AQUAREAD AP-700 Multiparameter Water Quality Probe Instruction Manual

: June 1, 2024
: AQUAREAD

AQUAREAD AP-700 Multiparameter Water Quality Probe

AQUAREAD-AP-700-Multiparameter-Water-Quality-Probe-
PRODUCT

Specifications

Product Name: Multiparameter Water Quality Probe
Document No.: 10401-00870
Revision: W
Date: March 7th, 2024
Manufacturer: Aquaread
Address: Bridge House Northdown Industrial Park, Broadstairs Kent, CT10 3JP ENGLAND
Phone: +44 1843 600 030
Website: www.aquaread.com

Product Usage Instructions

1. Introduction:

Before using the Multiparameter Water Quality Probe, read through this instruction manual carefully to ensure proper usage and understanding of the device.

2. What’s in the Box?

The package should include the Multiparameter Water Quality Probe, necessary cables, connectors, and any additional accessories specified in the product description.

3. Battery Installation and Care:

Follow the guidelines provided in the manual for installing and handling batteries to ensure optimal performance of the device.

4. Overview of the Operating System:

Learn about the initial setup process, language selection, and clock setup to operate the device efficiently.

5. Connecting an AP-2000:

Follow the instructions to properly connect the AP-2000 device for accurate measurements.

6. Taking Measurements:

Instructions on how to take water quality measurements using the Multiparameter Water Quality Probe.

7. Depth Measurement:

For Aquaprobes with a -D suffix only, follow the detailed guidelines for depth measurements, differential depth measurements, and depth calibration.

8. Memory Mode:

Understand how to utilize the memory mode feature for storing and accessing measurement data.

9. Setup & Install:

Guidance on setting up and installing the Multiparameter Water Quality Probe for efficient use.

FAQs

Q: Can this probe detect harmful bacteria or toxins in water?
- A: No, this equipment cannot detect the presence of harmful bacteria or toxins. Always treat suspect water before consumption.
Q: Is the water safe for consumption based on readings from this probe?
- A: Favorable indications from this equipment do not guarantee that water is safe for human or animal consumption. It is recommended to treat suspect water before consumption.

“`

Instruction Manual
for the
Aquaprobe® AP-700, AP-800 & AP-2000
Multiparameter Water Quality Probe
and associated
Aquameter®, Utilities & Accessories
Aquaprobe® firmware Revision 4.07 and Above Aquameter® firmware Revision 6.20 and Above
Document No. 10401-00870
Revision: W
Date: March 7th, 2024
Aquaread® Ltd
Bridge House Northdown Industrial Park
Broadstairs Kent
CT10 3JP ENGLAND
Phone: +44 1843 600 030 www.aquaread.com

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

PROPRIETARY NOTICE
The information disclosed within this document or separately supplied in furtherance of this document includes proprietary rights of Aquaread® Ltd. Neither this document nor the information disclosed herein or of a supplementary nature shall be reproduced or transferred to other documents or used for any other purposes, except as specifically authorised in writing by Aquaread® Ltd. Copyright 2019 Aquaread® Ltd. All rights reserved.

SOFTWARE LICENCE AGREEMENT
By using the Aquameter®, its associated probes and PC based software (AquaLink), you agree to be bound by the terms and conditions of the following software licence agreement. Please read this agreement carefully.

Aquaread® Ltd grants you a limited license to use the software embedded in the devices (the “firmware”) in binary executable form in the normal operation of the products. Title, ownership rights and intellectual property rights in and to the Software remain in Aquaread® Ltd.
You acknowledge that the Software is the property of Aquaread® Ltd and is protected under British copyright laws and international copyright treaties. You further acknowledge that the structure, organisation and code of the Software are valuable trade secrets of Aquaread® Ltd.
You agree not to decompile, dissemble, modify, reverse assemble, reverse engineer or reduce to human readable form the Software or any part thereof or create any derivative works based on the Software.

RECYCLING

Any product bearing this symbol must be handed over to an applicable collection point for the recycling of electrical and electronic equipment. By ensuring this product is disposed of properly, you will prevent possible adverse consequences for the environment which could be caused by inappropriate waste handling.
Note: For return for recycling, please contact Aquaread® Ltd for instructions on how to return end-of-life equipment, accessories, and all auxiliary items for proper disposal.
WARNING
Favourable indications made by this equipment do not guarantee water is safe for human or animal consumption. This equipment can not detect the presence of harmful bacteria or toxins. If in doubt, ALWAYS TREAT SUSPECT WATER PRIOR TO CONSUMPTION.

Limitations of Liability
Aquaread® Ltd and its affiliates specifically disclaim liability for any and all direct, indirect, special, general, incidental, consequential, punitive or exemplary damages including, but not limited to, loss of profits or revenue or anticipated profits or revenue or expenses incurred arising out of the use or inability to use any Aquaread® product, miscalibration, loss of data or product failure, even if Aquaread® Ltd and/or its affiliates has been advised of the possibility of such damages or they are foreseeable or for claims by any third party. Notwithstanding the foregoing, in no event shall Aquaread® Ltd and/or its affiliates aggregate liability arising under or in connection with Aquaread® products, regardless of the number of events, occurrences, or claims giving rise to liability, be in excess of the price paid by the purchaser for the Aquaread® product.

TRADEMARKS
Aquaread®, AquaPlusTM, Aquameter®, Aquaprobe®, AquaLinkTM and RapidCalTM are all trademarks of Aquaread® Ltd.
Microsoft®, Windows® and Excel® are trademarks of Microsoft Corporation
GOOGLETM is a trademark of Google, Inc.

Aquaread® Ltd has no affiliation with Microsoft Corporation or Google, Inc.

www.aquaread.com

Page 2 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

www.aquaread.com

Page 7 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

Introduction

This manual specifically covers the setup, operation, calibration and maintenance of Aquaprobe® models AP-700, AP-800 & AP-2000 running V4.07+ firmware, Aquameter® models running V6.20+ firmware, AquaLink V5.00+ PC software and associated Aquaprobe® accessories. If your Aquaprobe® or Aquameter® are running earlier firmware, the functionality may differ from that shown in this manual. In this case, contact Aquaread for an earlier version of this manual or return your equipment for firmware upgrade.

What’s in the Box

The Aquameter® is supplied with the following:
The Aquameter® unit. Quick release lanyard. Set of 5 AA Alkaline batteries. USB Cable for downloading logged data to a PC. Cross-head screwdriver for fitting the batteries and Probe maintenance. Getting started card for quick reference.
The Aquaprobe® is supplied with the following:
Protective Sleeve End Cap. Calibration bottle filled with RapidCal Solution. Spare calibration / rinse bottle. One mounting nut (pre-fitted). Getting started card for quick reference. 25mL bottle of pH storage solution. Pot of silicone grease. Spare Galvanic DO Membrane Cap (AP-700 & AP-800 only) 25mL bottle of Galvanic DO filling solution (AP-700 & AP-800 only)
If using an AP-2000, you will also need an AP-2000 Extension Cable, which should be purchased separately.
2.1. The Aquameter® and the Environment The Aquameter® is designed to be used outdoors and is rated to IP67, that is to say it is waterproof but it is not designed for submersion. In order to prevent accidental dunking or loss, a lanyard is supplied.
Please note that the socket on the Aquameter® is only waterproof when the associated plug is fitted. Without the plug fitted, water can enter the socket. Damage caused by water ingress through the socket is not covered by your warranty.
You may notice a small hole on the rear of the unit near the top. This is a waterproof vent for the internal barometric sensor. Do not poke anything in this hole! Doing so will cause major damage to the vent’s waterproof membrane and invalidate your warranty.
2.2. The Aquaprobe® and the Environment The Aquaprobe® AP-700 and AP-800 models are designed to be fully submerged in water and are rated to IP68, that is to say, they are rated for continual immersion to a depth of 10 meters, and short term immersion (less than 12 hours) to a depth of 50 meters.

www.aquaread.com

Page 8 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

The Aquaprobe® AP-2000 and AP-2000-D models are designed to be fully submerged in water and are rated to IP68, that is to say, they are rated for continual immersion to a depth of 30 meters, and short term immersion (less than 12 hours) to 100 meters.

2.2.1. Important Notes Regarding Galvanic Corrosion
Galvanic corrosion, sometimes also known as bimetallic corrosion, is an electrochemical process in which one metal corrodes preferentially when it is in contact with a dissimilar metal in the presence of an electrolyte (such as water). A similar galvanic reaction is exploited in batteries to generate an electrical voltage. When installing an Aquaprobe, it is important to recognise and avoid the possibility of creating a situation where galvanic corrosion can occur.

All Aquaprobes are made primarily from hard-galvanised marine grade aluminium. All the time that the aluminium body of the Aquaprobe is insulated from any other type of metal, there should be no problem with corrosion (unless the Probe is placed in strong acids or alkalis, for which it is not designed).

Corrosion problems can occur if the Aquaprobe is mounted near to, and connect to a dissimilar metal, such as stainless steel. Typical examples of this are mounting the Probe inside a steel pipe or suspending it from a steel dock on a steel wire. In these situations, a steel-aluminium battery is created that will generate a voltage of around 0.5V and lead to the corrosion of the metal with the lower potential, in this case the aluminium of the Aquaprobe.

