate function
(press and hold first the SHIFT key and then the
second desired key)

8. “lock” key, to freeze current EC range on the LCD
or to clear pH calibration parameter

9. RANGE/MODE key, to select measurement unit
or switch the focused data and to select measure­ment mode or pH resolution

10. ON/OFF key, to turn the instrument ON and OFF

11. HOLD/GLP key, to freeze the first stable reading
on the LCD and to display GLP information

12. Power supply socket

13. Conductivity probe connector

14. Reference input socket

15. BNC connector for pH or ORP electrode

16. Temperature probe socket

9

OPERATIONAL GUIDE

CONNECTIONS

• Plug the 12 Vdc adapter into the power supply socket.

Note: This instrument uses non volatile memory to re-

tain the calibration parameters and all other set­tings even when unplugged.

• For pH or ORP measurements, connect the electrode

to the BNC connector. For electrodes with separate
reference, connect the reference electrode plug to the
reference socket.

• For temperature measurements and automatic tem-

perature compensation, connect the temperature probe
to the appropriate socket.

• For EC and TDS measurements, connect the probe to

the 7-pin connector. Tighten the threaded ring and make
sure the probe sleeve is properly inserted.

10

INSTRUMENT START-UP

• Turn the instrument on by pressing

the ON/OFF button.

• All LCD tags are displayed and a

beep is generated while the instru­ment performs a self test.

Notes:

• The instrument starts in the same range and mode

as it was at power off.

• The RANGE key toggles between pH, mV and
EC ranges.

• The SHIFT and MODE keys change the dis­played information for the selected range.

11

pH MEASUREMENTS

Make sure the instrument has been calibrated before
taking pH measurements.

• Press RANGE to enter pH range.

Note: To change pH resolution press and hold first

SHIFT and then MODE key.

• Immerse the electrode tip and the tem­perature probe approximately 4 cm into
the sample to be tested and stir gen­tly. Allow for the reading to stabilize.

• The pH value is displayed on the pri­mary LCD and the temperature on the
secondary LCD.

• If the pH reading is out of
range, the closest full-scale
value will blink on the pri­mary LCD.

12

• If measurements are taken successively in different
samples, it is recommended to rinse the electrode thor­oughly with deionized or tap water and then with some
of the next sample.

• The pH reading is affected by temperature. In order
to measure the pH accurately, the temperature effect
must be compensated for.

To use the ATC (Automatic Temperature Compensa-

tion) capability of the instrument, connect the
temperature probe, immerse it into the sample as close
as possible to the pH electrode and wait for a few
seconds.

• If the solution temperature is known, MTC (Manual
Temperature Compensation) can be performed by dis­connecting the temperature probe.

The display will show the de­fault temperature of 25°C or
the last temperature reading
with the °C tag blinking.

• The temperature can be adjusted using the arrow keys
(from -9.9°C to 120.0°C).

AD7662

13

ORP (mV) MEASUREMENTS

Oxidation-Reduction Potential (ORP) measurements pro­vide the quantification of the oxidizing or reducing power
of the tested sample.

To correctly perform a redox measurement, the surface
of the ORP electrode must be clean and smooth.

• Press RANGE to enter mV range.

• Immerse the tip of the ORP electrode 4
cm into the sample to be tested and al­low a few seconds for the reading to sta­bilize.

• The instrument displays the mV reading
on the primary LCD and the tempera­ture on the secondary LCD.

• If the reading is out of
range, the closest full-scale
value will blink on the pri­mary LCD.

14

RELATIVE mV MEASUREMENTS

• To enter relative mV mode, from mV (ORP) range,
press and hold first SHIFT and then MODE key.

• The relative mV reading will be displayed on the pri­mary LCD and the current temperature value on the
secondary LCD.

Note: The displayed relative mV reading is the differ-

ence between the current mV input value and
the relative mV offset established in the relative
mV calibration.

CONDUCTIVITY MEASUREMENTS

• Enter the conductivity (EC) measurement range by
pressing the RANGE key.

• Immerse the probe into the solution to
be tested. The sleeve holes must be
completely submerged.

• Tap the probe repeatedly to remove any
air bubble that may be trapped inside
the sleeve.

15

• Allow for the reading to sta­bilize. The primary LCD dis­plays the measurement in
the selected range, while the
temperature is displayed on
the secondary LCD.

