Endress+Hauser Memobase Plus CYZ71D Operating Instructions Manual
Endress+Hauser Memobase Plus CYZ71D Operating Instructions Manual

Endress+Hauser Memobase Plus CYZ71D Operating Instructions Manual

Pc-based multichannel liquid analysis with database
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BA00502C/07/EN/02.13
71227351
Valid as of:
Softwareversion 01.02.00
Products
Operating Instructions
Memobase Plus CYZ71D
PC-based multichannel liquid analysis
with database
Solutions
Services

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Summary of Contents for Endress+Hauser Memobase Plus CYZ71D

  • Page 1 Products Solutions Services BA00502C/07/EN/02.13 71227351 Valid as of: Softwareversion 01.02.00 Operating Instructions Memobase Plus CYZ71D PC-based multichannel liquid analysis with database...
  • Page 2 Date Version Software modifications Documentation: edition 10/2013 01.02.00 Extended functionality BA00502C/07/EN/02.13 • Interface to connect to an Oracle database • Implementation of the CPSx6D combination electrode • Interface for data exchange with the W@M portal • Tag name and Memoclip in the calibration report •...
  • Page 3: Table Of Contents

    Memobase Plus CYZ71D Table of contents Document information ..5 Measurement ....33 Warnings ......5 Main and secondary values .
  • Page 4 Memobase Plus CYZ71D 16 Accessories ....81 16.1 Accessories for Memobase Plus CYZ71D ......81 16.2 Measuring cable .
  • Page 5: Document Information

    Memobase Plus CYZ71D Document information Document information Warnings Structure, signal words and color coding of warning information are in compliance with ANSI Z535.6 specifications ("Product safety information in product manuals, instructions and other collateral materials"). Structure of information Meaning This symbol alerts you to a dangerous situation .
  • Page 6: Basic Safety Instructions

    Basic safety instructions Memobase Plus CYZ71D Basic safety instructions Requirements for personnel ‣ Installation, commissioning, operation and maintenance of the measuring system must only be carried out by trained technical personnel. ‣ The technical personnel must be authorized by the plant operator to carry out the specified activities.
  • Page 7: Operational Safety

    The product must be returned if repairs or a factory calibration are required, or if the wrong product has been ordered or delivered. According to legal regulations Endress+Hauser, as an ISO-certified company, is required to follow certain procedures when handling returned products that are in contact with the medium.
  • Page 8: Safety Instructions For Electrical Equipment

    Identification Memobase Plus CYZ71D Safety instructions for electrical equipment in hazardous areas • The MemoLink must never be used in hazardous areas! The MemoLink is not designed as a field device for installation in industrial environments. • The MemoLink, which is approved in accordance with EU type-examination certificate BVS 12 ATEX 079 X, ensures that the "intrinsic safety"...
  • Page 9 Memobase Plus CYZ71D Identification 3.1.2 Nameplate: DVD with software The following information concerning the DVD with the software can be found on the nameplate: • Serial number • License key • Software version 3.1.3 Serial number and order code You will find the order code and serial number of your device: •...
  • Page 10: Scope Of Delivery

    Identification Memobase Plus CYZ71D Scope of delivery The scope of delivery comprises: • Installation DVD with "Memobase Plus" setup, Operating Instructions and video clips • Serial number and license key • 1 to 4 MemoLink sensor connection boxes • 1 to 4 Memosens cables CYK20 •...
  • Page 11: Memobase Plus

    Memobase Plus CYZ71D Memobase Plus Memobase Plus Features Memobase Plus is a software package offering central management of measurement data, calibration data and sensor data for sensors with Memosens technology. It allows end-to-end documentation of data relevant to your sensor and measuring point, e.g.: •...
  • Page 12: Installation