It is important to avoid creating a situation where galvanic corrosion can occur in your installation. The easiest way to do this is by electrically insulating the Aquaprobe from the supporting structure. This can be done by suspending the Aquaprobe on a Mylar or Nylon rope rather than a conductive steel wire.

If the Aquaprobe is to be mounted inside a steel pipe, wrap a good thickness of electrical insulation tape around the top and bottom of the Probe to form `fenders’ in order to prevent the Probe making physical contact with the inside of the pipe. When doing this, ensure that you do not block any of the holes in the Probe’s sleeve, which are essential for water flow and correct operation of the Probe.

If the above techniques are not possible and a metal-to-metal connection is unavoidable, a sacrificial anode must be attached to the Aquaprobe. Sacrificial anodes are manufactured from zinc and are designed to slide onto the threaded connector section of the Aquaprobe and to be held on by the mounting nut. Zinc is much more active than aluminium and will therefore corrode first leaving the Aquaprobe undamaged.

Sacrificial anodes are, as the name suggest, sacrificial, so will need replacing periodically.

Sacrificial anodes are available for all models of Aquaprobes. Please contact Aquaread Ltd for more details.

2.3. Important Information about the Probe Sleeve & Sleeve End Cap
The Aquaprobe® is constructed with an aluminium sleeve surrounding the delicate sensing electrodes. The Sleeve can be easily removed by unscrewing to allow cleaning of the individual electrodes, however, the Probe sleeve forms an integral, working part of the Probe’s measurement system, and MUST be fitted for correct operation.

www.aquaread.com

Page 9 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

Probe sleeves are also specifically matched to the Probe with which they were supplied. If you have more than one Aquaprobe®, be sure not to mix the sleeves up between the Probes. Doing so may seriously affect the performance of the EC electrode.

All Aquaread® Optical Electrodes are incredibly sensitive. For example, the Turbidity electrode is capable of measuring between 0 and 3000NTU with an internal resolution of greater than 0.1NTU. This means that the electrode is able to detect changes in turbidity that are less than 0.003% of the full range! The other optical electrodes have a similar level of sensitivity. It follows, therefore, that in order to provide stable, repeatable readings, the environment in which the measurements are made must be completely stable and repeatable.

For this reason, the Aquaprobe® is constructed with a matt black aluminium sleeve and end cap that enclose the sensing electrodes and provide a closed, constant condition, non reflective measurement chamber.

This is essential for the correct calibration and operation of all types of optical electrodes.

A diagram of the Aquaprobe’s measurement chamber is shown here. Please note, the design of the End Cap may vary depending upon the age and model of your Aquaprobe.

In order to obtain consistent results, the measurement chamber created within the Aquaprobe® must remain physically constant during both calibration and
measurement.

If the optical electrode is calibrated under one set of conditions then used to measure under another set of conditions, the readings will naturally be erroneous, especially at low concentrations.

A perfect example of this is calibrating with the end cap removed then measuring with the end cap fitted (or vice-versa). By changing the physical characteristics of the measurement chamber, you also change the calibration and response of the electrode.

Another particular problem when trying to measure very low concentrations is air in the form of both visible and microscopic bubbles. These act like tiny prisms and can refract and reflect both the excitation light and the return signal being measured.

The photograph to the right was taken in a calibration tube after fresh water was poured in. The bubbles are clearly visible in the light beam.

2.4. Top Tips for successful measurements using optical electrodes Always keep the measurement chamber and electrode lenses clean. Always fit the sleeve and end cap during both calibration and measurement.

www.aquaread.com

Page 10 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

Always allow the readings to settle completely during both calibration and measurement.

Always try to eliminate air bubbles by agitating the Probe after insertion both during calibration and measurement.

Always calibrate and zero the electrode as close to your sample temperature as possible. This is especially important with the Ref-Oil electrode.

Always zero the optical electrodes just prior to use in clean water (bottled still mineral water is ideal) then deploy without disturbing the measurement chamber. This is especially important when using the Turbidity and Ref-Oil electrodes.

2.5. About the Lanyard The lanyard supplied with the Aquameter® may, at first, appear to be a little long. This is intentional. In order to keep the Meter out of the way whilst your hands are full, the lanyard has been made long enough to wear round your neck and over your shoulder so the Meter sits on your hip.
The extra length also allows the meter to be held in a comfortable position in front of you during normal use. In order to prevent you being dragged into the water in the event of the Probe cable becoming snagged, the lanyard includes a quick-release clip.

www.aquaread.com

Page 11 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

Battery Installation and Care

The Aquameter® requires five AA size batteries. To install the batteries, loosen the two screws on the centreline of the rear of the meter and remove the battery compartment lid. Following the battery polarity markings inside the battery compartment, insert five AA cells then replace the compartment lid and tighten the screws.

3.1. Choice of Battery Type
Alkaline or rechargeable batteries may be used, but never mix battery types in the meter. If you choose to use rechargeable batteries, we recommend Energizer 2500mAh (or greater) Nickel-Metal Hydride cells, which are widely available. If the Meter is to be out of use for a long period, remove the batteries to prevent damage due to possible leakage.

3.2. Battery Life
A set of fresh alkaline cells will give over 20 hours use in the AM-200 GPS Aquameter®. A fully charged set of 2500mAh NiMH cells will give up to 40 hours use in the AM-200 GPS Aquameter®. Please be aware however that alkaline battery capacities are extremely temperature dependant. The figures quoted throughout this manual for battery life assume a temperature of 21°C. Battery life can be significantly shorter (by up to 50%) at lower temperatures.

3.3. Battery Charging
During the charging process, batteries generate heat and vent gasses, and must never be charged inside a sealed unit. Because the Aquameter® is a sealed unit, we do not allow charging in-situ. Batteries must be removed and charged with a suitable battery charger outside the Meter. We recommend the use of one of the Energizer range of NiMH chargers.

3.4. Battery Condition Icon
On all the main Aquameter® screens, a battery condition icon is displayed in the top left corner. The icon shows full when the batteries are fresh, and gradually empties as the batteries are used. When the batteries need replacing, the empty battery icon will flash on and off. If you ignore this, the Meter will automatically switch itself off when the battery voltage becomes too low for reliable operation.

When using rechargeable batteries, the battery icon will not show completely full, even with freshly charged cells. This is due to the fact that rechargeable batteries are only rated at 1.2V per cell compared to 1.5V per cell for alkaline batteries. This indication does not affect battery life. The icon will simply sit at the ¾ full mark for a longer period of time.

3.5. Battery Saver Functions
The Aquameter® is designed to switch off automatically if you do not touch any of the keys for 30 minutes. The only exception to this is if you have activated the Automatic Data Logging feature. In this case, the Meter will continue to operate until either the memory is full or the batteries go flat.

The display on the Aquameter® incorporates a white backlight to improve visibility in lowlight conditions. As on a mobile phone, the backlight switches on each time a key is pressed, and stays on at full brightness for 15 seconds. After 15 seconds, the backlight will fade to half brightness. After a further 15 seconds the backlight will switch off.

During normal operation, if you want to activate the backlight without changing the Meter function, simply press the ESC key.

www.aquaread.com

Page 12 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

Overview of the Operating System

The operating firmware in the Aquameter® has been designed for simple, intuitive use. Similarly, a great deal of development work has been put into simplifying and automating the calibration procedures in the Aquameter® in order to allow normal field operatives (as opposed to trained lab technicians) to achieve quick and accurate results.

If you are used to operating a mobile phone or programming audio/visual equipment using a remote control, you should feel at home with the familiar up/down left/right arrow shaped navigation keys and central OK key.

The tree structure behind the MENU key should also be very familiar. Each item on the menu leads to a sub menu and then either onto further menus or final choices. Each branch of the menu system is navigated using the arrow keys. At each point, selections can be made by either pressing the OK key or the right arrow key.

To reverse along a branch of the menu system, use the ESC (escape) key or left arrow key. After a short time, you should be able to navigate around the entire menu system at speed using just the four arrow keys. If, at any time, you leave the Meter in one of the sub-menu screens, it will automatically back out to the main operating screen after 15 seconds.

4.1. Initial Switch On, Language and Clock Setup
To switch the meter on or off, briefly press the red key. Do not hold it down. The meter contains a clock and is capable of operating in several different languages. When switching on for the first time, you must select an operating language and set the clock. The first screen you will see is the Language Selection Screen.

English Italiano Francais Portugues Deutsch Malaysia Espanol Indonesia

To select a language, move the cursor around the list using the arrow keys. To enter your selection, press the OK key or the right arrow key.
The next screen to be displayed is the Time & Date Setting Screen.

Time & Date Time:15:46:37
Date:15/Jun/17

To set the time and date, use the arrow keys to move the cursor around the screen. Use the up and down arrow keys to adjust values. When the time and date are correct, press the OK key. Don’t worry if you make a mistake first time round. You can easily get back to these screens later through the MENU key.

www.aquaread.com

Page 13 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

Connecting an AP-2000

The AP-2000 is designed to connect to the Aquameter® using an AP-2000 Extension Cable. The cable is built-in on the AP-700 & AP-800 models. The AP-2000 Extension Cable features high-pressure metal connectors, which incorporate several O-ring seals at the Probe end. Prior to first connection, the seals must be lubricated using the silicone grease supplied. Apply a generous smear of grease to the O-rings where indicated above. Be careful not to get any grease inside the connector near the gold contacts. A small smear of grease should also be applied to the thread on the Probe to allow easy tightening of the collar.
To connect the Extension Cable to the AP-2000, align the coloured dot on the AP-2000 with the Aquaread® logo on the plug body, then press the plug into the socket and tighten the retaining collar fully. DO NOT TWIST THE CONNECTOR BODY WITH RESPECT TO THE PROBE. Once the AP-2000 has been connected to the Extension Cable, the Aquameter® can be connected.
5.1. Connecting the Aquameter® Always ensure the Aquameter® is switched off prior to connecting or disconnecting an Aquaprobe®. Align the Aquaread® logo on the plug body with the red on/off switch on the Aquameter®, then press the plug into the socket and tighten the retaining collar.
Once the Aquaprobe® is connected to the Aquameter®, switch the Meter on by briefly pressing the red on/off switch. The Aquameter® should detect the Probe and automatically start displaying readings.

