GHM GREISINGER User manual

Operating manual
G 1501
pH / Redox measuring device with
temperature measurement
EN

Table of contents
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B-H86.0.12.DB2-2.1
Table of contents
1 About this documentation.......................................................................................................................... 4
1.1 Foreword .......................................................................................................................................................... 4
1.2 Purpose of the document............................................................................................................................... 4
1.3 Legal notices.................................................................................................................................................... 4
1.4 Correctness of content................................................................................................................................... 4
1.5 Layout of this document................................................................................................................................. 4
1.6 Further information.......................................................................................................................................... 5
2 Safety............................................................................................................................................................... 6
2.1 Explanation of safety symbols....................................................................................................................... 6
2.2 Foreseeable misuse ....................................................................................................................................... 6
2.3 Safety instructions........................................................................................................................................... 7
2.4 Intended use.................................................................................................................................................... 7
2.5 Qualified personnel......................................................................................................................................... 7
3 Description ..................................................................................................................................................... 8
3.1 Scope of delivery............................................................................................................................................. 8
3.2 Functional description..................................................................................................................................... 8
4 The product at a glance............................................................................................................................... 9
4.1 The G 1501...................................................................................................................................................... 9
4.2 Display elements............................................................................................................................................. 9
4.3 Operating elements......................................................................................................................................... 9
4.4 Connections................................................................................................................................................... 10
5 Measurement Basics.................................................................................................................................. 11
5.1 pH measurement........................................................................................................................................... 11
5.1.1 Explanation......................................................................................................................................... 11
5.1.2 pH electrode ....................................................................................................................................... 12
5.1.3 Design.................................................................................................................................................. 12
5.1.4 Further information........................................................................................................................... 12
5.1.5 Choosing a pH electrode .................................................................................................................. 13
5.1.6 Service life........................................................................................................................................... 13
5.1.7 Care and maintenance ...................................................................................................................... 13
5.2 Redox measurement.................................................................................................................................... 14
5.2.1 Explanation......................................................................................................................................... 14
6 Operation and maintenance..................................................................................................................... 15
6.1 Operating and maintenance notices .......................................................................................................... 15
6.2 Battery............................................................................................................................................................. 15
6.2.1 Battery indicator ................................................................................................................................ 15
6.2.2 Changing battery ............................................................................................................................... 16
6.3 Calibration and adjustment.......................................................................................................................... 18
6.4 Calibration and adjustment service............................................................................................................ 23
6.4.1 Certificates .......................................................................................................................................... 23
7 Operation ...................................................................................................................................................... 24
7.1 Commissioning.............................................................................................................................................. 24
7.1.1 Explanation......................................................................................................................................... 24
7.2 Configuration.................................................................................................................................................. 24
7.2.1 Explanation......................................................................................................................................... 24
7.2.2 Opening the configuration menu .................................................................................................... 24
7.2.3 Configuring parameters of the configuration menu..................................................................... 25

Table of contents
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7.2.4 Adjustment of the measuring input ................................................................................................27
7.2.5 Configuring parameters of the adjustment menu .........................................................................28
8 Error and system messages.....................................................................................................................30
9 Disposal.........................................................................................................................................................32
10 Technical data..............................................................................................................................................33
11 Spare parts and accessories....................................................................................................................35
12 Service ...........................................................................................................................................................37
12.1 Manufacturer..................................................................................................................................................37
12.2 Repairs processing........................................................................................................................................37