• If the reading is out of
range, the full-scale value
(i.e. 199.9 mS) will blink.

• If “lock” was pressed to freeze the LCD range and
the reading is out of range, the full-scale value of the
frozen range will blink.

The EC reading is affected by temperature. Three op­tions are available for temperature compensation:

1. Automatic (ATC): the EC probe features a built-in

temperature sensor, which provides the temperature
reading to automatically compensate the EC and TDS
measurements (from 0.0 to 100.0°C), also using the
selected reference temperature.

2. Manual (MTC): the temperature value can be manu-

ally set using the arrow keys. The compensation is
referenced to the selected reference temperature.
While in MTC mode, the °C tag blinks on the second­ary LCD.

16

3. No compensation (NOTC): the temperature is not

taken into account. The reading displayed on the pri­mary LCD is the actual EC or TDS value.

Notes:

• The default compensation mode is ATC.

• Temperature compensation setting can be ac­cessed by entering the setup menu and selecting
the “tcE” item (see “Setup” section for details).

• If no temperature probe is detected, ATC mode
can not be selected and the instrument displays
only dashes “----” on the secondary LCD.

• If the temperature compensation is active, mea­surements are compensated using the tempera­ture coefficient (default value 1.90 %/°C).

To change the temperature coefficient, enter the
setup mode and select the “tc” item (see “Setup”
section for details).

• If the temperature reading is out of the 0.0 to

100.0°C interval and the ATC option is selected,
the temperature full scale value will be displayed,
together with the °C tag blinking. No tempera­ture compensation will be performed.

• The reference temperature can be set from 15
to 30°C. When the reference temperature is

17

changed, the temperature coefficient must be
manually adjusted by the user.

For example, if α is the coefficient with refer-

ence temperature of 25°C, if changing the tem­perature to 20°C, the new coefficient can be cal­culated with the following formula:

β=α/(1-α/20)

If α=1.90%/°C, then β=2.10%/°C.

• Always set reference temperature to 25°C

when measuring TDS.

TDS MEASUREMENTS

• From EC range, press and hold first SHIFT and then
MODE key. The instrument will switch to TDS mea­suring range.

• The TDS reading will be dis­played on the primary LCD
and the temperature reading
on the secondary LCD.

• If the reading is out of
range, the full-scale value
(i.e. 99.9 ppt) will blink on
display.

18

• If “lock” was pressed to freeze the LCD range and
the reading is out of range, the full-scale value of the
frozen range will blink on LCD.

TEMPERATURE MEASUREMENTS

• To take the temperature measurements while the in­strument is in pH or ORP range, connect the AD7662
temperature probe to the appropriate socket on the
rear panel.

Immerse the temperature probe into the sample and
allow the reading to stabilize.

• For EC and TDS ranges, the AD76309 probe is pro­vided with a built-in temperature sensor.

Note: If the instrument is in pH or ORP range and

AD7662 temperature probe is not connected,

the

ºC tag will blink (manual compensation) even

if the EC probe is connected.

19

AUTORANGING

The EC and TDS scales are autoranging. The meter
automatically sets the scale with the highest possible
resolution.

• By pressing the ”lock” key, the autor­anging feature is disabled and the cur­rent range is frozen on the LCD.

The “Auto” and “Off” (autoranging disabled) mes­sages will be displayed on the LCD for a few sec­onds.

• To restore the autoranging option, press “lock” key
again. The “Auto” and “On” (autoranging enable)
messages will be displayed on the LCD for a few sec­onds.

Note: Autoranging is automatically restored if range is

changed, if setup or calibration mode is entered
and if meter is turned off and back on again.

20

pH CALIBRATION

It is recommended to calibrate the instrument frequently,
especially if high accuracy is required.

The instrument should be recalibrated:

• whenever the pH electrode is replaced

• at least once a week

• after testing aggressive chemicals

• if CAL DUE tags are blinking during measurement

Always use fresh buffers for calibration and clean the
electrode before starting the procedure (see “Probe
maintenance” section).

PREPARATION

Pour small quantities of the buffer solutions into clean
beakers.
For accurate calibration and to minimize cross-contami­nation, use two beakers for each buffer solution: one for
rinsing the electrode and one for calibration.
If measurement will be taken in the acidic range, use pH

4.01 as second buffer, while for alkaline environment

use pH 10.01 or 9.18 as second buffer.