Taking Measurements

The Aquaprobe® includes a pH/ORP electrode, which is kept moist by a storage cap. Remove the storage cap by pulling the red lanyard marked `Remove Before Use / Replace After Use’ straight down. Do not use a twisting motion to remove or replace the cap as this can unscrew the electrode from the Probe body. Rinse any salty deposits from the pH/ORP electrode with fresh water.
Fit the protective Sleeve End Cap into the end of the Probe sleeve. Switch the Aquameter ® on and immerse the Aquaprobe® in the sample water, making sure that the water level covers the minimum immersion depth groove halfway up the Probe sleeve.
TIP: Occasional application of a smear of silicone grease or similar lubricant to the protective Sleeve End Cap O ring and the inside rim of the Probe sleeve will make fitting and removal of the Cap easier.
If the Aquaprobe® is connected correctly, the meter will read the Probe’s serial number and model number, then will automatically configure itself to display only those readings the current Aquaprobe® is capable of taking. Initial Probe readings will be displayed on the meter’s screen along with the current GPS status. The initial data screen for the GPS Aquameter® in conjunction with the Aquaprobe® is shown below.

TEMP:018.5°C

ORP:0415.2 mV

pH:06.48

GPS:Acquiring

www.aquaread.com

Page 14 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

Left/right arrows at the bottom corners of the screen indicate further data screens are available. To access these screens, simply press either the left or right arrow keys. Any value that is out of range or unavailable will be displayed as dashes. The other four screens available with the standard AM-200/AP-2000-D combination are shown below.

DO:098.7%

EC:6541µS/cm

TDS:3271mg/L

GPS:3D Pos

SAL:03.57 PSU

SSG:01.3t

GPS:3D Pos

BARO:1013mb

DEPTH:01.75m

Hit [OK] to zero

GPS:3D Pos

Lat:N51 °21.498 Long:E001°24.323 Alt:00050M 1013mb
Sats in use:09

6.1. What Does It All Mean?
The screens above show the full default range of readings for the AM-200/AP-2000-D combination. If you are using a different Meter/Probe combination, you may have fewer screens to choose from and the readings may appear in a different order to facilitate logical screen layouts. If an asterisk (*) character is flashing just below the battery symbol, this indicates that Auto Data Logging is switched on. See Automatic Data Logging in section 8.

The table below explains the readings and indicates which to expect with each Meter/Probe combination.

Prefix TEMP
pH ORP GPS DO EC TDS SAL SSG BARO DEPTH Lat Long Alt

Meaning Probe Temperature
pH (Acidity/Alkalinity) Oxidation Reduction Potential GPS Status Dissolved Oxygen Electrical Conductivity Total Dissolved Solids Salinity Sea Water Specific Gravity Barometric Pressure Depth above / below zero datum Latitude Longitude Altitude above Sea Level

Units
C or F pH or pHmV mV See section 6.5 %Sat & mg/L µS/cm or mS/cm mg/L or g/l PSU or ppt t mb or mmHg Meters / Feet Degrees & Mins Degrees & Mins Meters or Feet

Available On All Probe Types
All Probe Types All Probe Types AM-200 + All Probe Types All Probe Types All Probe Types All Probe Types All Probe Types All Probe Types AM-200 + All Probe Types – D models only AM-200 + All Probe Types AM-200 + All Probe Types AM-200

All Probe Types

Note: the Depth page is not displayed with the standard Aquaprobe®. In this case,

www.aquaread.com

Page 15 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

barometric pressure is displayed after the altitude (Alt) at the end of line 3 on the position and altitude screen, with no prefix (as shown [1013mb] on the above screen example).

Items in the Units column marked with an asterisk (*) can be selected as alternative units of measurement in the Settings Menu (see section 9 Setting Units of Measurement). Items in the Units column marked with a dagger () are auto-ranging, i.e. when the values become too large to display, the units of measurement automatically re-scale.

The EC field can be replaced by its reciprocal value, RES (Resistivity), if selected in the Settings Menu. If selected, readings will be displayed in either cm or Kcm, depending on the value. See section 9 Setting Units of Measurement for more details.

6.2. Trend Indication
To the right of each reading, (except position, BARO and Depth), a trend indication is given. This consists of either an upwards facing arrow (which indicates the numeric value of the reading is rising), a downwards facing arrow (which indicates the numeric value of the reading is falling) or a two- headed arrow, which indicates a stable reading. Readings are judged to be stable when the variation over a ten second period drops below 1%.

6.3. Global Stability Indication
In addition to the individual trend indications, there is a global stability indication, which is displayed when all readings are stable. This takes the form of a flashing double headed arrow which is displayed at the start of the third line of the display.

When taking a set of readings, gently stir the Probe, or raise and lower it in the sample (if there is no natural water flow) until the global stability icon appears. The initial display of the global stability icon will be accompanied by a double beep. When this occurs, all values are stable and ready for reading or saving.

6.4. Temperature Compensation
The electrochemical properties of all solutions change with the solution’s temperature. In addition, the response of electrochemical measuring electrodes change with temperature. It is a fundamental, practical requirement in the field of water quality monitoring that test measurements taken at different temperatures can be compared.

In order to facilitate this, the Aquaprobe® automatically applies corrections for temperature wherever required.

During three point calibration of the ISE electrodes, the variation in response of the electrodes due to temperature is automatically calculated. During measurement, the variation in response of the electrodes due to temperature is automatically compensated for.

During calibration of the EC electrode, the variation in the calibration buffer solution due to temperature is automatically corrected for. During measurement of EC, the readings can be
displayed without any temperature correction, corrected to 20C, or corrected to 25C. See section 9 Setting Units of Measurement for more details.

During calibration of the DO electrode, variations due to temperature and air pressure are automatically compensated for. During the measurement of DO, temperature, air pressure and salinity are automatically compensated for.

www.aquaread.com

Page 16 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

During calibration of the ORP electrode, the variation in the calibration buffer solution due to temperature is automatically corrected for. During measurement of ORP however, temperature corrections are not applied as the correction factors are system and chemical dependent and are not easily determined.
ORP potential measurements are mostly made to follow reactions rather than for their own sake. The completion of an ORP reaction is normally accompanied by a sharp change in the ORP millivolts reading. This change is usually much larger than the errors induced by temperature side effects.
During calibration of the optical electrodes, variations in the calibration solutions due to temperature are automatically compensated for. During the measurement, temperature is automatically compensated for.
During calibration of the pH electrode, the small variation in the calibration buffer solutions due to temperature is not compensated for due to the differences in thermal coefficient between various buffer manufacturers. For this reason, the three pH points should be calibrated as close to the buffer manufacturer’s specified temperature as possible (usually 20ºC or 25ºC) although a variation of up to +/-10ºC makes very little difference in reality.
During pH measurement, temperature variation is automatically compensated for.
6.5. GPS Reception The GPS version of the Aquameter® (AM-200) contains a built-in GPS/GLONAS receiver and antenna. The antenna is situated at the top of the case, just behind the Aquaread® Logo. For optimum signal reception, the antenna must be able to `see’ a reasonably large amount of the sky. The GPS receiver will not work indoors or when shielded from the sky by any solid structure.
After switch-on, the GPS receiver will automatically start to search for satellites. During this phase, the message GPS:Acquiring will be shown on the bottom line of all the screens. As soon as three satellites are acquired, two dimensional position (no altitude) will be calculated and the message GPS:2D POS will be shown on the bottom line of the screens.

Once a fourth satellite is acquired, altitude will be calculated and GPS:3D POS will be shown on the bottom line of the screens. With a good view of the sky, position should be calculated within ninety seconds of switch-on. To see your geographic position and the number of satellites in use, use the left or right arrow keys to scroll to the Position page.
If you switch the meter on indoors, then carry it outside after several minutes, there may be a considerable delay in acquiring satellites. In this case, switch the meter off, then back on again to reset the acquisition process.

www.aquaread.com

Page 17 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

Depth Measurement

(Aquaprobes with a – D suffix only) Depth is measured in the Aquaprobe® by a pressure sensor mounted inside the body of the probe.

Depth is calculated by subtracting the barometric pressure being measured in the Aquameter® from the water pressure being measured in the Aquaprobe®. The pressure differential, once corrected for temperature and salinity (water density), is directly proportional to depth.
The depth measurement system uses the EC sensor to detect when the probe has been placed in water. All the time the probe is measuring an EC of zero, the depth will read zero. As soon as an EC value is detected, the meter will start to calculate depth. For this reason, it is important to ensure the Probe is connected to the Meter and switched on prior to submerging the probe in water.
7.1. Taking Depth Measurements Connect the Probe to the Meter and switch on prior to submerging the probe in water. Select the Baro/Depth screen as illustrated below. The depth should be reading zero.