    Installation Memobase Plus CYZ71D Installation Installation wizard The installation wizard guides you through the installation of the Memobase Plus software. The wizard also contains the update function. Therefore, if you want to update your Memobase Plus software you should also start the installation wizard.
  • Page 13 Memobase Plus CYZ71D Installation Click Next to start installing Memobase Plus. The license agreement appears. – Please read the license agreement carefully. – Select I accept the terms in the License Agreement and click Next to continue the installation procedure.
  • Page 14 Installation Memobase Plus CYZ71D Select the database management system that you want to install. If you want to install PostgreSQL Server, continue with Step 6. If you want to use an Oracle database, continue with Step 10. If you want to install the PostgreSQL Server, click Next.
  • Page 15 Memobase Plus CYZ71D Installation If you want to change the installation location, click Browse and select the appropriate folder. Click Next. Endress+Hauser...
  • Page 16 Installation Memobase Plus CYZ71D Choose whether you want to use the Default settings or your Own settings. ‣ The following database parameters are predefined in the default settings: – Server name: localhost – Connection timeout: 60 s – User name: postgres –...
  • Page 17 Memobase Plus CYZ71D Installation Please contact your IT department for a central PostgreSQL server installation. Initialization can be performed using the "Reset database" button. The following settings must be checked to ensure access via the network is possible: – postgres.conf: listen_addresses = ’*’...
  • Page 18 Installation Memobase Plus CYZ71D 10. Click Install. 11. Click Finish to finish the installation. Endress+Hauser...
  • Page 19: License Activation

    Memobase Plus CYZ71D Installation License activation Functions of Memobase Plus which are independent of the sensor - such as user administration - are available after the installation. To be able to use the complete range of functions, you must register your license via the Internet.
  • Page 20 Installation Memobase Plus CYZ71D • The activation code is generated. Follow the instructions on the screen. You can copy the activation code to the clipboard via the Copy to clipboard button. A window opens when you click the link in Step 2. In this window, enter the activation code and follow the instructions.
  • Page 21 Memobase Plus CYZ71D Installation • If you have received the unlock code from Endress+Hauser at the e-mail address that you specified, enter this code in the "Unlock Code" field. Click OK on the bottom left. • You can now use the full range of functions of Memobase Plus.
  • Page 22: Importing Data

    Installation Memobase Plus CYZ71D Importing data If you have been working with Memobase CYZ41D up until now, you can import your data into Memobase Plus CYZ71D. Start the DBConverter.exe application on the DVD. Under "Source Database" specify the database to be imported.
  • Page 23: Database Backup

    Memobase Plus CYZ71D Installation Database backup To make a backup copy of your Memobase Plus PostgreSQL database, please proceed as follows: Start the pgAdmin3.exe. In the standard configuration, this application can be found in the following folder: C:\Program Files\PostgreSQL\9.1\bin Double-click "PostgreSQL 9.1 (localhost:5436)". The "Connect to Server" window opens.
  • Page 24: Connection

    Connection Memobase Plus CYZ71D Connection Dimensions of the MemoLink sensor connection box a0017142 Fig. 1: Dimensions of MemoLink The MemoLink boxes can be stacked on top of one another. In such situations, the "Power / Data" LED is still easily visible.
  • Page 25: Measuring System

    • 1 USB cable • 1 MemoLink • 1 Memosens cable • 1 sensor with Memosens technology a0017164 Fig. 2: Measuring system for Memobase Plus CYZ71D PC with software USB hub USB cable 1 to 4 MemoLink boxes CYK20 Memosens cable 1 to 4 sensors with Memosens technology If the PC does not have a sufficient number of USB jacks, there is the option of using a hub.
  • Page 26: Connecting The Cables

    Connection Memobase Plus CYZ71D Connecting the cables Connect the mini USB connector to the mini USB jack on the MemoLink. Connect the M12 connector to the M12 jack on the MemoLink. Both the flexible Memosens cable CYK20 and the Memosens process cable CYK10 can be used.
  • Page 27: Connecting In A Hazardous Area

    Memobase Plus CYZ71D Connection Connecting in a hazardous area a0018322-en Fig. 4: Connecting in a hazardous area The PC, USB cable and MemoLink may only be used in non-hazardous areas. Memosens cables and sensors with Ex approval may also be operated in a hazardous area e.g. fume cupboard.
  • Page 28: Starting The Program

    Starting the program Memobase Plus CYZ71D Starting the program Make sure that Memobase Plus has been installed on your computer as specified in the installation instructions. Make sure that MemoLink is connected via the USB port of your computer. Start Memobase Plus by clicking on the desktop icon, for example.
  • Page 29: General Program Structure

    Memobase Plus CYZ71D General program structure General program structure Here you can find some information about the general program structure: • A tab is generated for every connected MemoLink box. The tab contains information about the: – Sensor version and serial number –...
  • Page 30: Edit Fields

