idronaut Ocean Seven 310 User manual

IDRONAUT S.r.l.
Via Monte Amiata, 10 –Brugherio (MB) –ITALY
Tel. [phone] –883832
Fax. [phone]
Email: [email protected]
Web: http://www.idronaut.it

OCEAN SEVEN 310 CTD
Multi-parameter CTD
OPERATOR'S MANUAL
Copyright @ 1982 –2018 Idronaut S.r.l. All rights reserved.
OCEAN SEVEN and Idronaut are registered trademarks of Idronaut S.r.l.
Other products and services mentioned in this document are identified by the trademarks or service marks of their respective companies
or organisations. No part of this publication, or any software included with it, may be reproduced, stored in a retrieval system, or
transmitted in any form or by any means, including photocopying, electronic, mechanical, recording or otherwise, without the prior
written permission of the copyright holder. Idronaut S.r.l. provides this document as is without warranty of any kind either expressed or
implied including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose. Idronaut S.r.l. may
make changes of improvements in the equipment, software, firmware, or specifications described in this document at any time and
without notice. These changes may be incorporated in new releases of this document. This document may contain technical inaccuracies
or typographical errors. Idronaut S.r.l. waives responsibility of any labour, materials, or costs incurred by any person or party as a result
of using this document. Idronaut S.r.l. shall not be liable for any damages (including, but not limited to, consequential, indirect or
incidental, special damages, or loss of profits or data) even if they were foreseeable and Idronaut S.r.l. has been informed of their potential
occurrence arising out of or in connection with this document or its use.
IDRONAUT S.r.l.
Via Monte Amiata, 10 –Brugherio (MB) –ITALY
Tel. [phone] –883832 Fax. [phone]
Email: [email protected] Web: http://www.idronaut.it

IDRONAUT –Brugherio (MB) OCEAN SEVEN 310 CTD 01-2019
IMPORTANT REMARKS
INTERNAL BATTERY REPLACEMENT/RECHARGING
1) To gain access to the battery pack, remove the screws in the probe top cover. However,
before doing this, please ensure to have removed any water droplets around the screw
heads, to prevent them from running down inside the housing.
CTD Top-Cover removal, please follow the instructions in Appendix “A”
2) Rechargeable battery: disconnect the battery pack from the top cover and connect it
to the battery charger.
3) If the probe is not to be used for long periods (some months), remove the internal
battery pack from the probe. This eliminates the possibility of damaging the electronic
circuitry in case of battery leaks because a small amount of energy is drawn from the
internal batteries by the probe electronic circuitry even if OFF. This phenomenon
causes batteries to run down and they may be damaged (leak) in a very long time
SELF-RECORDING USE
➢The CTD internal Real-Time Clock (RTC) keeper is powered by the CTD main battery. If the
battery run-off energy or is disconnected, the RTC loses date & time. It is mandatory to set
up the CTD date & time or/and check that the CTD date & time are correct before starting
a self-recording data acquisition cycle.
➢The CTD is equipped with a rotary magnetic power ON/OFF switch, installed on the top
cover. The CTD is ON when the switching arm is positioned over the red dot marker. Once
the CTD self-recording configuration is completed, the CTD can be switched OFF and then
ON again at the sampling site, when ready for the deployment. This procedure is
indispensable to run self-recording data acquisitions, as described in the dedicated section
of this manual.
VERY IMPORTANT: Allow a 10-second interval between each ON/OFF cycle.
CONDUCTIVITY MEASUREMENT
➢To obtain the best accuracy, the conductivity sensor and therefore the CTD sensor head, must
be immersed in clean seawater or freshwater for at least 15 minutes before measurements.
➢When the conductivity sensor is not in use, it is kept dry. Therefore, when the conductivity
sensor is placed in water, very small bubbles may remain attached to the platinum ring
electrodes (seven). If such a thing happens, the measured value of conductivity will be lower
than the true one. To remove these air bubbles, degrease the inside of the conductivity cell
using cotton buds wetted with the Conductivity Sensor Cleaning Solution or with liquid soap.
Gently rotate the cotton bud against the whole internal surface of the quartz cell. This will
wet the platinum electrodes, thus reducing the surface tension of the cell and considerably
decreasing the risk of trapped air bubbles.
OXYGEN MEASUREMENT
Most polarographic oxygen sensors take 5 to 10 minutes after they have been switched on
to polarize and become stable. To overcome this limitation, the IDRONAUT OS310 has been
fitted with a small internal rechargeable device, to maintain polarization of the oxygen
sensor continuously for about three days. However, if the probe is not used for several days,
the polarization device may become completely discharged. It is recommended that the
probe should be switched ON (and streaming real-time data) for at least few minutes, to

IDRONAUT –Brugherio (MB) OCEAN SEVEN 310 CTD 01-2019
fully recharge the polarization device in a healthy condition before starting the
measurements.
BLUE CAP OPTICAL DISSOLVED OXYGEN SENSOR
A black cap is provided to protect the membrane from light. When the CTD is not used
protect the membrane by installing the black cap.Please, remove the black cap before
calibration and before deploying the CTD in water.
pH MEASUREMENT
The pH and reference sensors should never be allowed to dry out. For short-term storage of
up to one day, the probe’s sensor head can simply be immersed in water. If the probe
remains unused for periods longer than one day, always place the hydrating caps on both
sensors.
The pH sensor cap should be filled with the pH7 Buffer Solution (or simply with clean
water). The reference sensor cap should be filled with the Idronaut Reference Sensor Storage
Solution.
CTD SENSORs RE-CALIBRATION?CHECKING
A dedicated Windows software described at section F.7.3 allows to correctly capture data
from the CTD sensor during a re-calibration procedure or CTD sensors performance
checking cycle. Captured data can be saved in a txt file. The “OceanSevenCalibration”
software is freely distributed with the IDRONAUT ITERM software.
PROBE WASHING
After use, the probe must be always washed with fresh water to remove any salt water
residual or dirtiness.

