Horiba Scientific LAQUAact D-75G User manual

Instruction Manual
pH/ORP/
Dissolved Oxygen Meter ( D-75G )
Preface
Part names and
basic operation
Measurement
Various functions
Maintenance
How to resolve errors
or troubles
Appendix
Portable pH
・
Water Quality Meter

I
CODE:GZ0000333610F
January, 2018 2017 2018 HORIBA Advanced Techno Co., Ltd.
■Preface
This manual describes the operation of the following instrument.
Be sure to read this manual before using the product to ensure proper and safe
operation of the product. Also safely store the manual so it is readily available whenever
necessary.
Product specifications and appearance, as well as the contents of this manual are
subject to change without notice.
●Warranty and responsibility
HORIBA Advanced Techno Co., Ltd. warrants that the Product shall be free from defects
in material and workmanship and agrees to repair or replace free of charge, at option of
HORIBA Advanced Techno Co., Ltd., any malfunctioned or damaged Product
attributable to responsibility of HORIBA Advanced Techno Co., Ltd. for a period of Two
(2) years from the delivery unless otherwise agreed with a written agreement. In any one
of the following cases, none of the warranties set forth herein shall be extended;
・Any malfunction or damage attributable to improper operation
・Any malfunction attributable to repair or modification by any person not authorized
by HORIBA Advanced Techno Co., Ltd.
・Any malfunction or damage attributable to the use in an environment not specified in
this manual
・Any malfunction or damage attributable to violation of the instructions in this manual
or operations in the manner not specified in this manual
・Any malfunction or damage attributable to any cause or causes beyond the
reasonable control of HORIBA Advanced Techno Co., Ltd. such as natural disasters
・Any deterioration in appearance attributable to corrosion, rust, and so on
・Replacement of consumables
HORIBA Advanced Techno Co., Ltd. SHALL NOT BE LIABLE FOR ANY DAMAGES
RESULTING FROM ANY MALFUNCTIONS OF THE PRODUCT, ANY ERASURE OF
DATA, OR ANY OTHER USES OF THE PRODUCT.
●Trademarks
・Microsoft, Windows, Windows Vista are registered trademarks or trademarks of
Microsoft Corporation in the United States and other countries.
Other company names and brand names are either registered trademarks or trademarks
of the respective companies. (R), (TM) symbols may be omitted in this manual.
Brand (pet name): LAQUAact
Series name: Portable pH Water Quality Meter
Model: D-75G
Model description: pH/ORP/Dissolved Oxygen Meter

Check Items
II
■Check Items
●Items in package
After opening the package, check for damage on the instrument and that the standard
accessories (see below) all exist.
If damage or defects are found on the product, contact your dealer.
Note
・The accessories are not waterproof.
・The supplied alkaline batteries are used to check operation, thus it is possible that the
battery will be run out quickly.
Instrument Instruction manual
(this book)
Quick-start Manual AAA alkaline batteries

Regulations
III
■Regulations
●EU regulations
●Conformable standards
This equipment conforms to the following standards:
●Installation environment
This product is designed for the following environment.
・Overvoltage category II
・Pollution degree 2
●Information on disposal of electrical and electronic equipment and
disposal of batteries and accumulators
The crossed out wheeled bin symbol with underbar shown on the product or
accompanying documents indicates the product requires appropriate treatment,
collection and recycle for waste electrical and electronic equipment (WEEE) under the
Directive 2012/19/EU, and/or waste batteries and accumulators under the Directive
2006/66/EC in the European Union.
The symbol might be put with one of the chemical symbols below. In this case, it satisfies
the requirements of the Directive 2006/66/EC for the object chemical.
This product should not be disposed of as unsorted household waste.
Your correct disposal of WEEE, waste batteries and accumulators will contribute to
reducing wasteful consumption of natural resources, and protecting human health and
the environment from potential negative effects caused by hazardous substance in
products.
Contact your supplier for information on applicable disposal methods.
●Authorised representative in EU
HORIBA UK Limited
2 Dalston Gardens, Stanmore, Middx HA7 1BQ, UK
EMC: EN61326-1
Class B, Basic electromagnetic environment
Safety: EN61010-1
RoHS: EN50581
9. Monitoring and control instruments
Warning: This product is not intended for use in industrial environments. In an
industrial environment, electromagnetic environmental effects may
cause the incorrect performance of the product in which case the
user may be required to take adequate measures.