21

PROCEDURE

5 memorized buffers are available for calibration: pH

4.01, 6.86, 7.01, 9.18 and 10.01.

For accurate measurements it is recommended to per­form a three-point calibration. However, at least a two­point calibration is suggested.
Select pH range by pressing RANGE.

THREE-POINT CALIBRATION

• Immerse pH electrode and tem­perature probe approximately 4 cm
into a buffer solution of your choice
(pH 4.01, 6.86, 7.01, 9.18, or 10.01)
and stir gently. The temperature
probe should be close to the pH
electrode.

• Press CAL and the instrument will
display the measured pH on the pri­mary LCD and the “7.01” buffer
on the secondary LCD, together
with “CAL”, “1” and “BUFFER”
tags.

22

• If necessary, use the up and down arrow keys to se­lect a different buffer value.

• The hourglass symbol will blink on the LCD until the
reading is stable.

• When the reading is stable and close to the selected buffer,
the CFM tag will blink.

• Press CFM to confirm calibration.

• The calibration value will be displayed on the primary
LCD and the second expected buffer on the secondary
LCD.

Note: The instrument will automatically skip the buffer

used for the first point. It also skips 6.86 if 7.01
buffer was used and viceversa. Likewise, it will
skip 9.18 if 10.01 buffer was used and viceversa.

23

• After the first calibration point is confirmed, immerse
the pH electrode and the temperature probe approxi­mately 4 cm into the second buffer solution and stir
gently. The temperature probe should be close to the
pH electrode.

• If necessary, use the arrow keys to select a different
buffer value.

• The hourglass symbol will blink on the LCD until the
reading is stable.

• When the reading is stable and close to the selected
buffer, the CFM tag will blink.

• Press CFM to confirm. The calibrated value will be
displayed on the primary LCD and the third expected
buffer value on the secondary LCD.

Note: The instrument will automatically skip the buff-

ers used for the first and second calibration points.

• After the second calibration point is confirmed, im­merse the pH electrode and the temperature probe
approximately 4 cm into the third expected buffer and
stir gently. The temperature probe should be closed to
the pH electrode.

• If necessary, use the arrow keys to select a different
buffer value.

24

• The hourglass symbol will blink on the LCD until the
reading is stable.

• When the reading is stable and close to the selected
buffer, the CFM tag will blink.

• Press CFM to confirm calibration.

• The instrument stores the calibration values and re­turns to normal measurement mode.

Notes:

• If the measured value is not close to the selected
buffer, the “WRONG” and “BUFFER” tags will
blink. Check the buffer used or regenerate the
electrode by following the pH electrode clean­ing procedure described in the “Probe mainte­nance” section. If necessary, change the buffer
or the electrode.

• Blinking “WRONG” & “BUFFER” tags and
“Old” message on the secondary LCD, mean
that inconsistency between new and previous
(old) calibration is detected. Clear calibration pa­rameters by pressing “lock” and proceed with
calibration (the instrument will keep all confirmed
values during the current calibration).

• If “lock” is pressed before the first calibration
point is accepted, the instrument clears all cali-

25

bration parameters and returns to measurement
mode.

• Blinking “WRONG” tag and temperature value
are displayed if the temperature reading is out
of the defined temperature range for the buffer.
Calibration cannot be confirmed in this situation.

TWO-POINT CALIBRATION

Proceed as described in the “Three-point calibration”
section and press CAL after the second calibration point
is accepted. The instrument will memorize the calibra­tion data and return to normal measurement mode.

ONE-POINT CALIBRATION

Proceed as described in the “Three-point calibration”
section and press CAL after the first calibration point is
accepted. The instrument will memorize the calibration
data and return to normal measurement mode.

26

Notes:

• During calibration press
RANGE key to toggle be­tween pH buffer and tem­perature reading on the sec­ondary LCD.

• Each time a buffer is confirmed, the new cali­bration parameters replace the old data of the
corresponding buffer.

• To clear old calibration values, press “lock” be­fore exiting calibration.

27

RELATIVE mV CALIBRATION

• Press CAL from the relative mV
measurement mode. Absolute mV
value is displayed on the primary
LCD and the “AbS” message on the
secondary LCD.

• When the absolute reading is stable, the instrument
asks for confirmation.