IDRONAUT –Brugherio (MB) OCEAN SEVEN 310 CTD 01-2019
COPYRIGHT STATEMENT
Copyright IDRONAUT S.r.l.
OCEAN SEVEN and IDRONAUT are registered trademarks of IDRONAUT S.r.l. All rights reserved.
This document may not, in whole or in part, be copied, photocopied, reproduced, translated, or reduced to
any electronic medium or machine-readable form without prior consent in writing from IDRONAUT S.r.l.
ABOUT THIS MANUAL
This manual will serve as a guide to you when you use the OCEAN SEVEN 310 CTD.
❖Use it to understand the purpose of each of the probe components and functions.
❖It will help you to understand the probe behaviour.
❖It will guide you through the probe capabilities.
❖It will serve you as a reference when some problems arise when using the probe.
HOW TO USE THIS MANUAL
The following topics are covered by this manual:
Section 1 A description of the OCEAN SEVEN 310 CTD.
Section 2 Installation and start-up operations.
Section 3 Data acquisition functions and data processing capabilities.
Section 4 Data storage functions.
Section 5 Sensor calibration functions.
Section 6 Service functions (configuration, diagnostics).
Section 7 Probe maintenance.
Section 8 Troubleshooting
Appendix A Internal and external battery pack description.
Appendix B Data Processing Function Priming.
Appendix C OPTIONAL Sensor
Appendix D Advanced configuration
Appendix E Rosette interfacing.
Appendix F IDRONAUT Windows Terminal Emulation Programme.
Appendix G Antifouling device.
Appendix H Wireless “Bluetooth™” –WiFi interface.
Appendix I Submersible connectors and cable care.
Appendix L Sensor cleaning and care.
Appendix M AUV Version
GETTING STARTED
To become familiar with the OCEAN SEVEN 310 CTD capabilities and operation, we suggest reading through
sections 1 and 2. It is necessary to also read sections 3 and 5 and section 7 before starting to deploy the probe.
The remaining sections and appendices could be consulted only when needed. If the probe is supplied with
external sensors, deck unit or the IDRONAUT Portable Reader, useful information can be found in each
dedicated Operator’s Manual.
Operator’s Manuals of all IDRONAUT products and software can be found on the USB-data storage key
included with this product in the “Literature&Manuals\OperatorManual” folder.
NOTATIONAL CONVENTIONS
Throughout this manual, the following conventions are used to distinguish the various elements of the text:
[PROBE COMMANDS] They always appear in uppercase and between [ ] or < > brackets.
Probe messages, user inputs They always appear in italics.
DEFINITION OF TERMS

IDRONAUT –Brugherio (MB) OCEAN SEVEN 310 CTD 01-2019
Throughout this manual, the following terms are used:
Cast As a whole of the data set collected in the same way in a determined
sampling point.
Data set As a whole of configured parameters expressed in physical or
chemical units and acquisition date and time, collected at
programmed sampling interval, (i.e. once per second, once per
depth increment).
Raw data –ADC Counts As a whole set of data acquired by means of the ADC and the
conditioning circuits, from the configured sensors and are
expressed in numeric decimal or hexadecimal format.
Non-verbose mode This term refers to a probe that has been configured to use a
communication protocol (computer oriented) to communicate with
the operator.
Verbose mode This term refers to a probe that has been configured to use the MMI
functions to communicate with the operator.
ON condition This term refers to a fully operative probe, waiting for commands
from the operator or running the requested command.
OFF condition This term refers to a probe electronically switched off. In this state,
the probe draws negligible amount of current from the battery.
MMI This term refers to the set of common rules, which the operator must
follow during the operation of probe in verbose mode.
QAM Quadrature Amplitude Modulation.
IDRONAUT DOCUMENTS PERTAINING TO THE OCEAN SEVEN 310
The following documents are available in the “Literature & Manual” folder on the USB-data storage key
distributed with the OCEAN SEVEN 310 CTD.
❖OCEAN SEVEN Probes Data Transmission Protocol Description
❖IDRONAUT Deck Unit Operator’s & Installation manual
❖REDAS-5 Condensed Manual
❖OCEAN SEVEN Portable Reader Operator’s Manual
SOFTWARE UPDATES AND TECHNICAL SUPPORT
Please visit our website download area for software updates and technical support: http://www.idronaut.it
WARRANTY
The OCEAN SEVEN 310 CTD is covered by a one-year limited warranty that extends to all parts and labour
and covers any malfunction that is due to poor workmanship or due to errors in the manufacturing process.
The warranty does not cover shortcomings that are due to the design, nor does it cover any form of
consequential damage because of errors in the measurements. If there is a problem with your OCEAN SEVEN
310, first try to identify the problem by following the procedure outlined in the troubleshooting section of this
manual. Please contact your representative or IDRONAUT Sr.l. if the problem is identified as a hardware
problem or if you need additional help in identifying the problem. Please make sure to contact IDRONAUT
S.r.l. to obtain the relevant instructions before the OCEAN SEVEN 310 or any module is returned to
IDRONAUT (see cleaning instructions).
For systems under warranty, IDRONAUT S.r.l. will attempt to ship replacement parts before the
malfunctioning part is returned. We encourage you to contact us immediately if a problem is detected and we
will do our best to minimize the downtime. Every effort has been made to ensure the accuracy of this manual.
However, IDRONAUT S.r.l.makes no warranties with respect to this documentation and disclaims any
implied warranties of merchantability and fitness for a particular purpose. IDRONAUT S.r.l.shall not be liable
for any errors or for incidental or consequential damages in connection with the furnishing, performance or
use of this manual or the examples herein. The information in this document is subject to change without
notice.

IDRONAUT –Brugherio (MB) OCEAN SEVEN 310 CTD 01-2019
CLEANING INSTRUCTIONS
Before the returned OCEAN SEVEN 310 can be serviced, equipment exposed to biological, radioactive, or
toxic materials must be cleaned and disinfected. Biological contamination is presumed for any instrument,
probe, or other device that has been used with wastewater. Radioactive contamination is presumed for any
instrument, probe or other device that has been used near any radioactive source. If an OCEAN SEVEN 310
CTD, or other part is returned for service without following the cleaning instructions, and if in our opinion it
represents a potential biological or radioactive hazard, our service personnel reserve the right to withhold
service until appropriate cleaning, decontamination has been completed.
When service is required, either at the user's facility or at IDRONAUT, the following steps must be taken to
insure the safety of our service personnel.
➢In a manner appropriate to each device, decontaminate all exposed surfaces, including any containers.
70% isopropyl alcohol or a solution of 1/4 cup bleach to 1-gallon tap water are suitable for most
disinfecting. Instruments used with wastewater may be disinfected with 5% Lysol if this is more
convenient to the user.
➢The user shall take normal precautions to prevent radioactive contamination and must use
appropriate decontamination procedures should exposure occur. If exposure has occurred, the
customer must certify that decontamination has been accomplished and that no radioactivity is
detectable by survey equipment.
➢Any product being returned to the IDRONAUT S.r.l. laboratory for service or repair should be packed
securely to prevent damage.
➢Cleaning must be completed on any product before returning it to IDRONAUT S.r.l.
DISPOSAL OF WASTE EQUIPMENT BY USERS IN THE EUROPEAN UNION
The recycling bin symbol on the product or on its packaging indicates that this product must not be disposed
of with your other waste. It is your responsibility to dispose of your waste equipment by handling it over to a
designated collection point for the recycling of waste electrical and electronic equipment. The separate
collection and recycling of your waste equipment at the time of disposal will help to conserve natural resources
and ensure that it is recycled in a manner that protects human health and the environment. For more
information about where you can drop off your waste equipment for recycling, please contact your local city
office, your waste disposal service.