BARO:1013mb

DEPTH:00.00m

Hit [OK] to zero

GPS:3D Pos

If the depth is not reading zero (this is possible if the probe is wet and a low EC reading is registering), press the OK key. You will be asked to confirm by pressing OK again.

Slowly lower the probe into the water. As soon as the depth value starts to register, you can lower the probe more quickly.

7.2. Differential Depth Measurement
If you want to measure changes in depth, it may be more convenient to zero the depth measurement once the probe has been submerged.

To do this, press the OK key whilst displaying depth, then confirm. The unit will now read positive or negative changes in depth from the current depth (zero datum).

If the values are positive, the water level has increased from the zero datum. If the values are negative, the water level has decreased.

Using the Automatic Data Logging feature detailed in the following section, it is possible to monitor water levels over a period of time for later recall.

7.3. Depth Calibration
The depth sensor is automatically re-zeroed each time the DO 100% point is calibrated in free air. The depth sensor is factory calibrated at two temperatures and two pressures and vary rarely needs to be recalibrated during the lifetime of the Probe. If two point depth calibration is required, it must be done using an AP-PC KIT and associated AquaCal PC Software. Full depth calibration can not be performed using an Aquameter®.

www.aquaread.com

Page 18 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

Memory Mode

8.1. Manually Saving Readings When you are happy that the readings are stable (see section 6.3: Global Stability Indication), press the M+ key to snapshot the readings along with the time, date, GLP (calibration) data and position (GPS models only).
As each reading is saved, a numeric memory location `Tag’ will be briefly displayed which you can note down. This Tag can be used to identify readings at a later date, both on the Aquameter® and when using AquaLink software.
8.2. Recalling and Viewing Saved Readings To recall your readings, press the MR key. On entering Memory Recall mode, the most recent Tag and set of readings are displayed first along with the date and time the readings were taken shown on the bottom line of the screen.
M TEMP:012.5°C M ORP:0415.2mV pH:08.21
02/Apr/17 15:04:01

During Memory Recall, an `M’ is flashed in the top left and right corners of the screen alternatively with an up/down arrow and a left/right arrow. This is to indicate that the Meter is in Memory Recall mode and that other screens can be accessed using the arrow keys.
To see earlier readings, press the up arrow key. Just before each set of readings is displayed, the Tag will be briefly displayed. To view all the parameters within one set of readings, use the left/right arrow keys as described earlier. To exit Memory Recall mode, press the ESC key. If no key is pressed for 30 seconds, Memory Recall mode will be automatically cancelled.
8.3. Recalling GLP Data Each time a set of readings is added to memory, the date of the last successful calibration of each electrode is also appended. This is called GLP (Good Laboratory Practice) Data. In addition to the date of the last successful EC calibration, the Calibration Standard value at which the EC was calibrated is also displayed (see section 15.: EC / Temperature Electrode Calibration and Maintenance for further details).
To view the last successful calibration date for each electrode for any particular stored reading, enter Memory Recall mode, scroll to the reading you are interested in using the up/down keys, then press the MENU key. The screen below will be displayed.
GLP DATA >pH/REDOX(ORP)
DO/EC Aux Electrodes

Using the up/down keys, select the electrode you are interested in, then press either the OK key or the right arrow key. If, for instance, you selected pH/REDOX(ORP), the screen below would be displayed.

www.aquaread.com

Page 19 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

PH 7.00 [31/Jan/17] PH 4.01 [07/Feb/17] PH 10.0 [07/Feb/17] ORP+250 [09/Feb/17] This tells you that the last successful calibration, prior to the recorded reading being taken, was January 31st for the pH 7.00 point, February 7th for the pH 4.01 & pH 10 points and February 9th for ORP. If the date field is dashed (==/===/==), this means the electrode was either not fitted or had never been calibrated.
Pushing the left or right arrow keys will toggle this screen with the calibration report screen.
PH7 Offset:+01.2mV PH4 Slope:56.8mV/pH PH10 Slope:56.3mV/pH ORP Offset:-02.6mV
The calibration report screen displays the calibration report values from the last calibration.
To exit this screen press the ESC key.

8.4. Clearing the Memory The memory within the Aquameter® is capable of storing 10,000 full sets of readings.
To clear the entire memory, switch the Meter off, hold down the M+ key, then switch the Meter back on. A screen will be displayed asking you to confirm your request. Press OK to clear the memory or ESC to cancel and return to normal operation.

8.5. Automatic Data Logging If you want to save readings on a regular basis, in order, say, to check water quality at a certain location over a period of time, you can set the Meter to record readings automatically.
Readings can be logged for short periods with the Meter permanently displaying readings, or for much longer periods in a Low Power Mode, where the Meter switches itself off between readings in order to extent the battery life.
To activate Automatic Logging, press the MENU key. The Main Menu screen will be displayed. Please note, the first item on the menu, ‘Clean Probe’, will only be active if an Aquaprobe® AP-7000 (which has an automatic cleaning system) is connected.

Clean Probe Auto Data Logging Calibration Setup & Install

Select Auto Data Logging by pressing the down arrow key then the right arrow key or the OK key. The Auto Data Logging screen will be displayed.

www.aquaread.com

Page 20 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

Auto Data Logging
Interval:10 Mins Status:OFF
Using the arrow keys to navigate, set the desired logging interval anywhere between 1 and 90 minutes.
To select Sub-Minute Logging Mode, move the cursor right again to the word ‘Mins’, then use the up/down arrow keys to toggle the setting to ‘Secs’. Now the logging interval can be set anywhere between 2 and 90 seconds.
To select permanent display logging mode, set the Status to ON. To select Low Power logging mode, set the Status to LOW POWER. Low Power mode is not available in SubMinute Logging Mode.
To activate the selected logging mode, press the OK key then revert back to the normal operation screen from the Main Menu by pressing the left arrow key.
To indicate that Auto Data Logging is switched on, an asterisk (*) character will flash on and off just below the battery symbol on all the main reading screens.
If permanent display logging mode was selected (Status set to ON), the Meter will record a full set of data automatically at the set rate until either the memory is full or the batteries go flat.
If Low Power Logging Mode was selected (Status set to LOW POWER), the Meter will switch itself off 30 seconds after your last key-press. Thereafter it will switch back on at the set rate, stay on for 30 seconds, log the data, then switch back off again. This will be repeated until either the memory is full or the batteries go flat.
If you press any key while the Meter is off between readings in low power mode, the Meter will switch back on. If no further key is pressed, the Meter will switch back off again after 30 seconds and resume Low Power Mode.
You can cancel Auto Data Logging at any time by going back into the screen above and setting the Status to OFF. Auto Data Logging will also be cancelled if you switch the Meter off manually.

www.aquaread.com

Page 21 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

8.6. Battery and Memory Duration in Low Power Logging Mode Low Power Logging Mode is specifically designed for long term data logging. In order to estimate battery life and memory usage, the following table can be used.
The battery life figures quoted below are based on fresh, good quality alkaline batteries at a Meter temperature of 21°C or over. Colder Meter temperatures will drastically reduce the battery life. For example, at 5°C, the battery life will be approximately half that quoted.

Logging Rate 90 mins 60 mins 45 mins 30 mins 15 mins 5 mins 1 min

Battery Life (at 21°C) 38 Days 36 Days 34 Days 30 Days 20 Days 10 Days 2 Days

Memory Duration* 625 Days 416 Days 312 Days 208 Days 104 Days 34 Days 6.9 Days

So, it can be seen that although the Meter has a maximum data capacity of 625 days, for logging rates above 15 minutes, fresh batteries would need to be fitted every 30 days or so in order to make use of the Meter’s full memory capacity.

Conversely, a logging rate of 2 seconds will fill the Meter’s memory on a single set of batteries (at 21°C or greater).

Useful Tip: If you want GPS data logged in association with your other data, ensure the Meter is positioned face up with a clear view of the sky.

8.7. Important Information About Memory Mode
When data is saved in the Meter, it is compressed in raw Probe format. In other words, the same way that it came up from the Probe. When you recall the data in Memory Recall mode, the data is decompressed, then processed for display.

The advantage of this is that the readings will always appear in the current Meter configuration. For example, if you spent a day taking readings with the Meter set to read EC corrected to 25°C, then when you got back you really want to see EC corrected to 20°C or even raw EC, you can do this by simply changing the Meter settings (see section 9 Setting Units of Measurement).

The stored data can be displayed any way you want on recall. You are not limited to viewing the data in the same way it was logged. This is a major advantage and allows you to actually store and recall far more parameters than can be displayed at any one time.

The same rules apply when data is output to a PC running AquaLink Software via the USB cable. The data that is output is always as per the Meter’s current configuration. You can output the data as many times as you like in various Meter configurations.

www.aquaread.com

Page 22 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

Setup & Install

To alter the way the Aquameter® displays readings, press the MENU key to get to the Main Menu, then choose Setup & Install. The Settings Menu will be displayed. Please note, the ‘Socket Assignment’ option on this screen is only accessible when a Probe is connected.

Time & Date Units Language Socket Assignment

9.1. Setting Units of Measurement
From this screen choose Units. The Units Menu will be displayed. Remember, you can use just the arrow keys to navigate through the branches of the menus. You don’t need to press OK or ESC at each level.