• If the reading is out of range, the “WRONG” tag will
be displayed.

• Press CFM to confirm the absolute value. The instru­ment will display 0.0 mV on the primary LCD and
“rEL” message on the secondary LCD. Now the rela­tive mV offset is equal to the absolute mV reading.

• Use the arrow keys to change the displayed relative
mV value.

• Press CFM to confirm the relative mV value. The rela­tive mV offset is displayed on the primary LCD and
“OFF” message on the secondary LCD for a few sec­onds. The instrument returns to measurement mode.

Note: The relative mV value can be changed only

within the relative mV offset range (± 2000 mV).

28

EC CALIBRATION

STANDARD CALIBRATION

EC calibration is a one-point procedure. Selectable cali­bration points are: 0.00, 84.0 and 1413 μS/cm, 5.00, 12.88,

80.0 and 111.8 mS/cm.

• Rinse the probe with calibration solu­tion or deionized water, then immerse
it into the solution. The sleeve holes
must be completely submerged.

• Tap the probe repeatedly to remove
any air bubbles that may be trapped
inside the sleeve.

• To enter EC calibration, select the EC
range and press CAL key.

Note: TDS readings are automatically derived from the

EC readings and no specific calibration for TDS
is needed. Pressing CAL when TDS range is
selected has no effect.

• For zero calibration, simply leave the dry probe in the
air. The “CAL” and “BUFFER” tags light up.

• The primary LCD displays the not calibrated EC read­ing, while the secondary LCD shows one of the avail­able standard values. The hourglass symbol blinks.

29

• If necessary, use the arrow keys to select the desired
standard value.

• When the reading is stable, the CFM tag starts blink­ing. Press CFM to confirm calibration.

• The instrument displays the “Stor” and “Good” mes­sages and returns to measurement mode.

30

Notes:

• If the temperature is
out of range, the
“WRONG BUFFER
TEMP” message
blinks on the LCD.

If the reading is too far from the expected value,
“WRONG BUFFER” blinks.

• For best results choose a standard value for cali­bration close to the sample to be measured.

• During standard calibration the meter uses

1.90%/°C compensation coefficient . If the setup
item “tc” has been set to different value, when
exiting calibration mode, the displayed valued on
the upper LCD might be different from the nomi­nal standard value.

CUSTOM CALIBRATION

It is also possible to perform EC calibration with custom

calibration solution.

• Immerse the probe in the custom calibration solution
and select the EC range.

31

• Press CAL to enter the EC calibra­tion and then the RANGE key to en­ter custom EC calibration mode.

• The “CAL”, “BUFFER” and “Cal
Point Custom” tags light up. The pri­mary LCD displays the not calibrated
temperature compensated EC read­ing, while the secondary
LCD shows the tempera­ture compensated EC read­ing, factory calibrated with
k=1. The hourglass symbol
blinks.

• Using the arrow keys, adjust the EC reading on the
primary LCD to the desired value.

• The maximum adjustment is ± 40% around the sec­ondary LCD reading.

• When the reading is stable,
the CFM tag starts blinking
on the LCD. Press CFM to
confirm calibration.

• The instrument displays the “Stor” and “Good” mes­sages and returns to measurement mode.

32

Notes:

• Zero calibration is not allowed in custom mode.

• The calibrated custom value is considered the
value of the calibration solution at the selected
reference temperature.

• It is possible to set the cell constant value di-

rectly, without following the calibration proce­dure. To set the cell constant enter the setup
mode and select the “CELL” item (see “Setup”
section for details).

• The temperature reading is not used during cus­tom EC calibration.

33

GOOD LABORATORY PRACTICE

GLP is a set of functions that allow data storage (and
retrieval) about the electrode status and maintenance.

All data regarding pH, relative mV and EC calibrations
are stored in the instrument memory.

CALIBRATION TIME-OUT ALARM

The instrument allows to set the number of days (from
1 to 7) before the next required pH calibration. The de­fault setting is “OFF” (disabled).

At start-up the instrument checks if the calibration time­out has expired. If yes, the “CAL DUE” message blinks
to advise the user that a new calibration is required.

Note: If the instrument was not calibrated or all cali-

bration data were cleared, the “CAL DUE”
message is displayed even if the feature is dis­abled in the setup menu.