    General program structure Memobase Plus CYZ71D Edit fields There are edit fields at various points in the program. With these fields, you can set the desired values using the arrows. If the cursor is in front of the decimal point you only change the whole numbers with the arrow keys.
  • Page 31: Help Text

    Memobase Plus CYZ71D General program structure Help text Help text Help text is saved for many text fields. If you position the cursor over such a field, a question mark is displayed beside the cursor. Right-click to display the help text. The help text disappears as soon as you move the mouse.
  • Page 32: Status Bar

    General program structure Memobase Plus CYZ71D Status bar Current information about user administration and active error messages are displayed in the status bar. Click the error message for more detailed information and remedial measures. If user administration is activated, click "Logged in user" on the bottom left. A window opens with the following options: •...
  • Page 33: Measurement

    Memobase Plus CYZ71D Measurement Measurement The following windows are displayed in the MEASUREMENT menu item: • Main values • Secondary values • Measurement graph • Sample description • Measurement settings a0019163-en An explanatory video clip is provided on the DVD.
  • Page 34: Main And Secondary Values

    Measurement Memobase Plus CYZ71D Main and secondary values a0019134-en a0019133-en Fig. 7: Secondary values Fig. 6: Main values The main values and secondary values of the connected sensor are displayed, e.g. pH, Voltage, Temperature and Glass impedance. In the case of pH sensors, automatic temperature compensation (ATC) is enabled in the default settings.
  • Page 35: Measurement Graph

    Memobase Plus CYZ71D Measurement Measurement graph The live measured values and a graph of the measured value trends are displayed. Measurement starts automatically as soon as a sensor is connected and stops when a sensor is removed. The display can be adjusted as follows: •...
  • Page 36: Name Of The Sample

    Measurement Memobase Plus CYZ71D Name of the sample A wide range of information can be entered for the measured sample: Function Info Product Enter the name of the product. Plant Enter the name of the plant. Batch Specify the name of the batch.
  • Page 37: Measurements

    Memobase Plus CYZ71D Measurement Measurements Different settings can be made for the measurement: Function Options Info Type of measurement Options • Standard measurement: • Standard measurement Runs as long as the sensor is connected. Current • Long term measurement measured values are saved to the DB by pressing the Save button.
  • Page 38: Calibration

    Calibration Memobase Plus CYZ71D 10 Calibration 10.1 Definitions Calibration (as per 1319): A calibration is defined as a set of operations that establish the relationship between the measured value or expected value of the output variable and the related true or correct value of the measured variable (input variable) for a measuring system under specified conditions.
  • Page 39 Memobase Plus CYZ71D Calibration The Nernst equation, which is used to calculate the pH value, is a typical linear relationship: - 2.303 RT U = U pH = -lg(a ), a Activity of the hydrogen ions Raw measured value in mV Zero point (=voltage at pH 7) Relative gas constant (8.3143 J/molK)
  • Page 40: Notes On Performing A Calibration

    Calibration Memobase Plus CYZ71D 10.2.3 Delta zero point The software determines the difference between the zero points and the operating points (ISFET sensor) of the last and second-last calibration. A shift in the zero point or operating point (offset) does not alter the sensitivity of the measurement. However, if the offset is not corrected this can corrupt the measured value.
  • Page 41: Types Of Calibration

    Memobase Plus CYZ71D Calibration 10.4 Types of calibration ISFET Combin Cond. Ind. Oxygen Chlorine conductivi conductivi amp. Temperature Offset Two-point Data entry Cell constant Cell constant data entry Installation factor Air set Replace electrolyte Replace sensor cap Air 100% rH...
  • Page 42 Calibration Memobase Plus CYZ71D Offset calibration Offset calibration is particularly useful if the deviation of the pH value from a reference value, and not the absolute pH value itself, is of interest to the user. Applications for single-point cali- bration include: •...
  • Page 43: Cell Constant

    This is particularly important in the pharmaceutical industry as it is compulsory the calibration be traced back to internationally recognized standards here. To calibrate its inspection unit, Endress+Hauser uses SRM (Special Reference Material) from the US NIST authority (National Institute of Standards and Technology).
  • Page 44: Airset