1 | About this documentation
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1 About this documentation
1.1 Foreword
Read this document carefully and familiarise yourself with the operation of the product
before you use it. Keep this document ready to hand and in the immediate vicinity of
the product so that it is available to the personnel/user for reference at all times in
case of doubt.
The product was developed according to the state of the art and fulfils the require-
ments of the applicable European and national Directives. All corresponding docu-
ments are available from the manufacturer.
Only technically qualified persons are permitted to carry out commissioning, operation,
maintenance and decommissioning. The qualified personnel must have carefully read
and understood the operating manual before beginning any work.
1.2 Purpose of the document
–It provides important information for operating safely and efficiently with the prod-
uct.
–In addition to the quick reference guide with all relevant legal and safety content in
hard copy, this document is a detailed reference option for the product.
1.3 Legal notices
The liability and warranty of the manufacturer for damages and consequential damag-
es are voided with misuse, disregarding this document, disregarding safety notices,
assignment of inadequately qualified technical personnel and arbitrary modifications of
the product.
Only carry out the maintenance and service tasks on this product that are described in
this documentation. In the process, adhere to the specified steps. For your own safety,
only use original spare parts and accessories of the manufacturer. We assume no lia-
bility for the use of other products and resulting damage.
This document is entrusted to the recipient for personal use only. Any impermissible
transfer, duplication, translation into other languages or excerpts from this operating
manual are prohibited.
The manufacturer assumes no liability for print errors.
1.4 Correctness of content
The contents of this document were checked for corrected and are subject to a con-
tinuous correction and updating process. This does not rule out potential errors. In the
event that errors are discovered or in case of suggestions for improvement, please in-
form us immediately via the indicated contact information in order to help us make this
document even more user-friendly.
1.5 Layout of this document
Description
Each chapter is explained at the beginning in the description.

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Prerequisite
All mandatory prerequisites are then listed for each step.
Instruction
Tasks to be carried out by the personnel / user are represented as numbered instruc-
tions. Adhere to the sequence of the specified instructions.
Representation
Shows an illustrative instruction or a configuration of the product.
Formula
Some instructions include a formula for a general understanding of a configuration,
programming or a setting of the product.
Outcome of an action
Result, consequence or effect of an instruction.
Emphases
In order to simplify legibility and provide a clearer overview, various sections / infor-
mation are emphasised.
–1234 Display elements
–Mechanical controls
–Product functions
–Product labels
–Cross-reference [4]
–Foot notes
1.6 Further information
Software version of the product:
–V1.2 or later

2 | Safety
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0
2 Safety
2.1 Explanation of safety symbols
DANGER
This symbol warns of imminent danger, which can result in death, severe bodily injury,
or severe property damage in case of non-observance.
DANGER
This symbol indicates danger for living tissue as well as a variety of materials, which
can be damaged or destroyed when coming into contact with this chemical. Caustic
effect, protective equipment required!
CAUTION
This symbol warns of potential dangers or harmful situations, which can cause dam-
age to the device or to the environment in case of non-observance.
NOTE
This symbol indicates processes, which can have a direct influence on operation or
can trigger an unforeseen reaction in case of non-observance.
2.2 Foreseeable misuse
The fault-free function and operational safety of the product can only be guaranteed if
applicable safety precautions and the device-specific safety instructions for this docu-
ment are observed.
If these notices are disregarded, personal injury or death, as well as property damage
can occur.
DANGER
Incorrect area of application!
In order to prevent erratic behaviour of the product, personal injury and property dam-
age, the product must be used exclusively as described in the chapter Description
[8] in the operating manual.
–The product is not suitable for use in explosion-prone areas!
–The product must not be used for diagnostic or other medical purposes on pa-
tients!
–The product is not intended to come into direct contact with food. For measure-
ment in foods, samples must be taken and discarded after the measurement!
–Not suitable for use with requirements on functional safety, e.g. SIL!

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2.3 Safety instructions
DANGER
Danger of breaking the electrodes!
All electrodes contain glass parts that can cause injuries when broken. There is an el-
evated risk of injury in connection with measurements in foods.
–Inspect the electrode before and after the measurement!
–Always measures in samples for measurements in foods. Discard these samples
after the measurement!
NOTE
This product does not belong in children's hands!
2.4 Intended use
The product is designed for measuring the pH value and Redox by means of suitable
electrodes in water an aqueous media. Temperature compensation takes place auto-
matically with a connected temperature sensor.
Application examples for this are, for example, drinking water, waste water, surface
water, swimming pools, fish breeding and process chemistry.
2.5 Qualified personnel
For commissioning, operation and maintenance, the relevant personnel must have
adequate knowledge of the measuring process and the significance of the measure-
ments. This document makes a valuable contribution to this. The instructions in this
document must be understood, observed and followed.
In order to avoid any risks arising from interpretation of the measurements in the con-
crete application, the user must have additional expertise. The user is solely liable for
damages/danger resulting from misinterpretation due to inadequate expertise.