Regulations
IV
●FCC rules
Any changes or modifications not expressly approved by the party responsible for
compliance shall void the user's authority to operate the equipment.
●Warning
This equipment has been tested and found to comply with the limits for a Class A digital
device, pursuant to part 15 of the FCC Rules. These limits are designed to provide
reasonable protection against harmful interference when the equipment is operated in a
commercial environment. This equipment generates, uses, and can radiate radio
frequency energy and, if not installed and used in accordance with the instruction
manual, may cause harmful interference to radio communications.
Operation of this equipment in a residential area is likely to cause harmful interference in
which case the user will be required to correct the interference at his own expense.
●Korea certification
●
●Taiwan battery recycling mark

Regulations
V
●China regulation
ḽ䇦Ⲻᝅѿ
Meaning of Marking
䝬䞊䜽䛾ព࿡㻌
ᵢḽ䇦䘸⭞൞ѣ঄Ӱ≇ާૂള䬶୤⭫ಞ⭫ᆆӝ૷θḽ䇦ѣཤⲺᮦ
ᆍ㺞⽰⧥ູؓᣚֵ⭞ᵕ䲆ⲺᒪᮦȾ(уᱥ㺞⽰ӝ૷䍞䠅ؓ䇷ᵕ䰪Ⱦ)
㾷䚫ᆾ䘏Ѡӝ૷ᴿީⲺᆿޞૂֵ⭞⌞ᝅӁ亯θԄ࡬䙖ᰛᔶခ㇍
䎭൞䘏Ѡᒪ䲆޻θуՐ㔏⧥ູ⊗ḉȽӰ։ૂ䍘ӝᑜᶛћ䠃ⲺᖧଃȾ
䈭у㾷䳅ᝅᓕᔹᵢ⭫ಞ⭫ᆆӝ૷Ⱦ
This marking is applied to electric and electronic products sold
in the People's Republic of China. The figure at the center of
the marking indicates the environmental protection use period
in years. (It does not indicate a product guarantee period.) It
guarantees that the product will not cause environment
pollution nor serious influence on human body and property
within the period of the indicated years which is counted from
the date of manufacture as far as the safety and usage
precautions for the product are observed. Do not throw away
this product without any good reason.
ᮏ䝬䞊䜽䛿䚸୰⳹ேẸඹ࿴ᅜ䛷㈍኎䛥䜜䜛㟁Ẽ㟁Ꮚ〇ရ䛻㐺⏝䛥
䜜䚸䝬䞊䜽䛾୰ኸ䛾ᩘᏐ䛿⎔ቃಖㆤ౑⏝ᮇ㝈䛾ᖺᩘ䜢ព࿡䛧䜎䛩
䠄〇ရ䛾ရ㉁ಖドᮇ㛫䜢♧䛩䜒䛾䛷䛿䛒䜚䜎䛫䜣䠅䚹䛣䛾〇ရ䛻㛵
䛩䜛Ᏻ඲䜔౑⏝ୖ䛾ὀព䜢䛚Ᏺ䜚㡬䛟㝈䜚䚸〇㐀᪥䛛䜙㉳⟬䛩䜛䛣
䛾ᖺ㝈ෆ䛷䛿䚸⎔ቃởᰁ䜔ேయ䜔㈈⏘䛻῝้䛺ᙳ㡪䜢ཬ䜌䛩䛣䛸
䛿䛒䜚䜎䛫䜣䚹ᮏ〇ရ䜢䜏䛰䜚䛻ᗫᲠ䛧䛺䛔䛷䛟䛰䛥䛔䚹