    Calibration Memobase Plus CYZ71D Airset While, for physical reasons, the calibration line goes through zero in the case of conductive sensors, (a current flow of 0 corresponds to a conductivity of 0), the residual coupling between the primary coil (transmitting coil) and the secondary coil (receiving coil) must be taken into consideration and compensated for inductive sensors.
  • Page 45: Sample Slope

    Memobase Plus CYZ71D Calibration Sample slope Calibration is possible both in the medium and in air. For this purpose, you measure the raw chlorine value using a reference measurement. You use this reference value to adjust the sensor. You can either calibrate the slope or the zero point with the reference value.
  • Page 46: Performing The Calibration

    Calibration Memobase Plus CYZ71D 10.5 Performing the calibration 10.5.1 General information a0019164-en Select the sensor to be calibrated. Click CALIBRATE and select the type of calibration. Decide whether you want to perform an "As found - as left" measurement in addition to the calibration.
  • Page 47 Memobase Plus CYZ71D Calibration You have the following options after the calibration: – You can view or print out a CAL. REPORT, or export it to PDF format. – You can view or print out the CAL. RESULT, or export it to PDF format.
  • Page 48 Calibration Memobase Plus CYZ71D a0019114-en In the default setting, the function "Automatically remove reference solution from the list in the calibration menu after expiration date. " is selected. If the check box is not ticked and the reference solution continues to be used after the expiry date, a warning message is displayed.
  • Page 49 Memobase Plus CYZ71D Calibration a0019251-en Example for oxygen Ambient air, pure oxygen or sodium sulfite solution are generally available for the calibration of oxygen sensors. The creation of "ambient air" as a reference is given by way of example here for "As found - as left measurement"...
  • Page 50 Calibration Memobase Plus CYZ71D 10.5.3 As found - as left measurement The as found - as left measurement is used to document the sensor condition directly before and after the adjustment to ensure full traceability. The as found measurement is performed before cleaning and adjusting the sensor with a reference solution.
  • Page 51 Memobase Plus CYZ71D Calibration 10.5.4 Two-point calibration a0019165-en Before you can start two-point calibration, you must create at least two buffers under CALIBRATE > Reference solution management (see the "Reference solution management" section) whose values are more than 1.0 pH apart.
  • Page 52: Temperature Adjustment

    Calibration Memobase Plus CYZ71D 10.6 Temperature adjustment a0019111-en Click CALIBRATE > TEMPERATURE. Follow the instructions on the screen. You have the following options after the adjustment: – You can view or print out a CAL. REPORT, or export it to PDF format.
  • Page 53: Numeric Input

    Memobase Plus CYZ71D Calibration 10.7 Numeric input a0019112-en Click CALIBRATE > NUMERIC INPUT. Click APPLY. Follow the instructions on the screen. You have the following options after the adjustment: – You can view or print out a CAL. REPORT, or export it to PDF format.
  • Page 54: Replacing The Electrolyte Or Sensor Cap

    Calibration Memobase Plus CYZ71D 10.8 Replacing the electrolyte or sensor cap a0019113-en Follow the instructions on the screen. Endress+Hauser...
  • Page 55: Calibration Examples

    Memobase Plus CYZ71D Calibration 10.9 Calibration examples 10.9.1 Oxygen The voltage applied at the sensor by MemoLink causes polarization of the amperometric measuring system. For this reason, when MemoLink and the Memobase Plus software are switched when the sensor is attached, you must first wait for the polarization time to elapse before you can begin the calibration.
  • Page 56 Calibration Memobase Plus CYZ71D If you do not: Click START. 10. Select the medium pressure: – Process – Ambient air – Altitude Specify the process pressure [hPa], air pressure [hPa] or altitude [m]. 11. Clean the sensor before introducing it into the medium or the air.
  • Page 57 Memobase Plus CYZ71D Calibration 10.9.2 Conductivity Before the calibration, decide whether you want to perform an "As found - as left" measurement. If you do, specify a reference under CALIBRATE > Reference solution management (see "Reference solution management" section). Cell constant See the "Notes on performing a calibration".
  • Page 58: Sensors