Units Menu EC/TDS
TEMP/pH/SAL BARO/Alt & Depth

At the Units Menu, you have a choice of which units you want to adjust. Choose the first line if you want to adjust Electrical Conductivity or TDS. Choose line 2 if you want to adjust Temperature, pH or Salinity. Finally, line 3 will give access to Barometric Pressure, Altitude and Depth settings.
Moving the cursor right onto the first line will display the following screen.

Units EC:Ref 25°C
TDS Fact:0.65

The first option on this screen allows you to choose how the Meter displays Electrical Conductivity. There are four options. EC can be displayed as Absolute EC’ without any temperature correction [ABS EC], asSpecific EC’ referenced to 20C [Ref 20C], as `Specific EC’ referenced to 25C [Ref 25C] or as a reciprocal of Absolute EC, which is Absolute Resistivity [ABS RES].
Finally, this screen allows you to set the factor that the Meter uses to calculate Total Dissolved Solids from Specific EC. This is the TDS Fact: (TDS = EC x TDS Fact) and can be set anywhere between 0.00 and 1.00. Default value is 0.65.

www.aquaread.com

Page 23 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

Selecting the second line of the Units Menu will display the following screen.

Units TEMP:°C
pH:pH SAL:PSU

The first option on this screen allows you to change the temperature display between C and F.
The second option allows you to change the pH display between plain pH and pHmV. Plain pH displays normal, temperature compensated pH values in the range 0 – 14.
pHmV displays the actual voltage being generated by the pH electrode in +/- millivolts (mV) over a range of +/- 625mV. This is not temperature compensated.
The last option on this screen allows you to choose between displaying salinity in Practical Salinity Units (PSU), or parts per thousand (ppt), which is the same as grams per litre.
Selecting the third line of the Units Menu will display the following screen.
Units BARO:mb
ALT:Metres

The first line allows you to choose between displaying Barometric pressure in millibars (mb) or in mm of mercury (mmHg).

The second line allows you to choose between displaying altitude and depth in metres (M) or feet (F). Whatever units ALT is set to, DEPTH (-D models only) will follow. Altitude is displayed with respect to mean sea level.
Depth is displayed with respect to the depth zero datum, which can be the water surface or any point at which the depth has been zeroed. See section 7: Differential Depth Measurement for further details.
9.2. AUX Socket Assignment (not applicable to the AP-700) The AP-800 features one, and the AP-2000 features two AUX (axillary) sockets into which additional electrodes may be fitted. AUX socket 1 can be fitted with either AP-2000 Optical electrodes or AP-5000/7000 type ISE (Ion Specific) electrodes. AUX socket 2 can be fitted with AP-2000 type ISE electrodes only.
When an electrode has been fitted to an AUX socket (see appendix 3 for fitting instructions), the socket must be assigned to the specific electrode type.
The Socket Assignment option is only available if the Aquameter® is connected to a Probe. This is because the assignment data is held in the Aquaprobe®, not in the Aquameter®.

When the Socket Assignment option has been selected, the following screen will be displayed.

www.aquaread.com

Page 24 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

The numbers 1 6 represent the AUX socket numbers. Only socket 1 is available on the AP-800 and sockets 1 and 2 on the AP-2000. Unavailable sockets are shown as N/A. The additional sockets are available on larger Probes.

SOCKET ASSIGNMENTS 1:EMPTY l 4:N/A
2:EMPTY l 5:N/A 3:N/A l 6:N/A

Using the up and down arrow keys, select the AUX socket you wish to assign then move the cursor to the right by pressing the right arrow key. When the cursor has moved to the right of the AUX socket number, use the up and down arrow keys to select the appropriate electrode type.

The tables below show the available electrode options and the selection that should be made on this screen:

AP-2000/5000 type Optical Electrodes (AUX1 only)

Electrode Part No.

Function

2000-TURB

Turbidity

2000-CPHYLL

Chlorophyll

2000-BGA-PC

Phycocyanin (Blue-Green Algae PC)

2000-BGA-PE

Phycoerythrin (Blue-Green Algae PE)

2000-RHOD

Rhodamine WT Dye

2000-FSCEIN

Fluorescein Dye

2000-REFOIL

Refined Oil

2000-CDOM

CDOM/FDOM

Aquameter® Selection TURB Cphl
BGA-PC BGA-PE
Rhod Fcein R-OIL CDOM

AP-5000/7000 type ISE Electrodes (AUX1 only)

Electrode Part No.

Function

7000-AMM

Ammonium/Ammonia

7000-CHL

Chloride

7000-FLU

Fluoride

7000-NIT

Nitrate

7000-CAL

Calcium

Aquameter® Selection NH4 Cl F NO3 Ca2

AP-2000 type ISE Electrodes (AUX2 only)

Electrode Part No.

Function

2000-AMM

Ammonium/Ammonia

2000-CHL

Chloride

2000-FLU

Fluoride

2000-NIT

Nitrate

2000-CAL

Calcium

Aquameter® Selection NH4 Cl F NO3 Ca2

When the desired electrode type is showing, move the cursor back to the left of the socket number then press OK to send the selection to the Aquaprobe®. The socket assignments are stored in the Aquaprobe®. If you press the ESC key whilst in this screen, any changes you have made will not be transferred to the Aquaprobe®. Please note: changing an AUX
Socket assignment will clear all the calibration data for that socket.

If you subsequently remove an electrode, be sure to set the socket assignment back to EMPTY.

www.aquaread.com

Page 25 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

RapidCal Calibration Method

10.1. About Calibration Calibration is a very important part of successful water quality measurement and should be carried out regularly as detailed in each separate section of this manual. A great deal of development work has been put into simplifying and automating the calibration procedures in the Aquameter® in order to allow normal field operatives (as opposed to trained lab technicians) to achieve quick and accurate results.
As a general rule, pH and EC should be calibrated as close to 25ºC as possible. Optical electrodes should be calibrated as close to their deployment temperature as possible.
In order to standardise calibration techniques, Aquaread® provide plastic calibration bottles into which the Aquaprobe® can be directly inserted. The Aquaprobe® is designed to be calibrated in these calibration bottles with the Probe Sleeve and Sleeve End Cap fitted.
The Probe Sleeve and Sleeve End Cap form an integral, working part of the Probe’s measurement system, and MUST be fitted during calibration and measurement for correct operation. See section 2.3. Important Information about the Probe Sleeve & Sleeve End Cap for further details.
10.2. Special Notes Concerning ISE Electrodes The high ionic concentration of pH calibration solutions (buffers), including RapidCal, can cause significant offsets in ISE electrodes. ISE calibration solutions other than those for that specific ISE can contain interfering ions, again causing offsets.
These offsets are temporary, but best avoided because they can cause significant errors during both calibration and normal operation.
For this reason all ISE electrodes are supplied with a red rubber sealing cap.
The caps should be fitted to all ISE Electrodes when using pH calibration solutions or other ISE calibration solutions other then that specific for the ISE being calibrated in order to protect the ISE electrodes from the effects of the buffer solution and interfering ions.

10.3. Using RapidCal
RapidCal calibrates EC at 2570µS/cm, the pH7.00 point and the zero point of all optical electrodes (except Turbidity) simultaneously. Ideally, this procedure should be carried out at the beginning of each day the Probe is to be used. In addition, you should check the DO 100% calibration point and zero the Turbidity electrode if fitted. To use RapidCal:

1. Remove the lid from a fresh bottle of RapidCal solution, remove the storage cap from the pH electrode if fitted, wash the Probe in distilled water, ensure the Probe Sleeve and End Cap are fitted, then drop the Probe into the RapidCal solution. Bang the Probe against the bottom of the bottle several times in order to remove any air

www.aquaread.com

Page 26 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual
bubbles that may be clinging to the electrodes.

10401-00870 Rev W

2. When the Probe is inserted, ensure the level of the solution is at least up to the minimum insertion line scribed around the Probe sleeve. If the level is low, the EC electrodes will not be covered and EC will not calibrate properly. If the level is low, top up with fresh RapidCal solution.

3. Switch the Aquameter® on and wait until all readings are completely stable. The longer you can leave the probe to achieve thermal equilibrium before proceeding, the better.

4. Ensure the temperature of the solution is between 5ºC and 40ºC (41ºF 104ºF). The closer to 25ºC the better.

5. Press the MENU key then select Calibration. The following screen will be displayed.

Calibration RapidCal
DO 100% Full Cal

6. Select RapidCal. The screen will change to:

PLEASE WAIT Stabilising
000%

The Meter will wait until all readings are stable, then it will send the RapidCal command to the Probe, where the calibration takes place. During calibration, the Calibrating screen is displayed and the progress counter counts up. If the calibration is successful, the counter will reach 100% and the following screen will be displayed.

Calibrating 100%
Press [OK] When calibration is complete, press OK then ESC to return to normal reading mode.

www.aquaread.com

Page 27 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

Now the DO 100% saturation point should be checked and if necessary, calibrated in damp air.

To Check / Calibrate the 100% DO Saturation Point in Damp Air
1. After calibrating with RapidCaL, remove the Probe from the bottle, wash in fresh water, then shake off ensuring there are no droplets adhering to the DO membrane.