LAST pH CALIBRATION DATA

The last pH calibration data are stored automatically after
a successful calibration.

34

To view the pH calibration data, from pH measurement
mode press SHIFT and then GLP key. The instrument
will display the date (yyyy.mm.dd) of last calibration.

Use the up arrow key to view all calibration parameters
in the following sequence:

• Time (hh:mm) of the last calibration.

• pH calibration offset value.

35

• pH calibration slope (the GLP slope is the average of
the calibration slopes; the percentage is referred to
the ideal value of 59.16 mV/pH).

• Calibration buffers in the order used for calibration,
together with the corresponding warnings.

36

Notes:

• The “OLd” message displayed beside a buffer
value means that this buffer was not used dur­ing last calibration. Press SHIFT and then
SETUP key to see the old calibration date (or
time, if old calibration date is the same as the
last procedure).

• Each buffer is displayed with the resolution used
during calibration.

• The “no bUF” mes­sage means that cali­bration was performed
at less than five points.

• Temperature compensation mode (ATC or MTC; with
or without temperature probe).

37

• pH resolution during calibration.

• Calibration time-out alarm status. The display shows
“OFF” if the feature is disabled, or the days remaining
before the calibration alarm will be activated (e.g. 5
days), or after the calibration is expired (e.g. -3 days).

• The instrument ID.

38

LAST Relative mV CALIBRATION DATA

Last relative mV calibration data are stored automatically
after a successful calibration.

To view the relative mV calibration, from the relative
mV measurement mode press and hold SHIFT and then
GLP key.

The instrument will display the time (hh:mm) of the last
calibration.

Use the up arrow key to view all logged calibration pa­rameter in the following sequence:

• The date (yyyy.mm.dd).

39

• The Relative mV calibration offset.

• The instrument ID as in the pH GLP mode.

LAST EC CALIBRATION DATA

Last EC calibration data are stored automatically after a
successful calibration.
To view the EC calibration data, from the EC measure­ment mode press and hold SHIFT and then GLP key.
The instrument will display the time of last calibration.

Use the up arrow key to view all logged calibration pa­rameters in the following sequence:

40

• The date.

• Used calibration solution, standard.

• Used calibration solution, custom.

• Cell constant.

41

• Calibration offset factor.

• Reference temperature.

• The temperature coefficient.

• The temperature compensation mode.

• The instrument ID as in the pH GLP mode.

42

Notes:

• If NOTC is selected as temperature compensa-

tion mode during calibration, the temperature co­efficient is not displayed in GLP.

• To return to measurement mode, press and hold
SHIFT and then GLP key at any moment.

• If no calibration has been performed on the se­lected range, the “no CAL” message blinks on
the display.

43

SETUP

Setup mode allows to view and modify the instrument
parameters.

Depending on the selected range, it is possible to view
and/or change specific range parameters and common
parameters (for all ranges).

• Common parameters are: instrument ID, time and date.

• Range specific parameters are: calibration time-out
alarm for the pH range; cell constant, TDS factor, tem­perature coefficient, reference temperature and tem­perature compensation for EC and TDS ranges.

• To enter the SETUP mode, press SETUP key from
measurement mode. The instrument will display the
first parameter of the specific range.

• Select the desired parameter using the arrow keys.

• Press CAL to change parameter value. The selected
parameter will start blinking.

• Press RANGE to toggle between displayed param­eters.

• Use the arrow keys to increase or decrease the dis­played value.

44

• Press CFM to save the modified value or CAL to es­cape without saving.

• Use the arrow keys to select the next/previous pa­rameter.

SETTING COMMON PARAMETERS

Instrument ID

• Press CAL when the instrument ID is displayed. The
instrument ID (0000 to 9999) will start blinking.

• Use the arrow keys to change the value.

• Press CFM to save the new instrument ID value, or
CAL to escape without saving.

Current time

• Press CAL when the cur­rent time is displayed. The
hour will start blinking.

• Use the arrow keys to
change the hour.

45

• Press RANGE. The minutes
will start blinking.

• Use the arrow keys to
change the minutes.

• Press CFM to save the new value, or CAL to escape
without saving.

Current date

• Press CAL when the current
date is displayed. The year
will start blinking.

• Use the arrow keys to
change the year.

• Press RANGE. The month
will start blinking.

• Use the arrow keys to
change the month.