    Sensors Memobase Plus CYZ71D 11 Sensors 11.1 Settings Information about the connected sensor is specified under SENSORS > SETTINGS. Furthermore, the associated template with the template type and name are also displayed. From the name you can see whether the template in question is a template with standard settings or a new template that has been created with modified settings.
  • Page 59 Memobase Plus CYZ71D Sensors 11.1.1 Templates All the settings which form the basis for the MEASURE and CALIBRATE main menus are specified in the template. The type of template indicates whether the template is generally used for one sensor type (e.g.
  • Page 60 Sensors Memobase Plus CYZ71D Creating a template Each new template is created on the basis of the standard settings. a0019600-en Click SAVE AS…. The Add template window is displayed. Select the Type of new template. Enter a name for the template under Name of new template.
  • Page 61 Memobase Plus CYZ71D Sensors 11.1.3 General settings You can make settings for the following points here (depends on sensor): • Operating mode • Damping temperature • Temperature compensation type 11.1.4 General limit values Operating hour limits The total operating time of the sensor and its use under extreme conditions is monitored. If the operating time exceeds the defined threshold values, the device issues a corresponding diagnostics message.
  • Page 62 Sensors Memobase Plus CYZ71D Remedial action ‣ Clean the sensor. ‣ Check the position of the sensor in the medium. ‣ Check the measuring chain. Sensor condition check Sensor condition check (SCC) monitors the electrode status and the degree of electrode aging.
  • Page 63: Sensor State

    Memobase Plus CYZ71D Sensors 11.1.6 Calibration limits You can make settings for the following points here (depends on sensor) • Delta zeropoint check on/off • Sterilization limit check on/off • Calibration timer check • Calibration validity check on/off • Delta slope check on/off 11.2 Sensor state...
  • Page 64: Sensor Information

    Sensors Memobase Plus CYZ71D You can find the following information under "Operating hours counter": • Operating hours total • Operation in hours < or > a certain temperature • Operation in hours < or > a certain voltage • Measured max. temp.
  • Page 65 Memobase Plus CYZ71D Sensors With Memobase Plus you can access the Endress+Hauser W@M portal via a direct link. This portal contains additional information and documents for your sensors. Firstly, enter your access data for the W@M portal under SYSTEM > SETTINGS > W@M Portal.
  • Page 66: Sensor Administration

    Sensors Memobase Plus CYZ71D 11.4 Sensor administration a0019120-en You can read the following information under "Sensor identification": • Name • Order code • Serial number • Sensor parameter You can specify information for the following points on the "Operating state" tab: •...
  • Page 67: Reports

    Memobase Plus CYZ71D Reports From here you can also directly select OPEN W@M PORTAL. Firstly, enter your access data for the W@M portal under SYSTEM > SETTINGS > W@M Portal. You need only do this once. 12 Reports a0019121-en In the REPORTS menu item, you can display detailed information on the MEASURE, CALIBRATION, SENSORS and REFERENCE SOLUTION menu items in table form, depending on the specific parameter.
  • Page 68 Reports Memobase Plus CYZ71D The individual reports can be: • Viewed • Printed out • Exported to PDF format • Exported to CSV format The report is always created for the data record marked blue. Furthermore, you also have the option of exporting the entire data record to CSV format.
  • Page 69: Measurement

    Memobase Plus CYZ71D Reports 12.1 Measurement a0019123-en Here you can find various items of information on the measurements made and saved. By clicking GRAPH you open a window in which you can analyze your measurements interactively. Endress+Hauser...
  • Page 70: Calibration

    Reports Memobase Plus CYZ71D 12.2 Calibration Here you can find various items of information on the calibrations made and saved. 12.3 Sensors Here you can find various items of information saved about the sensors. 12.4 Reference solution Here you can find various items of information saved about the reference solutions.
  • Page 71 Memobase Plus CYZ71D Reports a0019124-en Endress+Hauser...
  • Page 72: Language / Language

    Language / Language Memobase Plus CYZ71D 13 Language / Language a0017299-en The language of the user interface can be easily changed if users who speak another language would like to work with the database. The language in which the reports appear can also be changed.
  • Page 73: Setup

    Memobase Plus CYZ71D Setup 14 Setup a0019122-en You can configure the following points here: • SETTINGS • AUDIT TRAIL • USER • LICENSE Endress+Hauser...
  • Page 74: Settings