Regulations
VI
ӝ૷ѣᴿᇩ⢟䍞Ⲻ〦䠅
N
ame and amount of hazardous substance used in a product
䜞Ԭ〦
Unit name
ᴿᇩ⢟䍞
Hazardous substance
䫻
Lead
(Pb)
⊔
Mer
cury
(Hg)
䭿
Cad-
mium㻌
(Cd)
ޣԭ䬢
Hexa-
valent
chrom-
ium㻌
(Cr (VI))
ཐ⓪㚊㤥
Poly
bromo-
biphenyl
(PBB)
ཐ⓪ӂ㤥䟐
Poly
bromo-
diphenyl
ether
(PBDE)
ᵢ։
Main unit
ۑۑۑۑۑ
⭫⊖
Battery
ۑۑۑۑۑ
AC䘸䞃ಞ
AC adapter
*1, *2
ۑۑۑۑۑ
⭫㔼
Cable
*2
ۑۑۑۑۑ
᭥󰶍
Stand
*2
ۑۑۑۑۑۑ
ᢉদᵰ
Printer
*2
ۑۑۑۑۑ
⭫ᶷ
Electrode
*2
ۑۑۑۑ
ᵢ㺞ṲדᦤSJ/T 11364Ⲻ㿺ᇐ㕌࡬Ⱦ
This form is prepared in accordance with SJ/T 11364.
ۑ: 㺞⽰䈛ᴿᇩ⢟䍞൞䈛䜞Ԭᡶᴿൽ䍞ᶆᯏѣⲺ䠅ൽ൞ GB/T 26572 㿺ᇐⲺ䲆䠅㾷
≸ԛсȾ
Denotes that the amount of the hazardous substance contained in all of the
homogeneous materials used in the component is below the limit on the
acceptable amount stipulated in the GB/T 26572.
h: 㺞⽰䈛ᴿᇩ⢟䍞㠩ቇ൞䈛䜞ԬⲺḆжൽ䍞ᶆᯏѣⲺ䠅䎻࠰GB/T 26572 㿺ᇐⲺ
䲆䠅㾷≸Ⱦ
Denotes that the amount of the hazardous substance contained in any of the
homogeneous materials used in the component is above the limit on the
acceptable amount stipulated in the GB/T 26572.
*
1: ᵢ䜞ԬⲺ⧥ֵؓ⭞ᵕ䲆Ѱ10ᒪȾ㻌The environmental protection use period
of this product is 10 years.
*2:
䘿䞃Ԭ
Optional products

For Your Safety
VII
■For Your Safety
●Hazard classification and warning symbols
Warning messages are described in the following manner. Read the messages and
follow the instructions carefully.
●Hazard classification
●Warning symbols
●[DEU] Sicherheitsinformation
Lesen Sie vor der Verwendung des Produkts unbedingt diese Anleitung, um den ord-
nungsgemäßen und sicheren Betrieb des Produkts zu gewährleisten. Bewahren Sie die
Anleitung sicher auf, damit sie bei Bedarf jederzeit zur Hand ist.
Die Inhalt dieser Anleitung können ohne Vorankündigung geändert werden.
●Installationsumgebung
Dieses Produkt ist nicht zum Gebrauch in industriellen Umgebungen, wie in EN61326-1
definiert, vorgesehen.
In einer industriellen Umgebung können die elektromagnetischen Störungen eventuell
zu Produktfehlfunktionen führen. Um dieses Produkt unter solchen Umständen verwen-
den zu können, muss der Benutzer ggf. angemessene Maßnahmen ergreifen.
Das Produkt ist gemäß EN61010-1 für die folgende Umgebung vorgesehen.
- Überspannungskategorie II
- Verschmutzungsgrad 2
This indicates an imminently hazardous situation which, if
not avoided, will result in death or serious injury. This is to
be limited to the most extreme situations.
This indicates a potentially hazardous situation which, if
not avoided, could result in death or serious injury.
This indicates a potentially hazardous situation which, if
not avoided, may result in minor or moderate injury. It may
also be used to alert against unsafe practices.
Description of what should be done, or what should be followed
Description of what should never be done, or what is prohibited