3 | Description
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3 Description
3.1 Scope of delivery
Please check to ensure the completeness of the product after opening the package.
You should find the following components:
–Quick reference guide
–Handheld measuring device, ready for operation, including batteries
–Electrode GE 114 WD
–Test protocol
3.2 Functional description
The product offers precision, speed and reliability in a compact, ergonomic housing.
Additional impressive features include the dust-proof and waterproof design in ac-
cordance with IP 65/67 and the 3-line illuminated display, which offers overhead dis-
play at the push of a button. The product can be switched on, switched off and config-
ured and the measurements and parameters can be adjusted and held with the oper-
ating elements. The product is equipped with a BNC socket for connection of different
electrodes, as well as with two 4 mm banana sockets for connection of temperature
sensors or a reference electrode.

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4 The product at a glance
4.1 The G 1501
LCD Disply
Front view
Top view
4.2 Display elements
Display
Battery indicator
Evaluation of the battery status
Unit display
Display of units or type of mode, min/max/hold
Main display
Measurement of the current pH value or value for
min/max/hold
Auxiliary display
Corresponding temperature for the displayed pH
value with unit. Measured temperatures are dis-
played with a decimal place, adjusted without.
Bar graph
Progress for calibration and visualisation of the
electrode evaluation
4.3 Operating elements
On / Off button
Press briefly
Switch on the product
Activate / deactivate lighting
Long press
Switch off the product
Reject changes in a menu

4 | The product at a glance
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Up / Down button
Press briefly
Display of the min/max value
Change value of the selected parameter
Long press
Reset the min/max value of the current measure-
ment
Both simultaneously
Rotate display, overhead display
Function key
Press briefly
Freeze measurement (Hold)
Return to measurement display
Call up next parameter
Long press, 2s
Start menu configuration, (ONF appears in the dis-
play
Long press, 4s
Start automatic calibration, (AL appears in the dis-
play
4.4 Connections
BNC connection
Connection for pH electrode
Un/locking with rotating ring on the cable plug
2x 4mm banana
Connection for temperature sensor or reference
electrode
CAUTION
Ensuring water tightness!
The product guarantees protection from spray water, rain or accidental immersion in
water. This protection for the plug connector is only guaranteed when plugged in.
Moisture or contaminants on the contacts can result in incorrect measurement results.
–Protect contacts from soiling and moisture!
–Dry off damp plug connectors as quickly as possible!
NOTE
The temperature measurement can be influenced by conductive liquids on the banana
sockets. We recommend always keeping the connections dry.

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5 Measurement Basics
5.1 pH measurement
5.1.1 Explanation
The pH value describes the acidic or alkaline behaviour of an aqueous solution. A pH
value below 7 is acidic, a value above 7 is alkaline. A pH value of 7 is neutral.
The pH measurement is very precise, but also sensitive. The measured signals are
very weak and high-ohmic. This is the case, in particularly in low-ion media.
NOTE
In order to detect the pH value of a solution, it should always be recorded together
with the measurement temperature, because most liquids change their pH value with
the temperature.
The following must be observed:
–avoid interference, electrostatic charges, etc.
–keep plug contacts clean and dry
–prevent electrodes which do not have any special waterproof versions from ex-
tended immersion above the shaft
–calibrate electrodes sufficiently often. The can range from every hour to several
weeks, depending on the electrode and the application
–Use a suitable electrode

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5.1.2 pH electrode
NOTE
Normally, so-called pH single-rod measuring chains are used. They include all neces-
sary components that are integrated in an electrode.
5.1.3 Design
Fig. 1: pH electrode
1. Coaxial cable
2. Reference electrode
3. Measuring electrode
4. Refill opening
5. Electrolyte
6. Internal buffer
7. Diaphragm
8. Glass membrane / source layer
The diaphragm, which establishes a connection between the electrolyte and the liquid
to be measured, can be designed in different ways. Clogging or soiling of the dia-
phragm is a frequent cause of a malfunctioning or sluggish electrode. Always handle
the glass membrane with extreme care. The so-called source layer forms there. This
is crucial for the measurement and must always be kept moist.
There are also electrodes with integrated temperature sensors.
5.1.4 Further information
A pH electrode is a wear part. If the signal is very slow or the required values are no
longer observed after careful cleaning and possible regeneration, the electrode must
be replaced. When using the electrodes, be aware that various substances in aqueous
solutions can corrode glass and that chemicals can produce a chemical reaction with
the KCl solution in the electrode, which can result in blockage of the diaphragm.
–In solutions that contain proteins, such as for measurements in medical and bio-
logical applications, KCl can cause denaturation of the protein.
–Coagulated paints