IDRONAUT –Brugherio (MB) OCEAN SEVEN 310 CTD 01-2019
TABLE OF CONTENTS
1INTRODUCTION .............................................................................................................................. 1
1.1 PROBE DESCRIPTION...................................................................................................................... 1
1.2 SAMPLING MODES.......................................................................................................................... 2
1.3 REAL-TIME COMMUNICATIONS ................................................................................................ 2
1.4 WIRELESS COMMUNICATION MODULE "BLUETOOTH®”, “WiFi”................................... 3
1.5 PORTABLE READER ........................................................................................................................ 3
1.6 IDRONAUT TELEMETRY DECK UNIT ........................................................................................ 3
1.7 INTERNAL BATTERIES ................................................................................................................... 4
1.8 EXTERNAL SUBMERSIBLE RECHARGEABLE BATTERY PACKS.......................................... 4
1.9 MAGNETIC POWER ON/OFF SWITCH........................................................................................ 4
1.10 MANAGEMENT PROGRAMMES.................................................................................................. 5
1.11 STANDARD SENSOR SPECIFICATIONS ..................................................................................... 6
1.12 OPTIONAL SENSOR SPECIFICATIONS....................................................................................... 6
1.13 ELECTRONIC SPECIFICATIONS................................................................................................... 6
1.14 PHYSICAL CHARACTERISTICS .................................................................................................... 7
1.15 THE STANDARD SENSORS............................................................................................................ 7
1.15.1 LIFETIME AND HOW TO REPLACE THE IDRONAUT SENSORS......................................... 7
1.15.2 The pressure sensor........................................................................................................................... 7
1.15.3 The temperature sensor .................................................................................................................... 8
1.15.4 The conductivity sensor equipped with the "IDRONAUT seven-ring cell".............................. 8
1.15.5 The oxygen sensor (standard 150bar and 700 bar versions)........................................................ 9
1.15.6 The oxygen sensor maintenance-free version - 5 bar only........................................................ 10
1.15.7 Blue Cap Optical dissolved oxygen .............................................................................................. 11
1.15.8 pH and reference sensors ............................................................................................................... 11
1.15.9 The redox sensor.............................................................................................................................. 13
1.16 CALCULATIONS............................................................................................................................. 14
1.16.1 Polarographic Oxygen sensor ........................................................................................................ 14
1.16.2 pH calculation and pH correction in relation to the sample temperature............................... 14
1.16.3 Conductivity compensated at 20 °C.............................................................................................. 15
1.17 PROBE FIRMWARE OVERVIEW................................................................................................. 16
1.17.1 User interface.................................................................................................................................... 16
1.17.2 Menu & submenu structure ........................................................................................................... 17
1.17.3 Menu header structure.................................................................................................................... 17
1.17.4 Probe Access Rights......................................................................................................................... 18
1.17.5 Data transmission protocol ............................................................................................................ 18
1.17.6 Data transmission protocol: PTP Point-to-point ......................................................................... 18
1.17.7 Acquired data processing and post-processing .......................................................................... 19
1.17.8 Low power consumption................................................................................................................ 19
1.17.9 Configuration ................................................................................................................................... 19
2INSTALLATION AND START UP............................................................................................... 21
2.1 SHIPPING LIST ................................................................................................................................ 21
2.1.1 Laboratory RS232C cable................................................................................................................ 21
2.2 INSTALLATION .............................................................................................................................. 21
2.2.1 Internal and external battery packs............................................................................................... 21

IDRONAUT –Brugherio (MB) OCEAN SEVEN 310 CTD 01-2019
2.2.2 Telemetry Deck Unit installation................................................................................................... 22
2.3 START-UP ......................................................................................................................................... 22
2.3.1 RS232C/RS485 interface - Probe power ON................................................................................. 22
2.3.2 Telemetry interface probe power ON........................................................................................... 22
2.3.3 Standard start-up messages ........................................................................................................... 22
2.4 THE MAIN MENU .......................................................................................................................... 23
2.5 LOW POWER CONSUMPTION.................................................................................................... 24
3DATA ACQUISITION .................................................................................................................... 25
3.1 THE DATA ACQUISITION MENU.............................................................................................. 25
3.2 ACQUIRED PARAMETERS........................................................................................................... 25
3.3 COMMON RULES TO SET UP THE DATA ACQUISITION CYCLE...................................... 25
3.4 COMMMON RULES TO STORE ACQUIRED DATA................................................................ 25
3.5 ON-LINE ACKNOWLEDGEMENT.............................................................................................. 26
3.6 UNATTENDED ACKNOWLEDGEMENT .................................................................................. 26
3.7 UPLOADING DATA STORED IN THE PROBE MEMORY...................................................... 26
3.8 UNATTENDED ACQUISITIONS –IMPORTANT TIPS............................................................ 26
3.8.1 Power consumption reduction....................................................................................................... 27
3.8.2 Warm-up........................................................................................................................................... 27
3.8.3 ON/OFF cycles ................................................................................................................................. 27
3.9 SHIPPING CONDITIONS .............................................................................................................. 27
3.10 SENSORS........................................................................................................................................... 27
3.11 REAL TIME DATA ACQUISITION .............................................................................................. 27
3.12 LINEAR DATA ACQUISITION..................................................................................................... 28
3.12.1 Routine operations to perform unattended linear profiles........................................................ 28
3.12.2 Terminate the unattended linear profile ...................................................................................... 29
3.12.3 Step-by-step Linear Profile procedure.......................................................................................... 29
3.13 TIMED DATA ACQUISITION....................................................................................................... 31
3.13.1 Terminate a timed data acquisition............................................................................................... 32
3.13.2 Automatic power OFF procedure ................................................................................................. 33
3.13.3 Accidental power ON cycle............................................................................................................ 33
3.13.4 Magnetic power ON/OFF switch................................................................................................... 33
3.13.5 Step-by-step procedure................................................................................................................... 33
3.14 CONDITIONAL DATA ACQUISITION ...................................................................................... 35
3.14.1 Terminate the Conditional data acquisition ................................................................................ 36
3.15 CONTINUOUS DATA ACQUISITION........................................................................................ 38
3.15.1 Step-by-step procedure................................................................................................................... 38
3.15.2 Routine operations to perform unattended continuous profiles .............................................. 39
3.15.3 Terminate the Continuous data acquisition................................................................................. 39
3.16 BURST DATA ACQUISITION ....................................................................................................... 41
3.16.1 Field operations................................................................................................................................ 41
3.16.2 Ending the unattended data acquisitions..................................................................................... 41
4DATA STORAGE............................................................................................................................. 43
4.1 MEMORY ORGANIZATION......................................................................................................... 43
4.1.1 Cast area............................................................................................................................................ 43
4.1.2 Data records...................................................................................................................................... 43
4.1.3 Data Sets............................................................................................................................................ 44
4.2 MEMORY MANAGEMENT........................................................................................................... 44
4.3 SHOW MEMORY STATUS ............................................................................................................ 44