For Your Safety
VIII
●[FRA] Informations de sécurité
Veillez à lire le présent manuel avant d’utiliser le produit de manière à garantir son utili-
sation correcte et sûre. De même, rangez le manuel dans un lieu sûr de manière à pou-
voir vous y reporter lorsque cela est nécessaire.
Le contenu du présent manuel peut être modifié sans notification préalable.
●Environnement d’installation
Ce produit n'est pas destinés à une utilisation dans des environnements industriels, tels
que définis dans la norme EN61326-1.
Dans un environnement industriel, les interférences électromagnétiques peuvent entraî-
ner un dysfonctionnement du produit. Pour utiliser le produit dans ce type d’environne-
ments, l’utilisateur peut avoir à prendre des mesures appropriées.
Le produit est conçu pour l’environnement suivant, tel que défini dans la norme
EN61010-1.
- Catégorie de surtension II
- Degré de pollution 2
●[ITA] Informazioni sulla sicurezza
Leggere attentamente questo manuale prima di utilizzare il prodotto al fine di utilizzarlo
in modo sicuro e adeguato. Inoltre, conservare in un luogo sicuro il manuale per poterlo
consultare se necessario.
Le contenuti di questo manuale sono soggetti a modifiche senza preavviso.
●Ambiente di installazione
Questo prodotto non è stati progettati per essere utilizzati in ambienti industriali, secondo
la norma EN61326-1.
In un ambiente industriale, le interferenze elettromagnetiche potrebbero causare un mal-
funzionamento del prodotto. Per utilizzare il prodotto in tali ambienti, all'utente potrebbe
essere richiesto di adottare le contromisure necessarie.
Il prodotto è designato per il seguente ambiente, definito nello standard EN61010-1.
- Categoria di sovratensione II
- Livello di inquinamento 2
●[SWE] Säkerhetsinformation
Se till att du läser denna handbok innan du börjar använda produkten för en korrekt och
säker användning av den. Spara sedan handboken på en säker och lättåtkomlig plats så
att du kan konsultera den när så behövs.
Innehållet i denna handbok kan komma att ändras utan föregående meddelande därom.
●Installationsmiljö
Detta produkten är ej avsedda för användning i industriella miljöer enligt riktlinjerna i
EN61326-1.
Om den används i industrimiljöer kan de elektromagnetiska störningarna orsaka tek-
niska fel hos produkten. Om produkten ska användas i sådana miljöer kan användaren
behöva vidta lämpliga åtgärder för att lösa dessa problem.
Produkten är utformad för användning i följande miljöer, i enlighet med SS-EN 61010-1.
- Överspänningskategori II
- Föroreningsgrad 2

For Your Safety
IX
●[SPA] Información de seguridad
Asegúrese de leer este manual antes de utilizar el producto para garantizar un uso
correcto y seguro del mismo. Asimismo, guarde de forma segura el manual para que
esté disponible siempre que sea necesario.
El contenido de este manual están sujetos a cambios sin previo aviso.
●Entorno de instalación
Este producto está diseñado para su uso en entornos industriales, tal y como se define
en EN61326-1.
En un entorno industrial, las interferencias electromagnéticas pueden provocar un fun-
cionamiento incorrecto del producto. Para usar el producto en tales entornos, el usuario
debe tomar las medidas adecuadas.
El producto se ha diseñado para el siguiente entorno, definido en EN61010-1.
- Categoría de sobretensión II
- Nivel de contaminación 2
●[POL] Informacje dotyczące bezpieczeństwa
Przed przystąpieniem do użytkowania tego produktu należy dokładnie zapoznaćsięz
niniejsząinstrukcją, aby zapewniona była prawidłowa i bezpieczna eksploatacja pro-
duktu. Instrukcjęprzechowywaćw bezpiecznym miejscu, aby w razie potrzeby była
zawsze dostępna.
Treść niniejszej instrukcji może ulec zmianie bez wcześniejszego powiadomienia.
●Środowisko instalacji
Ten produkt nie sąprzeznaczone do użytkowania w środowisku przemysłowym, zgodnie
z definicjąokreślonąw normie EN61326-1.
W środowisku przemysłowym zakłócenia elektromagnetyczne mogąpowodowaćniepra-
widłowe działanie produktów. Możliwe, że aby użytkowaćprodukt w takich środowi-
skach, użytkownik będzie musiałpodjąć stosowne środki zaradcze.
Produkt jest przeznaczony do użycia w poniższym środowisku zdefiniowanym w normie
EN61010-1.
- Kategoria przepięciowa II
- Stopieńzanieczyszczenia 2