2. Moisten a clean cloth or piece of tissue paper with fresh water and wrap it around the open end of the probe ensuring all the holes are covered. Place the probe on a flat surface. Do not hold the probe, the heat from your hands will warm the probe up and interfere with calibration.

3. Wait until the temperature and DO measurements are completely stable. This is very important. If the DO measurement is 100% +/- 1%, there is no need to recalibrate.

4. If recalibration is needed, refer back to the screen shown in item 5 above and select DO 100%.

5. Wait while the Aquameter® carries out the calibration procedure.

6. When the `Calibrating 100%’ screen (shown above) is displayed, press OK then ESC repeatedly to return to normal reading mode.

Finally, if you have a Turbidity electrode fitted, you should calibrate the zero point now using fresh, still mineral water. Refer to section 16.4.7. Turbidity Zero Point Calibration .

www.aquaread.com

Page 28 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

10.4. Calibration Error Messages
If the Aquameter® detects a problem with either the Aquaprobe® or the calibration solution during the calibration procedure, an error will be indicated. The chart below shows the possible errors and how to correct them.

Error Message

Problem

Action

REPLACE DO Full re-calibration required or Optical DO

CAP

Cap needs replacing

See note below.

BATTERIES Battery Voltage is too low for reliable TOO LOW calibration

Replace the batteries

NO PROBE RESPONSE

The Probe is not responding

Check connections / cycle power

READINGS Readings did not stabilise within the

Top up / replace the RapidCal

UNSTABLE expected period

Allow longer for stabilisation.

OUT OF CAL RANGE

Readings are outside calibration limits (can Top up / check calibration be caused by low level / incorrect calibration solution is correct type. Ensure solution). Or the Probe Sleeve is not fitted the Probe Sleeve is fitted

OUT OF TEMP RANGE

Temperature is outside 5C 40C limit

Warm / cool the RapidCal

You are trying to calibrate an upper

Calibrate the zero point first,

CAL ZERO calibration point on an optical electrode

then without switching the

FIRST

without first calibrating the zero point in the Aquameter off, calibrate the

current calibration session.

upper point.

If the ‘REPLACE DO CAP’ error occurs during Optical DO Zero calibration, this usually

indicates that the DO Cap needs replacing. Perform a full DO calibration first at DO Zero

then at 100% DO. If that does not cure the problem, replace the DO Cap ( see Replacing

the Optical DO Cap in section 14).

If the corrective actions shown above for ‘READINGS UNSTABLE’ or ‘OUT OF CAL RANGE’ errors do not work, thoroughly clean the Probe and try again. If the ‘OUT OF CAL RANGE’ error persists, reset the calibration values to Factory Defaults then try again.

If the ‘OUT OF CAL RANGE’ error persists when calibrating EC, check you are using the correct EC Calibration Standard and that the Probe Sleeve is fitted and tight.

If the ‘OUT OF CAL RANGE’ error persists when calibrating pH, check you are using the correct pH Calibration Standard for the calibration point selected.

If the ‘OUT OF TEMP RANGE’ error persists when carrying out a three point ISE calibration, check your solution temperatures are within the specified limits with respect to each other.

Remember: The Probe sleeve forms an integral, working part of the Probe’s measurement system, and MUST be fitted during calibration and measurement for correct operation. If you try to calibrate the Probe without the sleeve fitted, you may get an error message.

10.5. Resetting to Factory Calibration Defaults

In some cases, if there has been a serious calibration error, the easiest way to rectify the situation is to reset the Probe to its factory defaults. To do this, first bring up the Calibration screen:

www.aquaread.com

Page 29 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

Calibration RapidCal
DO 100% Full Cal

Select Full Cal. This will give you a choice of three electrodes:

Calibration pH/REDOX(ORP)
DO/EC Aux Electrodes

Move the cursor arrow to the electrode you want to reset, then press the MR key. If you select Aux Electrodes, you must press OK first to enter the Aux Electrode selection screen. Once in that screen, select the Aux electrode you want to reset then press MR.
A confirmation screen will be displayed.

Are you sure you want to restore the factory calibration values? [ESC]=NO

If you are sure, press the OK key. If you want to change your mind, press the ESC key. If you press OK, you will see a message that says CAL RESTORED.

Once factory calibration defaults have been restored, you must carry out a full calibration of the electrode in question.

10.6. Calibration Reports
At the conclusion of each successful individual electrode calibration, a single line Calibration Report is displayed. This report contains the raw output of the electrode under calibration, uncorrected for temperature.

These values can be recorded and used to track the performance and ageing of the individual electrodes. Please note however, in order to maximise the value of this feature, all calibrations must be performed at the same temperature otherwise the recorded values will not be comparable over time.

10.7. Calibration Data Storage and Retrieval
The Aquaprobe® contains its own microprocessor and memory. All calibration data, including the GLP data, is stored within the Probe’s memory. When a Probe is connected to a Meter, this data is transferred for display and logging.

This is a major advantage and allows you to use a variety of different Probes with a single Meter, without the need for re-calibration.

In order to recall the calibration data for a certain electrode on the Meter, first select the calibration screen for that electrode. If, for instance, you selected pH/REDOX(ORP), the screen below would be displayed.

www.aquaread.com

Page 30 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

PH 7.00 [31/Jan/17] PH 4.01 [07/Feb/17] PH 10.0 [07/Feb/17] ORP+250 [09/Feb/17] This tells you that the last successful calibration was January 31st for the pH 7.00 point, February 7th for the pH 4.01 & pH 10 points and February 9th for ORP. If the date field is dashed (==/===/==), this means the electrode is either not fitted or has never been calibrated.
Pushing the left or right arrow keys will toggle this screen with the calibration report screen.
PH7 Offset:+01.2mV PH4 Slope:56.8mV/pH PH10 Slope:56.3mV/pH ORP Offset:-02.6mV
The calibration report screen displays the calibration report values from the last calibration.
To exit this screen press the ESC key.

www.aquaread.com

Page 31 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

After Use

The Aquaprobe® should always be cleaned after every use.

It is advisable to clean the Probe after use with the cable attached. This will prevent any water entering the Probe’s socket and will allow any deposits to be removed from the connector collar and shell.
The Sleeve on the Aquaprobe® can be removed by unscrewing to allow cleaning of the individual electrodes. After every use, remove the protective Sleeve End Cap then unscrew the sleeve. With the Sleeve removed, the individual electrodes are very vulnerable, so please handle the Probe with extreme care. If you drop it, it’s going to break!
Rinse the exposed electrodes, the inside of the Sleeve and the Sleeve End Cap with fresh, clean water. Shake the water from inside the Sleeve, then reattach. Dry the outside of the Probe using a soft cloth.
Remember to replace the pH/ORP storage cap after use. Failure to do so will damage the electrode. For more details, see Keeping the Electrodes Moist in section 13.
Never clean the Probe with solvents, alcohol or concentrated acid/alkaline based cleaning products such as Decon 90. These products can strip the anodised finish from the Probe and damage the plastic and rubber components. Damage caused by the use of aggressive cleaning agents or solvents is not covered by your warranty.
Store the Probe without the protective Sleeve End Cap fitted in order to allow free air circulation around the individual electrodes.
TIP: Occasional application of a smear of silicone grease or similar lubricant to the connector O-rings and thread, Sleeve thread, the protective Sleeve End Cap O-ring and the inside rim of the lower Probe Sleeve will make fitting and removal of these parts easier.

www.aquaread.com

Page 32 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

General Probe Maintenance

Other than regular cleaning and calibration, very little in the way of maintenance is needed.

12.1. Identifying The Individual Electrodes The photograph below shows the standard AP-2000 electrodes. On the AP-2000, the DO and EC sensors are incorporated into one electrode.
On the AP-700 and AP-800, the DO and EC sensors are separate electrodes.

Please note: The photograph shows the AP-2000 with Optical DO. The AP-700 and AP-800 models may have either Optical DO or Galvanic DO sensors.

Galvanic DO caps and later model Optical DO caps do not have the red warning label fitted to the DO cap.

www.aquaread.com

Page 33 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

pH/ORP Electrode Calibration and Maintenance

13.1. Recognising the pH/ORP Electrode The combined pH/ORP electrode is easy to recognise because it is the only electrode that is not black. This electrode has a clear, gel filled body.
13.2. Electrode Removal and Replacement The pH/ORP electrode can be unscrewed from the Probe body by rotating it anti-clockwise. When replacing an electrode, apply a little silicone grease or similar lubricant to the thread and O ring, then screw fully in.
Gripping the black collar at the top of the electrode, tighten until the O ring is fully compressed. Do not twist the clear section of the electrode whilst tightening.
Useful Tip: The red lanyard that is attached to the pH/ORP storage cap makes a very useful belt wrench for tightening and loosening the pH/ORP and AUX electrodes.

Slide the lanyard over the electrode and use it to grip the knurled body.
Never immerse an Aquaprobe® with the pH/ORP electrode removed. This will cause serious damage to the electrode socket. This is not covered by your warranty.