    Setup Memobase Plus CYZ71D 14.1 Settings 14.1.1 Database Memobase Plus is based on a client-server architecture and allows multiple client access. All the data are saved centrally in a database. Alternatively they can also be saved locally. The software can be combined with the following databases: •...
  • Page 75 Memobase Plus CYZ71D Setup For versions with pharmaceutical compliance Please note that responsibility for fully implementing the requirements of FDA 21 CFR Part 11 lies with you. The "Pharmaceutical compliance" order option helps you meet the criteria of this standard. To comply with the stricter documentation and safety requirements of FDA21 CFR Part 11, it is necessary to activate user administration including "Password protection compliant to FDA21 CFR Part 11".
  • Page 76 Setup Memobase Plus CYZ71D 14.1.5 W@M portal Under SYSTEM > SETTINGS > W@M Portal you can access the Endress+Hauser W@M portal. This portal contains additional information and documents for your sensors. To set up W@M access: Enter your W@M user ID.
  • Page 77: Audit Trail

    Memobase Plus CYZ71D Setup 14.2 Audit trail The audit trail is needed for traceability purposes. It constitutes a chronological account in table form of all the actions and events that have occurred. The most recent action is listed at the top.
  • Page 78: Users

    Setup Memobase Plus CYZ71D 14.3 Users To protect Memobase Plus against unauthorized or undesired modifications, you can allow database access only to certain users who have a database password, and assign user roles to these users. You can use the following user roles:...
  • Page 79 Memobase Plus CYZ71D Setup 14.3.1 Adding users Proceed as follows to create a new user: Click SYSTEM > USER > NEW. The Create new user dialog box is displayed. Enter the User ID, Name and Password . You can define the requirements for the password under SYSTEM > SETTINGS > User administration .
  • Page 80: License

    14.3.4 Forgotten your password If you have forgotten your password, please contact a colleague with "Expert / Service engineer" as his/her user role, your system administrator or Endress+Hauser Service. 14.3.5 Settings Here you can make the same settings as under SYSTEM > SETTINGS > User administration.
  • Page 81: Help

    The following are the most important accessories available at the time this documentation was issued. For accessories not listed here, please contact your service or sales office. 16.1 Accessories for Memobase Plus CYZ71D Order No. 71163002 Kit CYZ71D MemoLink for Memosens (incl. USB cable) 71162980 Kit CYZ71D USB cable 16.2 Measuring cable...
  • Page 82: Technical Data

    Technical data Memobase Plus CYZ71D 17 Technical data 17.1 Input 17.1.1 Input type Memosens port : M12 socket 17.1.2 Measured variables All sensors with an inductive Memosens plug-in head are suitable for connection (pH/ORP, conductive conductivity, dissolved oxygen and chlorine) as well as inductive conductivity with fixed cable and M12 connector.
  • Page 83: Performance Characteristics

    Memobase Plus CYZ71D Technical data 17.4.2 Power supply • 5 V DC via USB • Low power mode: max. 100 mA as per USB specification 2.0 17.5 Performance characteristics 17.5.1 Measured error --> Documentation for the connected sensor MemoLink only transmits data digitally so no measured data can be corrupted. The measuring signal is converted to digital data in the sensor, which means that MemoLink, the cable or PC software do not affect the measured values.
  • Page 84: Operating Principles

    Operating principles Memobase Plus CYZ71D 18 Operating principles 18.1 pH measuring technology The pH value is measured potentiometrically to accurately measure aqueous and non-aqueous solutions. The electrode system consists of a glass electrode (pH electrode) and a reference electrode. The difference in voltage E between these two electrodes is measured with high impedance and is a function of the pH value of the solution.
  • Page 85 Memobase Plus CYZ71D Operating principles The glass electrode The glass electrode has a "pH-sensitive" membrane that forms a gel layer in water. The relatively small H ions can nest in this gel layer and the larger negatively charged ions remain in the solution.
  • Page 86 Operating principles Memobase Plus CYZ71D The reference electrode The reference electrode provides a stable potential compared to the working electrode. In industrial instrumentation, only the silver/silver chloride system (Ag/AgCl) with KCl solution is important. A silver wire coated with silver chloride responds to the chloride ion activity of the surrounding solution.
  • Page 87 Memobase Plus CYZ71D Operating principles Combination electrode To make it more easy to use, the two electrode types are often combined in an electrode system. An electrode system where the reference silver wires of the glass electrodes and reference electrodes are the same, is called a symmetric electrode system. If both electrode versions are combined in one model, this is called a combination electrode.
  • Page 88 Operating principles Memobase Plus CYZ71D 18.1.2 pH value and temperature The electrode slope (mV/pH) depends on the temperature. At a solution temperature of 25 °C (77 °F), the electrode returns a voltage of 59.16 mV per pH difference between the inner buffer and the solution.
  • Page 89 Memobase Plus CYZ71D Operating principles This effect is corrected with automatic or manual temperature compensation in the transmitter. Ideally, the various Nernst lines (isotherms) of different temperatures cut at one point which is known the isotherm intersection point. This is at 0 mV = pH 7 for electrodes with inner buffer pH 7.
  • Page 90 Operating principles Memobase Plus CYZ71D 18.1.3 ISFET sensors In contrast to glass electrodes, ISFET sensors use a pH-sensitive semi-conductor to determine the pH value. Ion-selective field effect transistors are based on an MOS transistor arrangement. Here the gate is replaced by a tantalum pentoxide layer that is sensitive to protons. The electrostatically...
  • Page 91: Dissolved Oxygen