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–Solutions that contain high concentrations of silver ions
Substances that accumulate on the glass membrane or the diaphragm affect the
measurement and must be removed regularly. This can be achieved for example with
automatic cleaning systems.
5.1.5 Choosing a pH electrode
The GE 114 WD or GE 100 can be used for most applications. However, some areas
of application require special electrodes.
–GE 100 BNC is a universal electrode with two ceramic diaphragms and liquid elec-
trolyte.
–GE 101 BNC is preferably used for small sample amounts. It comprises a glass
electrode with two ceramic diaphragms and liquid electrolyte.
–GE 104 BNC is preferably used for measurements in low-ionic media, such as
rainwater, aquarium water and deionised water.
–GE 114 WD is a universally applicable, durable and low-maintenance gel elec-
trode with Pellon diaphragm. It can be used for measurements in drinking water,
swimming pools, aquaria and slightly contaminated waste water.
–GE 117 BNC is a temperature-compensated gel electrode with two ceramic dia-
phragms and PH 13.5 cable screw coupling.
–GE 120 BNC is an insertion electrode and is preferably used for measurements in
cheese, fruit and meat. For measurements in products containing proteins, the
electrode must be cleaned with a special cleaner. For this purpose, we recom-
mend the GRL 100 pepsin cleaning solution.
–GE 125 BNC is a waterproof, universally applicable, durable and low-maintenance
gel electrode with ceramic diaphragm. It can be immersed above the shaft for an
extended time.
–GE 151 BNC is a glass electrode and is preferably used in galvanic applications
for paints and lacquers.
–GE 173 BNC is an alkaline-resistant glass electrode with ground diaphragm and
gel electrolyte for chemical and waste water applications.
5.1.6 Service life
The service life of electrodes is normally at least 8 to 10 months. When cared for
properly, this can usually increase to more than 2 years. The actual life will vary de-
pending on the particular application.
5.1.7 Care and maintenance
NOTE
The glass tip of the electrode with the sensitive hydrated layer must be kept moist, e.g.
with 3 mol/l KCl solution in the storage cap. Accidental drying-out of the electrode can
be reversed under certain circumstances after storage for several hours in 3 mol/l KCl,
but this cannot be guaranteed.
NOTE
The GAK 1400 working and calibration set includes all necessary products for calibra-
tion, care and maintenance of the electrode. Normal cleaning takes place with the

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GRL 100 pepsin cleaning solution into which the electrode is immersed for 5 minutes
before being rinsed off with clean water.
NOTE
Crystallisation of the 3 mol/l KCL solution is unavoidable. Crystallised potassium chlo-
ride on the protective cap and shaft can easily be removed with a fingernail or cloth
and is therefore not a defect or grounds for complaint.
Dirty electrodes must be cleaned. The suitable cleaning agents for the pH glass mem-
brane are listed in the table below.
Impurities
Cleaners
General residue
Mild detergent
Inorganic coatings
Commercially available liquid glass clean-
ers
Metal compounds
1 mol/l HCl solution or GRL 100 pepsin
cleaning solution
Oil and grease
Special cleaner or solvent
Biological coatings with protein
Pepsin cleaning solution GRL 100
Resin lignins
Acetone
Extremely resistant residues
Hydrogen peroxide or sodium hypochlo-
ride
The material of the pH electrode must always be protected. Plastic shafts must not be
cleaned in solvents, etc. If in doubt, contact the manufacturer to inquire about suitable
cleaners for the existing electrode. This is also important in the case of aggressive
substances or other substances that are not primarily water-based!
5.2 Redox measurement
5.2.1 Explanation
The Redox potential 0RP specifies the extent to which the measured sample has an
oxidising or reducing effect relative to the standard hydrogen electrode.
This potential is frequently used in swimming pools as a measured variable for the dis-
infecting effect of a chlorination. For aquaria, the Redox value is also an important pa-
rameter, because fish can only live within a specific Redox range. The measurement
is also important in drinking water preparation, waste water monitoring and in industri-
al applications.
Measurement takes place relative to the widespread silver/silver-chloride system with
3 mol/l KCL electrolyte. The measurements can be read directly (mV setting) or auto-
matically with the mVHunit setting and temperature compensation is calculated based
on the standard hydrogen electrode reference system.
Calibration comparable to the pH measurement does not take place for the Redox
measurement. However, the suitability of the electrodes can always be checked with
Redox testing solutions, such as GRP 100.