For Your Safety
X
●[NLD] Veiligheidsinformatie
Lees deze handleiding voordat u dit product gebruikt zodat u het op de juiste manier en
veilig kunt gebruiken. Bewaar de handleiding goed zodat u hem wanneer nodig kunt
raadplegen.
De inhoud van deze handleiding kunnen zonder voorafgaande kennisgeving worden
gewijzigd.
●Installatieomgeving
Dit product is niet bedoeld voor gebruik in een industriële omgeving zoals gedefinieerd in
EN 61326-1.
In een industriële omgeving kan de elektromagnetische interferentie de werking van dit
product storen. Voor gebruik van het product in een dergelijke omgeving moet de gebrui-
ker mogelijk maatregelen treffen om de storing te verhelpen.
Het product is ontworpen voor de volgende omgeving, gedefinieerd in EN 61010-1.
- Overspanningscategorie II
- Vervuilingsgraad 2
●[JPN] 安全情報
ご使用にな る前に、 本書を必ずお読み く だ さ い。 お読みにな っ た後は必要な と き にす ぐ
に取り 出せる よ う に大切に保管し て く だ さ い。
本書に記載 されている内容は予告な く 変更 される場合があ り ます。 あ らか じ めご了承 く
ださい。
●設置環境
本製品は、EN61326-1 で定義 される工業環境で使用する こ と を想定し た製品ではあ り ま
せん。
工業環境においては、 電磁妨害の影響を受ける可能性があ り 、 その場合には使用者が適
切な対策を講ずる こ と が必要 と なる こ と があ り ます。
本製品は、 EN61010-1 で定義される以下の環境用に設計 さ れています。
- 過電圧カ テゴ リ ー II
- 汚染度 2

For Your Safety
XI
●Safety precautions
This section provides precautions for using the product safely and correctly and to
prevent injury and damage. The terms of DANGER, WARNING, and CAUTION indicate
the degree of imminency and hazardous situation. Read the precautions carefully as it
contains important safety messages.
●Instrument and electrode
●Battery
WARNING
Do not use an unspecified AC adapter.
Otherwise, it may heat up or be ignited resulting in a fire or an accident.
Do not disassemble or modify the instrument.
Otherwise, it may heat up or be ignited resulting in a fire or an accident.
CAUTION
Harmful chemicals
The internal solution of DO electrodes is highly potassium hydroxide (KOH).
If it gets into eyes, flush with plenty of water and then consult a doctor. If it
gets into eyes, flush with plenty of water and then consult a doctor.
Harmful chemicals
The internal solution of pH electrode is highly concentrated potassium
chloride (3.33 mol/L KCl). If the internal solution comes in contact with the
skin, wash it off immediately. If it gets into the eyes, flush with plenty of water
and then consult a doctor.
Broken glass
Broken glass may cause injury. The outer tube and tip of an electrode are
made of glass. Handle them with care.
Do not use the RS-232C communication and the AC adapter under wet or
humid conditions. Otherwise, it may cause a fire, electric shock, or
breakage.
WARNING
Keep batteries out of reach of children. If someone accidentally swallows a
battery, consult a doctor immediately.
If alkaline fluid from a battery gets into the eyes, do not rub the eyes, rinse
with clean water immediately and then consult a doctor.
Contact with alkaline fluid could cause blindness.
Do not put batteries in a fire, expose to heat, disassemble or remodel.
Doing so could case fluid leakage, overheating or explosion.