    Memobase Plus CYZ71D Operating principles 18.2 Dissolved oxygen 18.2.1 Basic principles The example of air is useful in explaining oxygen partial pressure. Partial pressure is the portion of oxygen in air which, together with the other gases such as nitrogen, inert gases and carbon dioxide, makes up the total pressure of the air.
  • Page 92 Operating principles Memobase Plus CYZ71D a0015947 Fig. 21: Oxygen content in water in relation to the temperature Maximum solubility is reached when the oxygen partial pressure in the water is the same as in the atmospheric layer above it. The concentration of oxygen in the water is then identical to the solubility.
  • Page 93 Memobase Plus CYZ71D Operating principles Oxygen saturation (SAT in %) describes, as a percentage, the ratio of the actual partial pressure of oxygen to the theoretical value expected in humid air. Oxygen partial pressure is 212 hPa at an ambient pressure of 1013 hPa (at sea level). This means an oxygen content of 20.95 %. This value is what practitioners refer to as 100 % saturation.
  • Page 94 Operating principles Memobase Plus CYZ71D a0015941 Fig. 22: Design of a two-electrode sensor Direct current Electrolyte chamber Anode Cathode Medium Membrane • Cathode reaction + 2H O + 4e • Anode reaction 4Ag + 4Br 4AgBr + 4e A feature of two-electrode sensors is that, while the oxygen is reduced to hydroxide ions and electrons at the cathode, at the anode, bromide or chloride ions are deposited from the electrolyte as silver bromide or silver chloride.
  • Page 95 Memobase Plus CYZ71D Operating principles electrode. An internal regulating circuit keeps the working electrode at constant potential. The need for a service at the sensor is thus halved. a0015942 Fig. 23: Design of a three-electrode sensor Direct current Electrolyte chamber...
  • Page 96 Operating principles Memobase Plus CYZ71D 18.2.3 Calibration The amperiometric and optical oxygen senors must be calibrated to ensure that they supply accurate measured values. The gradient of an oxygen sensor can, in principle, be calibrated in three ways: • in an atmosphere saturated with water vapor •...
  • Page 97 Memobase Plus CYZ71D Operating principles a0015947 Fig. 24: Water vapor in the atmosphere in relation to the temperature This factor is used in the "water-saturated air" ("air 100 %rF") calibration method. In this case, the proportion of water vapor is calculated based on the altitude and the temperature so that information is available about the actual oxygen partial pressure present.
  • Page 98 Operating principles Memobase Plus CYZ71D How high is the partial pressure of oxygen at sea level at 35 °C? 956.79 hPa = 0.2095 oxygen_estimated = 200.44 hPa oxygen_estimated If this method is to work correctly, the sensor to be calibrated must be placed in close proximity to a water surface or in the gas compartment of a vessel which is partially filled with water.
  • Page 99: Electrolytic Conductivity