13.3. Keeping the Electrodes Moist It is very important that the pH/ORP electrode is kept moist when not in use. This is achieved by always fitting the storage cap, which incorporates a sponge that should be soaked in a special storage solution.
The sponge within the storage cap should be moistened with a few drops of pH Electrode Storage Solution each time it is removed and replaced. If a pH/ORP electrode is inadvertently allowed to dry out, it must be re-hydrated by soaking in storage solution for at least one hour prior to use.
13.4. Calibrating pH pH electrodes should be calibrated fully at least once a week to ensure optimum accuracy. Full calibration involves calibrating at pH 7.00 first, then at pH 4.01 and/or pH 10.00. The Aquaprobe® allows for both two and three point pH calibration. Should you decide to carry out just a two point calibration, the probe will automatically calculate and save a calibration value for the uncalibrated third point in order to maintain the electrode’s linearity over the full range of 0 14.
For best results, calibrate all three points as close to 25C as possible.

www.aquaread.com

Page 34 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

13.5. Special Notes Concerning ISE Electrodes
The high ionic concentration of pH calibration solutions (buffers), including RapidCal, can cause significant offsets in ISE electrodes. ISE calibration solutions other than those for that specific ISE can contain interfering ions, again causing offsets.

These offsets are temporary, but best avoided because they can cause significant errors during both calibration and normal operation.

For this reason all ISE electrodes are supplied with a red rubber sealing cap.

The caps should be fitted to all ISE Electrodes when using pH calibration solutions or other ISE calibration solutions other then that specific for the ISE being calibrated in order to protect the ISE electrodes from the effects of the buffer solution and interfering ions.

13.5.1.

Calibrating the First Point (pH 7.00)

Due to the way in which pH calibration works, the Probe must be calibrated at pH7.00 before calibrating at pH 4.01 or pH 10.00. Never calibrate at pH 4.01 or pH 10.00 before first calibrating at pH7.00.

To calibrate the pH electrode follow these steps:

1. Fill a calibration bottle with fresh pH 7.00 solution or RapidCal, remove the storage cap from the pH electrode, wash the Probe in distilled water, then drop the Probe in all the way.
2. Switch the Aquameter® on and wait until the temperature and pH measurements are completely stable.
3. Ensure the temperature of the solution is between 5ºC and 40ºC (41ºF – 104ºF). 4. Press the MENU key then select Calibration. The following screen will be displayed.

www.aquaread.com

Page 35 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

Calibration RapidCal
DO 100% Full Cal
5. Select Full Cal. The screen will change to:
Calibration pH/REDOX(ORP)
DO/EC Aux Electrodes
6. Select pH/REDOX(ORP). The screen will change to:
pH 7.00?[01/Jan/17] PH 4.01?[01/Jan/17] PH 10.0?[01/Jan/17] ORP+250?[01/Jan/17] The dates shown to the right of the screen are the dates of the last successful calibration.
7. Select pH7.00. The screen will change to:

PLEASE WAIT Stabilising
000%

The Meter will wait until the readings are stable, then it will send the calibration command to the Probe, where the calibration takes place. During calibration, the Calibrating screen is displayed and the progress counter counts up. If the calibration is successful, the counter will reach 100% and the following screen will be displayed.
Offset: -1.2mV Calibrating
100% Press [OK]

The top line displays the voltage offset from zero for the pH electrode in +/-millivolts (mV). If this offset goes beyond +/-25mV at 25°C, the pH electrode should be serviced.
This value is stored in the Probe’s memory and can be recalled at any time. See section 10.7. Calibration Data Storage and Retrieval. Press OK then ESC repeatedly to return to normal reading mode.
Remove the Probe from the calibration bottle, rinse thoroughly in de-ionised water, shake off any excess and dry the outer sleeve with a soft cloth.

www.aquaread.com

Page 36 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

13.5.2.

Calibrating the Second Point

The pH electrode can now be calibrated at either pH 4.01 or pH 10.00. If you intend to calibrate at both pH 4.01 and pH 10.00, both points must be calibrated in the same session, i.e. without turning the power off.

If the power is removed after calibrating just one additional point (pH 4.01 for example), the probe will automatically calculate and save a calibration value for the uncalibrated third point in order to maintain the electrode’s linearity.

To calibrate the second point, fill a calibration bottle with fresh pH 4.01 or pH 10.00 solution and drop the Probe in all the way. Follow the procedure detailed above, but at step 6, select either pH4.01 or pH10.0, dependent upon the solution you are using. Wait while the Meter stabilises and calibrates. When the `Calibrating 100%’ screen is displayed, the calibration report will display the slope for the pH electrode in millivolts (mV) per pH unit. If this slope
goes below 45mV/pH at 25°C, the pH electrode should be serviced. Press OK then press the ESC key repeatedly to get back to the main display.

Remove the Probe from the calibration bottle, rinse thoroughly in fresh water, shake off any excess and dry the outer sleeve with a soft cloth.

13.5.3.

Calibrating the Third Point

Without switching the Aquameter® off or disconnecting the Probe, fill a calibration bottle with

fresh pH 4.01 or pH 10.00 solution and drop the Probe in all the way. Follow the procedure

detailed above, but at step 6, select either pH4.01 or pH10.0 dependent upon the solution

you are using. Wait while the Meter stabilises and calibrates. When the `Calibrating 100%’

screen is displayed, the calibration report will display the slope for the pH electrode in

millivolts (mV) per pH unit. If this slope goes below 45mV/pH at 25°C, the pH electrode should be serviced. Press OK then press the ESC key repeatedly to get back to the main

display.

Remove the Probe from the calibration bottle, rinse thoroughly in fresh water, shake off any excess and dry the outer sleeve with a soft cloth. Dampen the sponge in the storage cap with storage solution and fit it to the pH/ORP electrode. pH calibration is now complete.

13.6. Errors During Calibration
If a problem occurs during calibration, an error message will be displayed. Refer to Calibration Error Messages in section 10 for error message handling.

13.7. pH Electrode Efficiency
If the pH electrode becomes worn or clogged, its efficiency and response time can be reduced. The efficiency of the pH electrode is constantly monitored and in the event of the efficiency dropping below 85%, `ERROR 01′ will be flashed on the bottom line of the display. If this occurs, or if the pH reading response becomes slow, recondition the electrode as described below.

13.8. Servicing the pH Electrode
1. Remove the pH or combined pH/ORP electrode from the Probe body (see Electrode Removal and Replacement).
2. Rinse with methyl alcohol. 3. Replace the electrode. 4. Re-calibrate.

www.aquaread.com

Page 37 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

Never place the entire Aquaprobe® in methyl alcohol, as this will cause irreparable damage to the DO/EC electrode. Damaged caused in this way is not covered by the warranty.

If the methyl alcohol rinse does not restore the electrode, perform the following actions:

1. Remove the electrode from the body again. 2. Soak in 0.1M HCl for 5 minutes. 3. Rinse in de-ionised water. 4. Soak in 0.1M NaOH for 5 minutes. 5. Rinse in de-ionised water. 6. Soak in pH4.01 buffer for 10 minutes.

If the above procedure still does not restore performance, replace the electrode.

13.9. Calibrating ORP
ORP electrodes should be calibrated at least once a month to ensure optimum accuracy. Full calibration involves calibrating at a single point, either +250mV (at 25C) using a +250mV ORP calibration standard such as Reagecon RS250 Redox Standard, or +229mV (at 25C) using a +229mV ORP calibration standard such as Zobell Solution.

For best results, calibrate as close to 25C as possible. The probe will automatically compensate for temperature variation in the calibration solution during calibration.

To calibrate the ORP electrode follow these steps:

1. Fill a calibration bottle with fresh calibration solution, remove the storage cap from the pH/ORP electrode, wash the Probe in distilled water, then drop the Probe in all the way.

2. Switch the Aquameter® on and wait until the temperature and ORP measurements are completely stable.

3. Ensure the temperature of the solution is between 5ºC and 40ºC (41ºF 104ºF).

4. Press the MENU key then select Calibration. The following screen will be displayed.

Calibration RapidCal
DO 100% Full Cal

5. Select Full Cal. The screen will change to:

Calibration pH/REDOX(ORP)
DO/EC Aux Electrodes
www.aquaread.com

Page 38 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual
6. Select pH/REDOX(ORP). The screen will change to:

10401-00870 Rev W

pH 7.00?[01/Jan/17] PH 4.01?[01/Jan/17] PH 10.0?[01/Jan/17] ORP+250?[01/Jan/17] 7. Move the arrow to the bottom line. If you are using 250mV calibration solution press the OK key to continue. If you are using 229mV calibration solution, move the cursor to the right, then use the up/down arrow keys to select +229. When the correct solution has been selected, press OK. The screen will change to:

PLEASE WAIT Stabilising
000%

The Meter will wait until the readings are stable, then it will send the calibration command to the Probe, where the calibration takes place. During calibration, the Calibrating screen is displayed and the progress counter counts up. If the calibration is successful, the counter will reach 100% and the following screen will be displayed.

Offset: 5.5mV Calibrating
100% Press [OK] The Calibration Report on the top line displays the voltage offset between the ORP electrode output and the value of the calibration solution at the calibration temperature in +/-millivolts (mV). During normal operation this offset will be subtracted from the ORP electrode output to give a corrected ORP display.
This value is stored in the Probe’s memory and can be recalled at any time. See section 10.7. Calibration Data Storage and Retrieval. Press OK then ESC repeatedly to return to normal reading mode.
Remove the Probe from the calibration bottle, rinse thoroughly in fresh water, shake off any excess and dry the outer sleeve with a soft cloth. Dampen the sponge in the storage cap with storage solution and fit it to the pH/ORP electrode. ORP calibration is now complete.

www.aquaread.com

Page 39 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

13.10. Converting ORP Readings to the Hydrogen Scale
Electrochemical measurements are ultimately referred to the so-called hydrogen scale, the convention for which is that the electrochemical potential of a hydrogen electrode in contact with hydrogen gas at one atmosphere partial pressure and a solution containing hydrogen ions at unit activity is zero at all temperatures.