• Press RANGE. The day will
start blinking.

• Use the arrow keys to
change the day.

• Press CFM to save the modified value, or CAL to
escape without saving.

46

SETTING RANGE SPECIFIC PARAMETERS

pH Range

Calibration time-out alarm

• Press CAL when the cali­bration time-out is displayed.
Calibration time-out value
(OFF or 1 to 7 days) will
start blinking.

• Use the arrow keys to change the value.

• Press CFM to save the new calibration time-out value,
or CAL to escape without saving.

EC/TDS Range

Cell constant

• Press CAL when the cell
constant is displayed. The
cell constant value will start
blinking.

• Use the arrow keys to change the cell constant (0.500 to

1.700).

• Press CFM to save the new cell constant value, or
CAL to escape without saving.

47

TDS factor

• Press CAL when the TDS
factor is displayed. The
TDS factor starts blinking.

• Use the arrow keys to
change the TDS factor (0.40
to 1.00).

• Press CFM to save the modified value, or CAL to
escape without saving.

Temperature compensation coefficient

• Press CAL when the tem­perature compensation co­efficient is displayed. The
temperature compensation
value will start blinking.

• Use the arrow keys to change the coefficient (0.00 to

10.00 %/

• Press CFM to save the new value, or CAL to escape
without saving.

ºC).

48

Reference temperature

• Press CAL when the ref­erence temperature is dis­played. The reference tem­perature value will start
blinking.

• Use the arrow keys to change the

ture value (15 to 30ºC ).

• Press CFM to save the new value, or CAL to escape
without saving.

Temperature compensation mode

• Press CAL when the tem­perature compensation is
displayed. The temperature
compensation mode will
start blinking.

• Use the arrow keys to change the temperature com­pensation mode (

• Press CFM to save the new setting, or CAL to escape
without saving.

Atc, Mtc or notc).

reference tempera-

49

HOLD FUNCTION

To freeze the first stable reading on
the LCD, press the HOLD key from
measurement mode (pH, mV or EC
range).
The “Auto” and “H” tags will blink on the LCD until
the reading is stabilized.

When the reading is stable, the “H” tag stops blinking
and “Auto” tag turns off. The reading is frozen.

Press the HOLD key again to return the normal mea­surement mode.

50

PROBE MAINTENANCE

pH ELECTRODE PREPARATION

Remove the electrode protective cap.
DO NOT BE ALARMED IF SALT DEPOSITS ARE
PRESENT. This is normal with electrodes and they will
disappear when rinsed with water.
During transport, tiny bubbles of air may form inside the
glass bulb affecting proper functioning of the electrode.
These bubbles can be removed by shaking down the
electrode as you would do with a glass thermometer.
If the bulb and/or junction is dry, soak the electrode in

AD70300 storage solution for at least one hour.

For refillable electrodes:

If the filling solution (electrolyte) level is more than 2.5
cm below the fill hole, add AD7082 electrolyte solution.
For faster response, unscrew the fill hole screw during
measurements.

pH ELECTRODE STORAGE

To minimize clogging and assure a quick response time,
the glass bulb and the junction of the pH electrode should
be kept moist and not allowed to dry out.
Replace the solution in the protective cap with a few

51

drops of AD70300 storage solution.
Note: NEVER STORE THE ELECTRODE IN DIS-

TILLED OR DEIONIZED WATER.

PERIODIC MAINTENANCE

Inspect the probe and cable. The cable used for con­nection to the instrument must be intact and there must
be no points of broken insulation on the cable or cracks
on the pH electrode stem or bulb.
Connectors must be perfectly clean and dry. If any
scratches or cracks are present, replace the probe. For
pH electrodes, rinse off any salt deposits with water.

For refillable electrodes:

Refill the electrode reference chamber with fresh
AD7082 electrolyte solution. Allow the electrode to
stand upright for 1 hour. Follow the storage procedure.

pH ELECTRODE CLEANING PROCEDURE

Soak the electrode tip in deionized water for approxi­mately 30 minutes.

IMPORTANT: After performing a cleaning procedure,
rinse the electrode thoroughly with deionized water and
soak it in AD70300 storage solution for at least 1 hour

52

before taking measurements.

EC PROBE MAINTENANCE

After measurements, rinse the probe with clean water.
If a more thorough cleaning is required, remove the probe
sleeve and clean the probe with a cloth or a nonabrasive
detergent.