IDRONAUT –Brugherio (MB) OCEAN SEVEN 310 CTD 01-2019
4.4 SHOW STORED DATA................................................................................................................... 44
4.5 MEMORY DELETE DATA ............................................................................................................. 45
4.6 INITIALIZE DATA MEMORY....................................................................................................... 45
5SENSOR CALIBRATION ............................................................................................................... 47
5.1 CALIBRATION STORING LAYOUT............................................................................................ 47
5.1.1 Parameter/Sensor logical codes ..................................................................................................... 47
5.2 CALIBRATION GLP (GOOD LABORATORY PRACTICE)...................................................... 47
5.3 SENSOR CALIBRATION FUNCTIONS ....................................................................................... 47
5.3.1 Updating the calibration information........................................................................................... 48
5.4 CALIBRATE THE SENSORS.......................................................................................................... 48
5.4.1 Selecting a wrong sensor ................................................................................................................ 48
5.5 CUSTOMIZED CALIBRATION PROCEDURE........................................................................... 48
5.5.1 Pressure sensor................................................................................................................................. 49
5.5.2 Temperature & Conductivity sensor calibration......................................................................... 49
5.5.3 Simple check of conductivity sensor calibration......................................................................... 50
5.5.4 Oxygen sensor calibration .............................................................................................................. 50
5.5.5 pH sensor calibration ...................................................................................................................... 52
5.5.6 Redox sensor calibration................................................................................................................. 53
5.6 EXTENDED CALIBRATION PROCEDURES.............................................................................. 54
5.6.1 SEAPOINT OEM Turbidity Meter ................................................................................................ 55
5.6.2 SEAPOINT OEM Fluorometer....................................................................................................... 56
5.6.3 WETLabs - C-STAR Transmissometer.......................................................................................... 56
5.6.4 WETLabs - ECO Triplet Sensor..................................................................................................... 58
5.6.5 LICOR - PAR Sensor........................................................................................................................ 59
5.6.6 Single/Three-Channel Fluorimeter................................................................................................ 61
5.6.7 TURNER DESIGNS –CYCLOPS-7 calibration coefficients....................................................... 63
5.7 CALIBRATING LOGGING ............................................................................................................ 63
6SERVICE, DIAGNOSTICS AND CONFIGURATION ............................................................... 64
6.1 THE SERVICE MENU ..................................................................................................................... 64
6.1.1 Raw data acquisition in ADC counts or mV................................................................................ 64
6.1.2 Probe diagnostic functions ............................................................................................................. 64
6.1.3 Probe configuration......................................................................................................................... 66
7PROBE MAINTENANCE............................................................................................................... 71
7.1 OXYGEN SENSOR........................................................................................................................... 71
7.1.1 Important remark on oxygen measurement ................................................................................ 71
7.1.2 Green membrane ............................................................................................................................. 71
7.1.3 Refilling oxygen sensor cap with electrolyte ............................................................................... 72
7.1.4 Membrane replacement (oxygen membrane cap)....................................................................... 72
7.1.5 Replacement of membrane(s) using the OXYGEN SENSOR MAINTENANCE KIT: ........... 72
7.1.6 Oxygen sensor cleaning .................................................................................................................. 73
7.1.7 Oxygen sensor check in the absence of oxygen........................................................................... 74
7.2 REFERENCE SENSOR..................................................................................................................... 74
7.3 pH SENSOR ...................................................................................................................................... 74
7.3.1 To etch the sensor, perform the following: .................................................................................. 75
7.3.2 Important remark on the pH measurement................................................................................. 75
7.4 CONDUCTIVITY SENSOR............................................................................................................. 75
7.4.1 Important remarks on conductivity measurement..................................................................... 75
7.4.2 Conductivity sensor cleaning......................................................................................................... 76

IDRONAUT –Brugherio (MB) OCEAN SEVEN 310 CTD 01-2019
7.5 REDOX SENSOR.............................................................................................................................. 76
7.6 TEMPERATURE SENSOR .............................................................................................................. 76
7.7 PRESSURE SENSOR ........................................................................................................................ 76
7.8 INTERNAL BATTERY .................................................................................................................... 76
7.8.1 Internal battery pack endurance.................................................................................................... 77
7.8.2 Oxygen sensor polarization device ............................................................................................... 78
7.9 ROUTINE MAINTENANCE SCHEDULE ................................................................................... 78
8TROUBLESHOOTING.................................................................................................................... 79
APPENDIX
Appendix A Internal & external battery pack description 80
Appendix B Data Processing Function Priming 85
Appendix C Optional sensors calibration and configuration 87
Appendix D Advanced configuration 105
Appendix E Rosette interfacing 107
Appendix F IDRONAUT Windows Terminal Emulation Programme 113
Appendix G Antifouling device 119
Appendix H Wireless “Bluetooth™” Interface 121
Appendix I Submersible connectors and cable care 122
Appendix L Sensor cleaning and care 125
Appendix M AUV Version 128