For Your Safety
XII
CAUTION
Do not remove or scratch the external label of the battery.
Doing so could cause injury to hands and fingers.

Product Handling Information
XIII
■Product Handling Information
●Operational precautions (instrument)
・Only use the product including accessories for their intended purpose.
・The function that measuring dissolved oxygen of the instrument is only usable for
measuring under water. Do not use this function for the application except described
above.
・Do not drop, crash, or give any physical impact on the instrument.
・The instrument is made of solvent-resistant materials but that does not mean it is
resistant to all chemicals. Do not dip the instrument in strong acid or alkali solution, or
wipe with such solution.
・If the instrument is dropped into water or gets wet, wipe it using soft cloth. Do not heat
to dry it with a hair-dryer (or the like).
・The instrument has a dust-proof and waterproof structure. Waterproof performance is
following specification: the instrument does not malfunction even when immersed in
water of 1 m depth for 30 minutes.
This does not mean to guarantee non-destructive, trouble-free, dust-proof, and
waterproof performance in all situations. If the instrument is correctly handled
according to the descriptions in this manual, the instrument provides dust-proof and
waterproof performance.
・When replacing the batteries, while connected to the AC adapter, or during the RS-
232C communication, the instrument does not have the dust-proof and waterproof
performance. The dust-proof and waterproof performance is maintained only when the
covers are attached correctly.
・After replacing the batteries, connecting the AC adapter, and using the RS-232C
communication, make sure that the waterproof packing attached to each cover is not
deformed or discolored, or has foreign matter adhering to it. If the waterproof packing
is deformed, discolored or has foreign matter adhering to it, or dust could get inside,
water leaks could occur that could lead to instrument malfunction.
・To disconnect an electrode or AC adapter cable or serial cable, hold the connector and
pull it off. If you pull at the cable, it may cause a breakage.
・The RS-232C communication between the instrument and a personal computer (PC)
may fail because of environmental conditions, such as (radio/electromagnetic) noise.
・Do not replace the batteries, connect the AC adapter, or use the RS-232C
communication in a dusty place or with wet hands. Dust or moisture could get inside
the instrument, possibly causing instrument malfunction.
・Do not use the tip of a nail or an object with a sharp end to press the keys.

Product Handling Information
XIV
・If the power supply is interrupted while measurement data is being saved in the
instrument, the data could be corrupted.
・A NiMH rechargeable battery can be used in this instrument, but the battery used in
the instrument cannot be charged using the AC adapter.
●Operational precautions (battery)
・Do not short circuit a battery.
・Set the + and side of the battery correctly.
・When the battery has run out or the instrument will not be used for a long time, remove
the batteries.
・Of the specified battery types, make sure to use two batteries of the same type.
・Do not use a new battery together with a used battery.
・Do not use a fully charged nickel-metal hydride battery together with a partially
charged battery.
・Do not attempt to charge a non-rechargeable battery.
●Environmental conditions for use and storage
・Temperature: 0°C to 45°C
・Humidity: under 80% in relative humidity and free from condensation
Avoid the following conditions.
・Strong vibration
・Direct sunlight
・Corrosive gas environment
・Close to an air-conditioner
・Direct wind
●Transportation
When transporting the instrument, repackage it in the original package box. Otherwise, it
may cause instrument breakage.
●Disposal
・Standard solution used for the calibration must be under neutralized before the
disposal.
・When disposing of the product, follow the related laws and/or regulations of your
country for disposal of the product.