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6 Operation and maintenance
6.1 Operating and maintenance notices
NOTE
The product and electrode must be handled with care and used in accordance with the
technical data. Do not throw or strike.
NOTE
Plugs and sockets must be protected from soiling.
NOTE
If the product is stored at a temperature above 50 °C, or is not used for an extended
period of time, the batteries must be removed. Leaks from the batteries are avoided as
a result.
NOTE
The electrode should be stored in dry rooms at a temperature between 10 °C and 30
°C. If the storage temperature range is exceeded or undercut, the electrode can be
destroyed. It should always be stored wet in 3 mol/l KCl. Extended storage in distilled
or deionised water will result in depletion of the reference electrolytes.
NOTE
The pH electrode included in the scope of supply should be arranged vertically up-
wards with the connecting cable. A slight angle of inclination does not impair the
measurement.
6.2 Battery
6.2.1 Battery indicator
If the empty frame in the battery display blinks, the batteries are depleted and must be
replaced. However, the device will still operate for a certain length of time.
If the BAT display text appears in the main display, the battery voltage is no longer ad-
equate for operation of the product. The battery is fully depleted.

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6.2.2 Changing battery
DANGER
Danger of explosion!
Using damaged or unsuitable batteries can generate heat, which can cause the batter-
ies to crack and possibly explode!
–Only use high-quality and suitable alkaline batteries!
CAUTION
Damage!
If the batteries have different charge levels, leaks and thus damage to the product can
occur.
–Use new, high-quality batteries!
–Do not use different types of batteries!
–Remove depleted batteries and dispose of them at a suitable collection point!
NOTE
Unnecessary screwing places the water-tightness of the product, among other things,
at risk and should be avoided.
NOTE
Read the following handling instructions before replacing batteries and follow them
step by step. If disregarded, the product could be damaged or the protection from
moisture could be diminished.
Proceed as follows to replace the batteries.
–The product is switched off.
–A suitable PH1 is available
Description
Prerequisites

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Fig. 2: Changing batteries
1. Unscrews the Phillips screws (A)and
remove the cover.
2. Carefully replace the two Mignon AA
batteries (B). Ensure that the polarity
is correct! It must be possible to insert
the batteries in the correct position
without using force.
3. The O-ring (C) must be undamaged,
clean and positioned at the intended
depth. In order to facilitate assembly
and avoid damage, a suitable grease
can be applied.
4. Fit the cover on evenly. The O-ring
must remain at the intended depth!
5. Tighten the Phillips screws (A).
The product is now ready for use again.
Instruction
Outcome of an action

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6.3 Calibration and adjustment
6.3.1.1 Explanation
The following steps describe how to calibrate the product.
To achieve a precise measurement, observe the following points.
NOTE
If possible, the calibration range should overlap the measuring range. To achieve this,
it is recommended to use buffer solutions for measurements as follows:
–below pH 7 uses pH 7.0 and pH 4.0 buffer
–above pH 7 uses pH 7.0 and pH 10.0 buffer
NOTE
Calibrations are only possible in a temperature range from 0 °C to 60 °C! We recom-
mend performing calibration at temperatures between 10 °C and 40 °C.
NOTE
Calibration should be conducted at the same temperature used for the measurement
in the medium. To equalize the temperatures of the buffer solutions and electrode,
they should be stored together for a while in a place that is protected against draught.
NOTE
If a temperature sensor is not connected, measure the temperature of the buffer solu-
tion with a thermometer. The exact value of the buffer solution is temperature depend-
ent and can be determined based on the tables provided.
NOTE
Always use fresh buffer solutions!