Make sure to reinsert the sleeve onto the probe properly

and in the right direction.

After cleaning the probe, recalibrate the instrument.

53

TROUBLESHOOTING GUIDE

SYMPTOM

Slow response/

excessive drift
measuring pH.

Reading

fluctuate up and
down (noise).

Out of range in

the mV scale.

The meter does

not accept the
buffer solution
for pH calibra­tion.

PROBLEM

Dirty pH electrode.

Clogged/dirty junc-

tion. Low electro­lyte level (refillable
pH electrodes only).
EC probe sleeve not
properly inserted;
air bubbles inside
sleeve.

Dry membrane/dry

junction.

Out of order pH elec -

trode.

SOLUTION

Soak the electrode

tip in deionized wa­ter for 30 minutes
and then clean the
electrode.

Clean the electrode.

Refill with fresh so­lution (refillable pH
electrodes only).
Properly insert the
sleeve. Tap the
probe to remove air
bubbles.

Soak in AD70300 stor-

age solution for at
least one hour.

snsmfl

Follow the cleaning

procedure. If neces­sary, replace the
electrode.

54

The display

shows blinking
“-2.00 pH” or
“16.00 pH” .

The display

shows blinking
“+/-2000 mV” .

The display

shows blinking
EC or TDS
reading.

The meter does

not work with
temp. probe.

The meter fails to

calibrate or gives
faulty readings.

At start-up all

LCD tags fixed.

“Err xx” error mes-

sage displayed.

pH reading out

of range.

mV reading out

of range.

EC or TDS read-

ing out of range.

Broken temp.

probe.

Broken

electrode.

One key is

blocked.

Internal error.

Recalibrate the meter.
Make sure the sample

is within the specified
pH range. Check
electrolyte level and
electrode general state.

Electrode not

connected.

Recalibrate the meter.

Make sure the sample
is within the specified
range and the “lock”
key was not pressed.

Replace the tempera-

ture probe.

Replace the electrode.

Check the keyboard or

contact the vendor.

Power the meter off

and on again. If the er­ror persists, contact
the vendor.

55

ELECTRODES, PROBES AND SOLUTIONS

AD1131B Refillable pH electrode with glass body, pro-

tection bottle, BNC connector and 1 m cable.

AD1230B pH electrode with Epoxy body, tip protection

bottle, BNC connector and 1 m cable.

AD3230B ORP electrode with Epoxy body, tip pro-

tection bottle,BNC connector and 1 m cable.

AD76309 Conductivity probe with built-in tempera-

ture sensor, DIN connector and 1 m cable.

AD7662 Stainless steel temperature probe with 1 m

cable.

AD70004P pH 4.01 buffer solution, 20 ml sachet, 25 pcs.
AD7004 pH 4.01 buffer solution, 230 ml bottle
AD70007P pH 7.01 buffer solution, 20 ml sachet, 25 pcs.
AD7007 pH 7.01 buffer solution, 230 ml bottle
AD70010P pH 10.01 buffer solution, 20 ml sachet, 25 pcs.
AD7010 pH 10.01 buffer solution, 230 ml bottle
AD70000P Electrode rinsing solution, 20 ml sachet,

25 pcs.

AD7000 Electrode rinsing solution, 230 ml bottle
AD70031P 1413 μS/cm solution, 20 ml sachet, 25 pcs
AD7031 1413 μS/cm solution, 230 ml bottle

56

AD70030P 12.88 mS/cm solution,20 ml sachet, 25 pcs
AD7030 12.88 mS/cm EC standard solution, 230 ml
AD7033 84 μS/cm EC standard solution, 230 ml
AD7034 80.00 mS/cm EC standard solution, 230 ml

AD7035 111.80 mS/cm EC standardsolution, 230 ml
AD7039 5000 μS/cm EC standard solution, 230 ml

AD7082 Refilling solution, 3.5M KCl, 4x30 ml
AD70300 Storage solution, 230 ml bottle

AD7061 Electrode cleaning solution, 230 ml bottle

57

585960

ADWA INSTRUMENTS Kft.

Alsókikötõ sor 11, 6726 Szeged, Hungary

Tel. [phone]

Fax [phone]

e-mail: [email protected]

www.adwainstruments.com

MANAD8000 09/14