Manual Information
XV
■Manual Information
●Description in this manual
This interprets the necessary points for correct operation and notifies the important
points for handling the product.
This indicates the part where to refer for information.
This indicates reference information.
●Original language
This is the English translation of an original Japanese document.
Note
Reference
Tip

Contents
XVI
■Preface...................................................................................I
■Check Items..........................................................................II
■Regulations .........................................................................III
■For Your Safety ................................................................. VII
■Product Handling Information ........................................ XIII
■Manual Information...........................................................XV
Part Names and Basic Operation ....................................... 1
■Names of each part..............................................................2
●Instrument ................................................................................... 2
●Identification of manufacturing date......................................... 2
●Display ......................................................................................... 3
●Operation key.............................................................................. 5
■Basic operation....................................................................6
●Changing the operation mode................................................... 6
●Switching the displays ............................................................... 7
●Changing the measurement parameter .................................... 8
●Using the backlight..................................................................... 9
●Entering numeric values .......................................................... 10
Measurement...................................................................... 11
■Preparation.........................................................................12
●Confirmation before starting measurement........................... 12
●Turning ON the instrument ...................................................... 13
●Setting the date and time ......................................................... 15
●Connecting an electrode.......................................................... 16
■pH measurement................................................................17
●Setting the instrument.............................................................. 17
●Performing calibration ............................................................. 20

Contents
XVII
●Performing measurement.........................................................27
■mV, ORP measurement.....................................................28
●Setting the instrument ..............................................................28
●Switching between absolute value and relative value...........29
●Performing measurement.........................................................30
■Dissolved oxygen measurement......................................31
●Setting the instrument ..............................................................31
●Performing calibration..............................................................36
●Performing measurement.........................................................41
Using Various Functions................................................... 43
●Saving measurement data in the internal memory ................44
●Displaying saved data ..............................................................45
●Deleting all saved data .............................................................46
●Displaying the latest calibration and inspection data ...........47
●Deleting calibration data ..........................................................49
●Printing measured values and calibration data .....................50
●Transferring saved data to a PC ..............................................56
●Operating the instrument from an external device ................57
●Using the automatic data save (default: OFF)........................58
●Setting the ID number (default: 000) .......................................60
●Using the calibration interval alarm (default: OFF)................61
●Calibrating temperature sensor...............................................62
●Changing the automatic power off setting (default: OFF).....63
●Performing test printing of the printer unit ............................64
●Resetting to factory default settings.......................................65
Maintenance ....................................................................... 67
●Contact for maintenance ..........................................................67
●Maintenance and storage of the instrument...........................67
●Environmental conditions for storage ....................................67

Contents
XVIII
●Maintenance and storage of the pH electrode ....................... 68
●Maintenance and storage of the ORP electrode .................... 69
●Checking the state of the ORP electrode ............................... 70
●Maintenance and storage of the DO electrode ...................... 71
How to Resolve Errors or Troubles.................................. 73
■When an error message appears .....................................73
●ERR No.0001 Memory error................................................... 73
●ERR No.0002 Empty battery level......................................... 74
●ERR No.0003 Electrode stability error ................................. 74
●ERR No.0004 Asymmetric potential error............................ 74
●ERR No.0005 Electrode sensitivity error (pH) ..................... 75
●ERR No.0005 Electrode sensitivity error (DO)..................... 75
●ERR No.0006 Maximum calibration points exceeded......... 76
●ERR No.0007 Cannot identify standard solution ................ 76
●ERR No.0008 Calibration interval error................................ 76
●ERR No.0009 Printer error..................................................... 77
●ERR No.0010 Memory full...................................................... 77
■Troubleshooting ................................................................78
●The indicated value fluctuates ................................................ 78
●The response is slow ............................................................... 79
●The indicated value does not change/No response .............. 79
●The measured value blinks...................................................... 80
●The temperature display blinks or is fixed at 25°C................ 80
●Repeatability of the measured value is poor ......................... 81
●Nothing appears when the power is turned ON..................... 81
●Swelling of operation key sheet .............................................. 81
●Part of the display is missing .................................................. 82
Appendix............................................................................. 83