SECTION ONE –SYSTEM DESCRIPTION
IDRONAUT –Brugherio (MB) OCEAN SEVEN 310 CTD 01-2019
1
1INTRODUCTION
This section describes the main components of the OCEAN SEVEN 310 CTD multi-parameter probe.
1.1 PROBE DESCRIPTION
The OCEAN SEVEN 310 CTD multi-parameter probe represents a real breakthrough in the
concept of miniaturization, integration and performances. Thanks to the adoption of a new
generation of electronic devices, the OS310 can interface up to 14 analogue sensors and three
digital sensors (see list) and can guarantee sampling rates up to 28Hz, all of the above contained
in a CTD with very small diameter (see housings) and very low power consumption. Operator
can easily select the OS310 sampling rate among 2,4,8,12, up to 28 Hz (sample per second)
according to the required monitoring or profiling activity.
The OCEAN SEVEN 310 is equipped with the well-known and proven IDRONAUT pressure
balanced full ocean depth, pump free and long-term stability sensors. Central to which, is the
high accuracy seven-platinum-ring conductivity sensor, which can be cleaned in the field without
the need for re-calibration. Furthermore, an optional UV-LED (280nm) integrated into the
conductivity cell, sterilize the sample under measurement, thus avoiding the early growth of
biofouling inside the quartz measuring cell.
For added flexibility, the OCEAN SEVEN 310 CTD multi parameter probe can be operated in
either verbose or non-verbose modes, the latter being especially convenient for system
integrations on buoys data loggers, ROVs and AUVs, SAVs making this CTD an ideal choice for
both on-line profiling and self-recording moored applications.
Data is output using the standard RS232C interface or the telemetry option available for on-line full
ocean depth real-time data transmission. Other interfaces like RS485 and Wireless (Bluetooth, WiFi) can
be optionally installed.
Submersible bulkhead connectors, installed on the top cover, provide optional external power supplies
and data exchange with a suitable surface system. Also on the top cover, a stainless steel eyebolt is
provided with which to attach the probe to a cable. The connector area and the sensors area are protected
against accidental damage by titanium cages. Optional copper screens can be fitted to the sensor area to
limit biofouling in situations where the probe will remain immersed for extended periods of time (see
description in the dedicated appendix). The response time constant is 50ms for the CTD sensors and 3s
for oxygen, pH and redox. Software compensation is provided for changes in the internal temperature
of the probe, to guarantee both high performance and long-term stability. The electronic boards are
fitted in a sealed housing made of either PPS white plastic, AISI316 Stainless Steel or Titanium,
depending on favourite deployment pressure and weight requirements.
The OCEAN SEVEN 310 CTD in its basic configuration is equipped with three sensors: pressure,
temperature and conductivity. Other bulkhead sensors can be optionally added, like: highly precise
pressure transducer (0.01%), dissolved polarographic oxygen, optical dissolved oxygen, pH, redox,
reference electrode and the OEM Seapoint Turbidity Meter. Oxygen concentration in ppm, salinity,
density, sound velocity and other derived parameters are automatically calculated according to
UNESCO recommendations and formulae.
It is possible to interface external sensors or equipment like: altimeters, fluorometers, transmissometers,
PAR sensors, Rosette sampling systems, etc.
The following equipment is currently interfaced:
❖GENERAL OCEANICS - Rosettes mod. 1018.
❖IDRONAUT MISS miniaturized sampling system
❖IDRONAUT –High precision 0.01% pressure transducer.
❖IDRONAUT - String and Weight Bottom Sensor.

SECTION ONE –SYSTEM DESCRIPTION
IDRONAUT –Brugherio (MB) OCEAN SEVEN 310 CTD 01-2019
2
❖IDRONAUT –Blue Cap Dissolved Oxygen sensor.
❖WET Labs - C-Star Transmissometer and ECO single/three channel Fluorometer.
❖CHELSEA - Unilux and Trilux Fluorometers.
❖SEAPOINT - Fluorometers and Turbidity Meter.
❖TURNER DESIGNS –Cyclops-7 Fluorometers.
❖D & A INSTRUMENT COMPANY - OBS-3 Sensor.
❖LI-COR - LI-192SA Underwater and LI-193SA Spherical Underwater Quantum sensors.
❖BIOSPHERICAL INSTRUMENTS - QSP-2200 –QSP-2300 Quantum Scalar PAR Sensor.
Other equipment or sensors can be interfaced upon request.
1.2 SAMPLING MODES
The probe is microprocessor-controlled and can be programmed to acquire and process data by various
methods. Processed or raw data can be either transmitted in real time or stored inside the instrument.
Data acquisition methods includes:
➢Pressure.Data is sampled at regular pressure intervals. Multiple profiles can be obtained by
switching the probe ON and OFF.
➢Timed.The probe collects a series of samples and then sleeps for the configured time interval
before waking up again and repeating the acquisitions. Time interval can be configured from 5s
up to 1 day. Battery power is conserved while the probe is in sleep mode.
➢Conditional. Data is sampled at configurable sampling rates starting when the selected parameter
overcomes the configured boundary. Sampling continues until the selected parameter falls below
the configured boundary. Whenever the acquisition cycle starts, a configurable sampling rate
0.1..28Hz is used. Monitoring of the selected parameter occurs at the configurable interval
between 5s up to 1 day.
➢Continuous. Data is sampled at configurable sampling rates starting when the operator switches
on the probe. Sampling continues until the probe is switched off. Multiple cycles can be obtained
by switching the CTD ON and OFF.
➢Burst. Burst sampling carried out at configured intervals: 5s up 1 day.
➢Real-time.Data is sent to the control system at the chose sampling rates.
The slender profile of the probe and the pressure-compensated sensor suite permit operation in either
high speed profiling or in fixed depth monitoring applications to full ocean depths.
1.3 REAL-TIME COMMUNICATIONS
The OCEAN SEVEN 310 multi-parameter probe communicates with a computer via a standard RS232C
interface. Real-time data can be acquired by means of the REDAS-5 Windows software. An optional
RS485 interface overcomes the limitation of the RS232C cable maximum length (200 m) and allows the
probe to transmit data through distances up to 1000 m. The communication speed is user selectable
among: 9600, 19200, 38400 and 115200 (38400 default). The probe can also be equipped with the
IDRONAUT data telemetry, which overcomes the cable limitations and allows the real-time
communication with the probe through the standard oceanographic coaxial cables. It is important to
mention that the OCEAN SEVEN 310 CTD is insulated with respect to the communicating device,
independently of the kind of interface that is used: RS232C, RS485, telemetry. Insulation guarantees that
the sensors are not affected or disturbed by ground loops or stray currents.
Connection type
Max cable length
Max. transfer rate
RS232C
200 m
115k2 bps
RS485
1000 m
115k2 bps
Telemetry
10000 m
14k4 bps
The above performance is obtained using the 6.4 mm diameter (1/4 inch) Rochester cable
1-H-255 which has an electrical resistance of 23 /km and a capacity of 138 pF/m.