    Memobase Plus CYZ71D Operating principles hermetically-sealed, this remains the case for more than 24 hours approximately. Air penetration shortens this time. It is worthwhile to take a look at the behavior of the sensor signal prior to calibration of the...
  • Page 100 Operating principles Memobase Plus CYZ71D a0018773 Fig. 25: Measuring principle It is common to calculate material-dependent conductivity (Greek kappa) with the aid of the cell constant k which describes the geometry of the measuring arrangement: ⋅  = G The cell constant k is small for large electrode surfaces and a small electrode separation distance and vice versa.
  • Page 101 Memobase Plus CYZ71D Operating principles 18.3.2 Conductivity sensors The choice of conductivity sensor is mainly based on the measuring range required. Sensors with a cell constant k of 0.01 cm or 0.1 cm are used for applications in demineralized water or ultrapure water.
  • Page 102 Operating principles Memobase Plus CYZ71D a0018779 Fig. 27: Structure of inductive sensors The advantages of inductive sensors are: • Insensitive to contamination • No upward measuring range restriction due to the polarization effect. This occurs with conductive sensors in higher conductivities if charge clouds form in front of the electrodes due to the current density and thereby screen the electrodes.
  • Page 103 Memobase Plus CYZ71D Operating principles 18.3.3 Temperature influence quantity Like many other measured variables, electrolytic conductivity in liquids depends on the temperature: the mobility of the ions is affected by the temperature. In the case of weak electrolytes (i.e. electrolytes that only partially dissociate), the number of ions depends on the temperature.
  • Page 104 Operating principles Memobase Plus CYZ71D Linear compensation The change in conductivity is taken as constant at different temperatures, i.e. is constant with regard to temperature and concentration. The value can be entered directly in the device. Linear compensation is particularly suitable for a restricted medium temperature range. The numerical value is taken from literature on the subject or is determined experimentally.
  • Page 105 Memobase Plus CYZ71D Operating principles Temperature compensation using user tables Users can enter tables for their own special media. The temperature coefficients are entered depending on the temperature or also depending on the temperature and the (compensated) conductivity (two or three-dimensional tables).
  • Page 106 Operating principles Memobase Plus CYZ71D 18.3.4 Determining the concentration using the conductivity Since the number of ions in the solution determine the conductivity, conductivity measuring systems are often used to directly display the concentration of acids, alkalis or salts. The conductivity first increases quickly with increasing ion concentration. However, at higher concentrations the ions obstruct one another.
  • Page 107 Memobase Plus CYZ71D Operating principles CIP (Clean In Place) liquids with common concentrations are always to the left of the maximum and can be easily measured. A number of concentration algorithms are saved in the devices, depending on how the devices are equipped.
  • Page 108 Operating principles Memobase Plus CYZ71D In the end, you should have measuring data which appear as illustrated in the following two graphics. a0018886 Fig. 31: Example for measuring data in the case of variable temperature  Conductivity Measuring point Concentration...
  • Page 109 Memobase Plus CYZ71D Operating principles 18.3.5 Limit values as per USP (United States Pharmacopeia) In the case of conductive sensors, Memobase Plus has a function for monitoring WFI water (Water for Injection) as per the standard USP (United States Pharmacopeia), Part 645.
  • Page 110 This is particularly important in the pharmaceutical industry as it is compulsory the calibration be traced back to internationally recognized standards here. To calibrate its inspection unit, Endress+Hauser uses SRM (Special Reference Material) from the US NIST authority (National Institute of Standards and Technology).
  • Page 111 Memobase Plus CYZ71D Operating principles the following diagram. A modified cell constant is entered by multiplying by the installation factor, or the installation factor can be entered as a separate variable. a0018892-en Fig. 34: Distance between measuring cell and pipe wall...
  • Page 112 Operating principles Memobase Plus CYZ71D 1.40 1.20 1.00 0.80 a [mm] 0.20 0.39 0.59 0.79 0.98 a [inch] a0005441 Fig. 35: Installation factor f depending on the distance a to the pipe wall Calibration and adjustment of temperature measurement As the electrolytic conductivity is subject to influence from temperature, it makes sense to also calibrate, and where necessary adjust, the temperature sensor, which is integrated in the sensor, together with Memobase Plus.
  • Page 113: Index

    Memobase Plus CYZ71D Index Accessories ......81 Identification Adjustment......38 Nameplate.
  • Page 114 Memobase Plus CYZ71D Reference solution management ... 47 Zero point sample ..... . 45 Replace electrolyte .
  • Page 115 Memobase Plus CYZ71D Endress+Hauser...
  • Page 116 71227351 www.addresses.endress.com...

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