The ORP reference electrode used in Aquaread® combination electrodes is a 3MPK1 silver chloride type, and exhibits potentials on the hydrogen scale of:

Temperature 5C 10C 15C 20C 25C 30C 35C 40C

Potential 221 mV 217 mV 214 mV 210 mV 207 mV 203 mV 200 mV 196 mV

Thus, to refer an ORP potential value measured with the Aquaprobe® to the hydrogen scale, the appropriate value above should be added to the measured value.

www.aquaread.com

Page 40 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

DO Electrode Calibration and Maintenance

14.1. Recognising the DO Electrode Type All AP-2000 Aquaprobes are fitted with Optical DO electrodes. The AP-700 and AP-800 may be fitted with either an Optical DO or Galvanic DO electrode. Refer to the photograph on the right to identify your DO electrode type. If your Aquaprobe® features an Optical DO electrode, skip to section 14.6..

14.2. Galvanic DO Electrode The Galvanic DO electrode consists of an electrolyte filled DO sensor cap with a clear, gaspermeable membrane stretched across a silver electrode.
14.3. Precautions During Use In order to achieve accurate Dissolved Oxygen readings with the Galvanic DO electrode, the Probe needs to be either placed in flowing water, or needs to be stirred or raised and lowered continuously to ensure a minimum flow rate of 0.3m/s over the DO Electrode. If there is no water flow across the Probe, the oxygen in the immediate area of the DO Electrode will be consumed and the reading will start to fall.
14.4. Calibrating the Galvanic DO Electrode The DO electrode should be calibrated at the Zero saturation point at least once a month. Before each day’s use, the 100% saturation point should be checked in moist air and recalibrated if necessary. For optimum accuracy, calibrate the DO100% point as near to your sample temperature as possible (within the calibration temperature limits of 5C – 40C).
If you are going to calibrate both the Zero and 100% points at the same time, ALWAYS calibrate the Zero point first, then the 100% point.
14.4.1. Calibrating the DO Zero Point
1. Remove the lid from a 150mL bottle of DO Zero calibration solution, remove the storage cap from the pH electrode if fitted, wash the Probe in distilled water, then drop the Probe in all the way.
2. Switch the Aquameter® on and wait until the DO reading is completely stable. 3. Ensure the temperature of the solution is between 5C and 40C (41F – 104F). 4. Press the MENU key then select Calibration. The following screen will be
displayed. Calibration
RapidCal DO 100% Full Cal

5. Select Full Cal. The screen will change to:

Calibration pH/REDOX(ORP)
DO/EC TURB

6. Select DO/EC. The screen will change to:

www.aquaread.com

Page 41 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual
Calibration DOZero?[01/Jan/17] DO100%?[01/Jan/17] EC2570?[01/Jan/17]

10401-00870 Rev W

The dates shown to the right of the screen are the dates of the last successful calibration. 7. Select DOZero. The screen will change to:

PLEASE WAIT Stabilising
000%

The Meter will wait until the readings are stable, then it will send the calibration command to the Probe, where the calibration takes place. During calibration, the Calibrating screen is displayed and the progress counter counts up. If the calibration is successful, the counter will reach 100% and the following screen will be displayed.

Output:0.4 Calibrating
100% Press [OK]

The Calibration Report on the top line will display the voltage output from the DO cell in millivolts (mV). Please contact Aquaread for current acceptable calibration values.
This value is stored in the Probe’s memory and can be recalled at any time. See section 10.7. Calibration Data Storage and Retrieval. Press OK then ESC repeatedly to return to normal reading mode.
If a problem occurs during calibration, an error message will be displayed. Refer to Calibration Error Messages in section 10.4 for error message handling. If If the ‘OUT OF CAL RANGE’ error persists when calibrating the DO sensor, replace the DO Electrode Membrane Cap.
Remove the Probe from the calibration bottle, rinse thoroughly in fresh water, shake off any excess and dry the outer sleeve with a soft cloth.

14.4.2.

Calibrating the DO 100% Saturation Point in Moist Air

1. Wash the probe thoroughly in fresh water, then shake off ensuring there are no droplets adhering to the DO membrane.

www.aquaread.com

Page 42 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

2. Moisten a clean cloth or piece of tissue paper with fresh water and wrap it around the open end of the probe ensuring all the holes are covered. Place the probe on a flat surface. Do not hold the probe, the heat from your hands will warm the probe up and interfere with calibration.
3. Switch the Aquameter® on and wait until the temperature measurement is completely stable. This is very important.
4. Referring back to the screens shown in item 6 above, select DO100% 5. Wait while the Aquameter® carries out the calibration procedure. 6. When calibration is complete, the Calibration Report will be displayed.

The top line will display the voltage output from the DO cell in millivolts (mV). This value should be over 20.0 (at 25°C). If the value returned is less than 20.0, the DO Cap should be replaced.

These values are not stored in memory so should be noted down in a calibration record book for the probe. If a problem occurs during calibration, an error message will be displayed. Refer to Calibration Error Messages in section 10.4 for error message handling.

14.5. Replacing a Galvanic DO Electrode Membrane Cap
The Galvanic DO electrode membrane is a very thin sheet of special plastic, which is permeable to oxygen. Oxygen molecules pass through this membrane into the Oxygen sensor. The membrane is extremely delicate and is factory fitted into the DO Membrane Cap. To ensure optimum performance, the DO Membrane Cap must be replaced every 1-2 months.

Never touch the plastic membrane as the oils in your skin will block the pores in the membrane and stop it from working correctly.

To replace the DO Membrane Cap, follow these simple steps. 1. Remove the Probe sleeve. 2. Unscrew the DO Cap from the end of the DO electrode by rotating it anti-clockwise. 3. Gently scrape away any soft grey deposits from the zinc shaft of the electrode taking care not to damage the electrode in the process. If the deposits are hard and dry, soak the electrode in DO filling solution until the deposits soften up, then remove them. 4. After removing the deposits, rinse the electrode with DO Electrode Filling Solution. 5. Rinse a new DO Membrane Cap with DO Electrode Filling Solution then tap it out so that it is completely empty. 6. Using the DO Electrode Filling Solution dropper bottle, half fill the DO Membrane Cap. Gently tap the cap to ensure any trapped air bubbles are released. 7. Holding the Probe so that the DO electrode is facing downwards, slowly screw the half-filled DO Membrane Cap back onto the DO electrode then tighten the cap. Do not over-tighten. Finger tight is fine. Some solution will overflow. This is normal. 8. Wash the DO electrode with fresh water then replace the lower Probe sleeve. 9. Wait at least six hours (preferably over-night) to allow any oxygen dissolved in the filling solution to be consumed. 10. Carry out both Zero point and 100% point DO calibration as described earlier.

www.aquaread.com

Page 43 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

NEVER re-install a Galvanic DO Membrane Cap once it has been fully tightened. The membrane will be stretched and will not seal properly over the silver cathode a second time. If the membrane does not create a proper seal over the silver cathode, the DO sensor will not operate correctly and any readings given will be erroneous.

Please note: After a period of use and dependant upon how previous cleaning operations have been performed, the surface of the zinc shaft will become rugged and apparently corroded. This is entirely normal and will not affect the performance of the electrode.

14.6. Optical DO Electrode If your Aquaprobe® is fitted with an Optical DO electrode, the following sections apply. See Appendix 1. The Tech Behind Aquaread’s Optical DO Measurement System for more technical details of the Optical DO measurement system.
Unlike the Galvanic DO electrode, the Optical DO electrode does not consume oxygen during operation so does not require a constant flow of water or stirring.
14.7. Calibrating the Optical DO Electrode The DO electrode should be calibrated at the Zero saturation point at least once a month. Before each day’s use, the 100% saturation point should be checked in moist air and recalibrated if necessary. For optimum accuracy, calibrate the DO100% point as near to your sample temperature as possible (within the calibration temperature limits of 5C – 40C).
If you are going to calibrate both the Zero and 100% points at the same time, ALWAYS calibrate the Zero point first, then the 100% point.

14.8. Calibrating the DO Zero Point 1. Remove the lid from a 150mL bottle of DO Zero calibration solution, remove the storage cap from the pH electrode if fitted, wash the Probe in distilled water, then drop the Probe in all the way. 2. Switch the Aquameter® on and wait until the DO reading is completely stable. 3. Ensure the temperature of the solution is between 5C and 40C (41F – 104F). 4. Press the MENU key then select Calibration. The following screen will be displayed.
Calibration RapidCal
DO 100% Full Cal
5. Select Full Cal. The screen will change to:
Calibration pH/REDOX(ORP)
DO/EC Aux Electrodes
6. Select DO/EC. The screen will change to:

www.aquaread.com

Page 44 of 141

Aquaprobe® AP-700, AP-800 & AP-2000 Instruction Manual

10401-00870 Rev W

Calibration DOZero?[01/Jan/17] DO100%?[01/Jan/17] EC2570?[01/Jan/17] The dates shown to the right of the screen are the dates of the last successful calibration.
7. Select DOZero. The screen will change to:
P