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1.4 WIRELESS COMMUNICATION MODULE "BLUETOOTH®”, “WiFi”
The OCEAN SEVEN 310probe can be optionally equipped with a wireless adapter which allows
bidirectional full-duplex communications between the OCEAN SEVEN 310 probe and a personal
computer (Desktop, Laptop) or PDA devices equipped with a compatible wireless device. A thorough
description of the wireless adapter can be found in the dedicated appendix.
1.5 PORTABLE READER
The OCEAN SEVEN 310 probe can be interfaced with a portable lightweight and extremely rugged
reader based on the Windows Mobile™ software for Pocket PC. Through this device, it is possible to
perform the operations usually carried out by means of a portable
personal computer, but without all limitations that the use of a portable
computer in the field and in hostile environments normally implies, like:
battery endurance, display reading under sunlight, water and dust
tightness, weight, etc.
The “Portable Reader” interfaces the OCEAN SEVEN 310 probe through
a built-in RS232C interface and dedicated IDRONAUT programmes,
specifically developed for
the Windows Mobile PC
operating system: ZTERM
and µREDAS. These
programmes interface the
OCEAN SEVEN 310 probe
and allow the operator to
directly dialogue with the
probes directly, thus
performing: sensor calibration, real-time data acquisition,
probe configuration, etc. All these operations are possible
because of the OCEAN SEVEN 310 probe functions
included in the management firmware. Furthermore, the
“Portable Reader” not only shows real-time data sent by
the OCEAN SEVEN 310 probe, but also stores it. Data is
stored in binary files using the “Portable Reader” main or
extension “Flash” memory, which can be later transferred
to a desktop personal computer. Data acquired by means
of the “µREDAS” programme can be imported later by the
REDAS-5 programme. Data storage capability of the
“Portable Reader” is only limited by the size of the installed
“Flash” compact memory card. The “Portable Reader” can operate for up to 15 hours continuously.
Autonomy of operation of the interfaced OCEAN SEVEN 310 probe depends on the battery installed
inside the probe and on the sensor suite.
1.6 IDRONAUT TELEMETRY DECK UNIT
The IDRONAUT Telemetry Deck Unit powers
and interfaces, by coaxial oceanographic cables,
the OCEAN SEVEN 310 probe with a personal
computer RS232C interface. The Deck Unit is
provided with a transceiver (modem) which allows half-duplex communication with the OCEAN
SEVEN 310 probe. Two types of Deck Units are available: Portable and On-Board. The first one is
provided with an internal rechargeable lead battery (12VDC, 7 A/h) which permits OCEAN SEVEN 310
probe operation even in the absence of the mains supply. The On-
Board MKPlus Deck Unit is housed in a 19” rack-mountable unit
and is designed for on-board operations. The On-Board MKPlus
deck unit provides high voltage telemetry power supply: 220 VDC
to allow the OCEAN SEVEN 310 probe to interface and power
several additional instruments like: GENERAL OCEANICS Rosette
1018, Fluorometer, Turbidity meter, etc.

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1.7 INTERNAL BATTERIES
The OCEAN SEVEN 310 probe housing has in its upper part enough space to accommodate an internal
battery pack. This is used whenever the probe carry out unattended acquisition cycles without the
connection in real time with a surface unit (PC). Different types of battery can be installed in the CTD
housing:
➢1x Size “A” Li-SOCI2 Lithium-thionyl chloride non rechargeable battery 3.6V, 2.4Ah
➢3x Size “AA” 1.5V Alkaline non rechargeable battery assembled in a single pack 4.5V
➢1x Size “C” Li-SOCI2 Lithium-thionyl chloride non rechargeable battery 3.6V, 8.4Ah
➢1x Li-Ion rechargeable IDRONAUT custom battery pack 3.7V,4.5 Ah
Whenever the OS310 operates in Timed, Burst and Conditional modes, the battery endurance is
considerably extended because the CTD enters a deep sleep mode between acquisitions. When the
probe is not used for long periods (e.g. 2 weeks or more), we suggest disconnecting the internal battery
pack connector from the probe electronics or removing the internal battery pack from the probe to
prevent the internal batteries from damaging the probe due to battery acid leakage. This is why the
OCEAN SEVEN 310 is shipped without batteries installed. Please be aware that it is not possible to
recharge the battery pack when it is installed inside the probe
1.8 EXTERNAL SUBMERSIBLE RECHARGEABLE BATTERY PACKS
To overcome the limited autonomy of the internal battery pack, IDRONAUT developed two external
submersible rechargeable battery packs that considerably increase the probe operating autonomy.
❖Submersible rechargeable battery pack (Ø 75 x 315 mm POM), 1500 m max depth operation.
❖Submersible rechargeable battery pack (Ø 66 x 315 mm Titanium), 7000 m max depth operation.
The external battery pack is held by the probe by means of a POM flanges and connected to the RS232C
input/output bulkhead connector by means of a submersible cable. The external battery pack is
internally protected by means of a multi-fuse.
Note
The presence of the external battery pack does not interfere with the installation of the internal battery pack. The
CTD drains energy from the higher voltage battery pack.
1.9 MAGNETIC POWER ON/OFF SWITCH
The OCEAN SEVEN 310 probe is equipped with a magnetic power ON/OFF
switch, which allows the operator to effectively switch ON and OFF the
probe. The probe is also able to switch on and off by itself whenever it
performs self-recording acquisition cycles and uses the internal and/or
external battery pack.