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6.3.1.2 Buffer solutions
At least one buffer solution is required to calibrate the product. In the process, you
have the option of using a ready-to-use PHL buffer solution or mixing the solution
yourself with GPH buffer capsules - refer to the instructions.
Colour
10 °C
20 °C
25 °C
30 °C
40 °C
PHL 4.0
Red
4.02
4.00
4.01
4.01
4.01
PHL 7.0
Green
7.06
7.02
7.00
6.99
6.97
PHL 10.0
Blue
10.18
10.07
10.01
9.97
9.89
Ready-to-use buffer solutions in 250 ml dosing bottles with a dosing volume of 20 to 25 ml.
–Plastic bottle
–approx. 100 ml of distilled water
–Buffer capsule
Colour
10 °C
20 °C
25 °C
30 °C
40 °C
GPH 4.0
Orange
3.99
3.99
4.01
4.01
4.03
GPH 7.0
Green
7.06
7.01
7.00
6.99
6.98
GPH 10.0
Blue
10.18
10.06
10.01
9.97
9.89
GPH 12.0
White
12.35
12.14
12.00
11.89
11.71
Buffer capsules for 100 ml buffer solution
1. Fill a plastic bottle with approx. 100 ml of distilled water.
2. Open the buffer capsule carefully by twisting the capsule halves and pulling. It
should be ensured that nothing is spilled. They can also be used without opening
them; opening the capsules only reduces to time for dissolving.
3. Place the buffer capsule and its contents in the plastic bottle.
4. Wait at least 3 hours.
5. Shake well before using for the first time.
Then you can begin with calibration of the product.
Description
Prerequisite
Instruction
Outcome of an action

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6.3.1.3 Automatic pH calibration
The following steps describe how to calibrate the product automatically.
–The product is switched on.
–The pH electrode and, if applicable, a temperature sensor are inserted in the
product.
–Ready-to-use GPH 7.0 buffer solution.
–Ready-to-use GPH 4.0 or GPH 10.0 buffer solution.
NOTE
Automatic calibration can also be carried out with the pre-mixed PHL buffer solutions.
Since the temperature compensation relates to the GPH capsules, an error of a few
hundredths pH should be taken into account, depending on the temperature. Refer al-
so to the differences in the tables of the buffer solutions in Buffer solutions [19].
1. Press the Function key for 4 seconds to open the Calibration menu. (AL appears in
the display.
2. Release the Function key.
3. PK 7 appears in the display.
4. Place the electrode in the GPH 7.0 buffer solution.
5. The product determines the correct value automatically. If the value is deter-
mined, the display flashes and an acoustic signal is issued to indicate a change to
the next calibration point.
6. If the temperature sensor is not inserted, enter the temperature of the buffer solu-
tion by pressing the Up key and Down key and confirm the entry by pressing the
Function key again.
7. PK 4 and PK 10 alternate in the display.
8. Then, rinse the electrode with distilled or deionised water.
9. Place the electrode in the second buffer solution. The product recognises whether
it is a PK 4 or PK 10 buffer solution automatically.
10. If the temperature sensor is not inserted, enter the temperature of the buffer solu-
tion by pressing the Up key and Down key and confirm the entry by pressing the
Function key again.
11. Then, rinse the electrode again with distilled or deionised water.
After successful completion of the calibration the assessment of the electrode condi-
tion is displayed briefly in percent. Then, the current measurement is shown in the
display again. A low value can be the result of the age of the electrode, contaminated
or old buffer solutions or impurities on the BNC connector.
If the calibration is not completed successfully an error message is displayed. (AL ERR.
appears in the display. See Error and system messages [30]. Confirm the error mes-
sage pressing the Function key. The product restarts and the standard value for the ze-
ro point and gradient are restored.
For this purpose, also refer to
Buffer solutions [19]
Description
Prerequisite
Instruction
Outcome of an action