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5
The magnetic power ON/OFF switch is not used and is bypassed when the
probe is used with telemetry (please remove the internal batteries, if any, before
operating the probe through the telemetry system).
This switch also allows the operator to easily deploy a probe that is pre-
configured to carry out unattended data acquisition cycles. When switching
ON/OFF the probe by means of the magnetic switch, please wait at least 10
seconds between consecutive ON/OFF cycles.
1.10 MANAGEMENT PROGRAMMES
IDRONAUT programmes designed for the Windows 32/64bit operating systems allow the operator to
communicate with the OCEAN SEVEN 310 probe to perform attended or unattended data acquisitions.
Programmes include functions to upload data from the internal non-volatile data memory when the
probe acts as a logger. The available programmes are:
ITERM: IDRONAUT Terminal Emulation program and probe management to easily communicate
with the OCEAN SEVEN 310 CTD multi-parameter probe. Diagnostic and dedicated
functions are present.
ZTERM: Terminal Emulation Program for Windows Mobile Operating system. Terminal emulation
program to easily communicate with the OS310 CTD multi-parameter probe.
uREDAS IDRONAUT real-time data acquisition software for Windows Mobile operating system. It allows
acquiring and displaying data in real time storing it for later retrieval and processing using
REDAS-5 program. While acquiring, up to six different parameters are shown on screen.
REDAS-5: Real-time data acquisition, processing and presentation program, which allows the
numerical display and plotting of the standard sensors and the derived variables such as
salinity, sound speed, density, according to the UNESCO formulas and recommendations.
MULTIPLEX: Multiplex programme, which allows the acquisition from up to 16 OCEAN SEVEN 310CTDs
connected to a single personal computer. Data acquired in real time by means of the Multiplex
program can be later processed using the REDAS-5 program.

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1.11 STANDARD SENSOR SPECIFICATIONS
The OS310 multiparameter CTD can be equipped with the following sensors to measure:
1.12 OPTIONAL SENSOR SPECIFICATIONS
Among others, the OCEAN SEVEN 310 CTD can be optionally equipped with the Highly Accurate
Precise (0.01%) Pressure Transducer, the optical IDRONAUT OEM SEAPOINT Turbidity and
Fluorometer sensors, the IDRONAUT OEM CHELSEA Single-Channel and Three-Channel
Fluorimeters.
1.13 ELECTRONIC SPECIFICATIONS
Real-time and logging: up to 28 Hz
Interfaces RS232C, RS485, TTL, Data telemetry (QAM) up to 10Km; Wireless:
WiFi/Bluetooth
Real-time clock accuracy: 3 ppm/year
Power supply: Battery: 2.9..5.0 VDC; running: 90 mA @ 3.6VDC; standby 8 µA @3.6VDC
External power: 9..32 VDC; running: 67 mA @ 12VDC; standby 8 mA @12VDC
Data telemetry: Low voltage: 18..60 VDC; High voltage: 90..220 VDC
Parameter Range Accuracy Resolution Time Constant
Pressure 0..7000 dbar(3) 0.05 % FS 0.0015 % FS 50 ms
Temperature -5..+50 °C 0.0015 °C 0.0001 °C 50 ms
Conductivity salt water 0..90 mS/cm 0.0015 mS/cm 0.0001 mS/cm 50 ms (1)
fresh water 0..7000 µS/cm 5 µS/cm 0.1 µS/cm 50 ms (1)
brine 0..350 mS/cm(5) 0.010 mS/cm 0.0001 mS/cm 50 ms
Oxygen (polarographic) 0..50 ppm 0.1 ppm 0.01 ppm 3 s 2)
0..500 %sat. 1 %sat. 0.1 %sat. 3 s 2)
Oxygen (optical) 0..45 mg/l 0.1 mg/l 0.025 mg/l 5 s
0..250 %sat. ±0.2 %sat. 0.05 %sat. 5 s
pH 2..12 pH 0.01 pH 0.1 mpH 3 s 4)
Redox -1000..+1000 mV 1 mV 0.1 mV 3 s
(1) At 1 m/second flow rate. (2) From nitrogen to air. (3) Other standard pressure transducers: 10, 40, 100, 200, 500, 1000, 2000, 4000, 7000, 10000 dbar.
(4) Differential pH preamplifier, 10131014 ohm input impedance. (5) Optional extended range, available upon request
The fundamental properties of seawater like: Salinity, Sound Speed, Water Density, Oxygen ppm are obtained using the algorithms described in the
UNESCO “Technical papers in marine science no. 44”. The fresh water properties like: TDS (Total Dissolved Solids), Fresh Water Conductivity
corrected at 20°C and 25°C are automatically calculated.
Parameter Range Accuracy Resolution Time Constant
Pressure (highly accurate) 0..7000 dbar(1) 0.01 % FS 0.002 % FS 50 ms
Turbidity meter 0..>2500 FTU 0.1 FTU 0.025 FTU 3s (2)
Fluorometer 0..150 µg/l 0.02 µg/l 0.01 µg/l 3s (2)
PAR 0..10 µA 0.05 µA 0.01 µA
UNILUX (single-channel) 0..100 µg/l (3)
TRILUX (three-channel) 0..100µg/l (3)
CYCLOPS fluorometers 0..100 µg/l (3)
ECO fluorometers 0..100 µg/l (3)
Water sampling system General Oceanics 1018 Rosette, IDRONAUT MISS miniaturized 6 Bottle water sampling system
(1) Other standard pressure transducers: 100, 1000,2000, 4000, 7000 dbar. (2) Provided with auto-range ,25,125,500, >2500 FTU; 5,15,50,150 µg/l.
(3) Chlorophyll a, Phycocyanin, Phycoerythrin for algae monitoring; Rhodamine WT or Fluorescein for dye tracing applications;
Nephelometer for turbidity monitoring.

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7
1.14 PHYSICAL CHARACTERISTICS
Housings:
1000 dbar
1500 dbar
2000 dbar
6000 dbar
7000 dbar
7000 dbar
(AISI316)
(POM)
(POM)
(Titanium)
(Titanium)
(Titanium)
Dimensions:
diameter
48 mm
100 mm
75 mm
48 mm
75 mm
89 mm
length
715 mm
710 mm
660 mm
660 mm
630 mm
720 mm
Weight:
in air
1.3 Kg
4.2 kg
3.3 Kg
2.1 Kg
5.0 Kg
8.0 Kg
in water
0.7 kg
0.2 Kg
1.7 kg
1.3 Kg
3.8 Kg
4.3 Kg
1.15 THE STANDARD SENSORS
This section provides a detailed presentation of the OCEAN SEVEN sensors.
1.15.1 LIFETIME AND HOW TO REPLACE THE IDRONAUT SENSORS
The IDRONAUT sensors are all pressure compensated and, in particular, the physical sensors (pressure,
temperature and conductivity) can last many years, if properly used. They are high-quality sensors, as
they are well known by oceanographers to measure salinity with great accuracy.
If thoroughly maintained by their respective hydrating caps and solutions, the IDRONAUT pH and
reference sensors can last several years. The sensor replacement requires that the closure screws on the
top head of the probe be unscrewed with a common screwdriver and the cylindrical housing be
removed (this takes very few minutes). The wire sensors are tin soldered on their respective connection
points placed on the printed circuit board. All sensor heads have a standard 12 mm diameter and are
provided with two O-rings (Parker 12-2) for sealing. This means that every sensor can be fitted in any
of the five sensor head holes. The pressure sensor is a high-quality transducer, which lasts many years
if properly used. Its replacement is not very easy and, moreover, it requires a Dead Weight Tester
System to obtain the factory calibration accuracy of 0.05% full scale.
1.15.2 The pressure sensor
The pressure sensor is a high quality strain gauge, centrally mounted on the probe base, capable of
generating a linear signal output, thus giving a resolution of 0.03% over the whole measuring range of
0 - 10000 dbar
Type: strain gauge
Measurement range: 0...10000 dbar
Accuracy: 0.05%FS
Resolution 0.002%FS
Response time: 50 ms @1 m/s
Measurement bridge resistance: @ 25°C Ω 3500 ± 20%
Excitation current: 0.6 mA
Insulation: @ 50 VCC MΩ 100
Operating temperature: °C -30…100
Sensor body: AISI 316L
Compensation: automatic compensation for temperature variations; not
compensated for the barometric pressure variations.
Life: unlimited.
Calibration frequency: monthly.
Maintenance: offset calibration in air.

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1.15.3 The temperature sensor
The temperature sensor consists of a platinum resistance
thermometer (type Pt 100 ohms at 0°C), fitted on a thin stainless-steel
housing, able to withstand up to 700 bar. The sensor has a very low
response time (50 ms) and a high stability of reading with ageing.
The drift of reading (sensor plus associated electronics) is less than
0.0003 °C per year.
Type: Pt100@0°C
Measurement range: -3..+50 °C
Accuracy: 0.003 °C
Resolution: 0.0002 °C
Response time: 50 ms @1 m/s
Maximum pressure: 700 bar
Sensor body: AISI 316L
Life: unlimited
Calibration frequency: yearly
Compensation: none.
Maintenance: none.
1.15.4 The conductivity sensor equipped with the "IDRONAUT seven-ring cell"
The conductivity sensor is a unique flow-through self-flushed cell with seven platinum ring electrodes.
The central ring is excited with alternate current flowing to both the outermost rings. The two adjacent
pairs of rings sense the relative drop in voltage due to the electrical conductivity of the measured water.
The outermost pair of rings is grounded to shield the measuring cell from any outside electrical
interference. The cell is mounted in a special cylindrical plastic body, which guarantees thermic
insulation and is filled with silicone oil and provided with a rubber bellow to achieve pressure
compensation.
The IDRONAUT conductivity sensor and its associated electronics
are designed to work both with plain and black platinised platinum
electrodes These electrodes have the advantage that, they can be used
in both clean and dirty water without the fear of contamination.
Should electrode contamination occur, they can be easily cleaned
(even with up to 30% hydrochloric acid) without affecting the CTD
performance or requiring re-calibration. Because of its big internal
diameter and short length, the cell does not need a pump, as it is
easily flushed during profiles.
The other conductivity flow cell sensors available on the market do
not have the technology of the “IDRONAUT seven-ring cell”.
The small, closely spaced temperature and conductivity free-flow
sensors eliminate the need for adding pumping. Time constant of the
conductivity sensor is 50 ms, at 1 meter per second water flow.
Measurement cell: 7 platinum rings deposited inside
a quartz tube. Internal diameter
8mm, length 45mm.
Measurement range: 0..70 mS/cm
Accuracy: 0.003 mS/cm
Resolution: 0.0003 mS/cm
Response time: 50 ms @1 m/s
Max pressure: 700 bar
Sensor body: black plastic and titanium
Compensation: automatic compensation of the pressure and thermal effect on the
cell geometry are performed by the acquisition software.
Life: unlimited.

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Calibration frequency: yearly.
Maintenance: cleaning using the IDRONAUT “Conductivity sensor cleaning
solution”.
1.15.5 The oxygen sensor (standard 150bar and 700 bar versions)
The oxygen sensor is of the polarographic type and consists of two half-cells, the anode and the cathode.
The anode is a silver tube inside the sensor, which encircles a glass body where a platinum wire, forming
the cathode, is sealed. The platinum wire (cathode) ends at the tip of the sensor where the glass body is
rounded. A special membrane cap with a gas-permeable replaceable membrane screws onto the sensor.
The inside of the cap is filled with a special electrolyte which allows the current (measuring) to flow
between the anode and the cathode. The membrane is shielded from accidental bumps by a protective
ring. The anode acts as a reference cell, providing a constant potential with respect to the cathode. The
cathode, where oxygen is consumed or reduced, is separated from the sample to be analyzed by a thin
layer of electrolyte and a special composite membrane. The electrolyte permits the chemical reaction to
occur whereas the membrane constitutes a barrier against ions and other substances. By applying a
polarizing voltage to the half-cells, the sensor develops a current proportional to the concentration of
oxygen in the sample in front of the cathode. Oxygen from the sample is drawn across the membrane,
at the sensor tip, in the area of the cathode. The applied polarization voltage is such that the sensor only
responds to oxygen. The sensor is insensitive to nitrogen, nitrous oxide, carbon dioxide and other gases.
In order to avoid stray ground current leaks, in case of membrane leaks, the anode is kept at ground
potential while the cathode is polarized at a fixed negative voltage. The oxygen sensor limits stirring
effects on the measurement and reads at least 97% of the true value, even with a stagnant aqueous
sample. This is because the very small cathode area and special cathode geometry, associated with a
unique composite membrane, minimize the consumption of the oxygen contained in the sample in
contact with the membrane. The function of this sensor depends on the reduction of oxygen at the
cathode, as expressed by the formula:
O2+ 2 H2O + 4e->>> 4 OH-
The developed electrons represent the measuring current and are supplied by the silver/silver chloride anode.
Standard version, 150 bar
Type: polarographic with Pt/Ir cathode and
Ag(99.99%) anode.
Measurement range: 0... 50 ppm 0… 500% sat.
Accuracy: 0.1 ppm 1 % sat.
Resolution: 0.01 ppm 0.1% sat.
Polarization voltage: 650 mV DC.
Response time: 3s (green membrane @20°C)
0.9 s (blue membrane @20°C)
Max Pressure: 150 bar.
Sensor body: plastic and titanium.
Compensation: automatic compensation of pressure and
thermal variations.
Life: 2 years if intensively used to perform
continuous monitoring, up to 4 years if
used weekly to perform daily profiling or
monitoring.
Calibration frequency: weekly.