YOKOGAWA PH71 User Manual
  1. Manuals
  2. Brands
  3. YOKOGAWA Manuals
  4. Measuring Instruments
  5. PH71
  6. User manual

YOKOGAWA PH71 User Manual

Personal ph meter
Hide thumbs Also See for PH71:
Table of Contents

Advertisement

Quick Links

Download this manual
User's
Manual
Model PH71
Personal pH Meter
IM 12B03D01-01E
IM 12B03D01-01E
4th Edition

Advertisement

Table of Contents
loading

Related Manuals for YOKOGAWA PH71

Summary of Contents for YOKOGAWA PH71

  • Page 1 User’s Manual Model PH71 Personal pH Meter IM 12B03D01-01E IM 12B03D01-01E 4th Edition...
  • Page 2 Preface Preface Thank you for purchasing the Model PH71 Personal pH Meter. Please read this manual thoroughly before using the meter. The related documents (User's Manual) are as follows. IM 12B03D01-01E Model PH71 Personal pH Meter (this manual) IM 12B03D01-02E Model PH71 Personal pH Meter Quick Manual * the “E”...
  • Page 3 Preface Liquid Crystal Display (LCD) Characters On the LCD alphanumeric characters are displayed as follows. Alphabet Display Alphabet Display Numerals Display All display segments F00.ai Note Regarding Panels Shown in this Manual: Panels shown in this manual should be regarded as examples. Actual panel format may vary depending on parameter settings and on type of connected sensor.
  • Page 4 In addition, performance deterioration of the sensor caused by the operating environment mentioned above is not considered to be a defect. Yokogawa cannot carry out repairs in such a case so please replace the sensor.
  • Page 5 Do not dispose in domestic household waste. When disposing products in the EU, contact your local Yokogawa Europe B. V. office. Authorised Representative in EEA The Authorised Representative for this product in EEA is Yokogawa Europe B.V. (Euroweg 2, 3825 HD Amersfoort, The Netherlands). IM 12B03D01-01E...

  • Page 6: Table Of Contents

    1. Outline ........................ 1-1 1.1 Features .......................... 1-1 1.2 Specifications ........................1-2 1.3 When You Receive the PH71 Meter Package ..............1-4 1.4 PH71 Meter Kit ........................ 1-5 1.5 PH71 Meter — Part Names and Functions ..............1-6 1.6 Sensors — Types, Part Names and Functions............... 1-7 1.7 Spare Parts ........................
  • Page 7 Contents Revision Record ......................i Toc-2 IM 12B03D01-01E...

  • Page 8: Outline

    With its waterproof construction, the PH71 can be used outdoors in any weather and will not be damaged if it accidentally falls into water (tap water, etc.). However, since the PH71 is not hermetically sealed, do not leave it in water for a long time or pour chemical solutions on it.

  • Page 9: Specifications

    1. Outline Specifications Measurement: Hydrogen ion concentration (pH) of solution Measuring range: 0 to 14 pH* Temperature; 0 to 80°C* (or 0 to 100°C* Resolution: 0.01 pH Temperature; 0.1°C Repeatability (without sensor): ±0.01 pH Accuracy: Temperature; ±0.7°C (0 to 70°C) ±1°C (above 70°C) Display: Digital LCD...
  • Page 10 1. Outline EMS (Immunity): EN 61326-1 Table 2 (For ise in industrial locations Performance Test Item Test Specification Basic Standard Criteria* Electrostatic 4 kV (contact) IEC 61000-4-2 discharge 8 kV (air) 80 to 1000 MHz, 10 V/m (unmodulated) 80% AM (1 kHz) RF amplitude 1.4 to 2.0 GHz, modulated...

  • Page 11: When You Receive The Ph71 Meter Package

    Confirm that you received all package components of the PH71 meter you ordered referring to the Model and Suffix Code and the item list in Section 1.4, “PH71 Meter Kit.” Carefully inspect the meter and sensor, referring to Section 1.5, “PH71 Meter —...

  • Page 12: Ph71 Meter Kit

    Global except South Korea and Malaysia (with batteries) None South Korea and Malaysia (without batteries) *2 *1: PH71-60 and PH71-61 comform to the Japanese Measurement Act. Its hardware is the same as “PH71-00” or “PH71-21” respectively. *2: For South Korea and Malaysia (-NB), batteries are not attached.

  • Page 13: Ph71 Meter - Part Names And Functions

    1. Outline PH71 Meter — Part Names and Functions O-ring Sensor cable connector Connection to a dedicated pH sensor. Hand strap attachment points Display pH and temperature simultaneously. Battery box cover fixing screw Keypad Name plate S2.0 E000001 2014. F010501.ai...

  • Page 14: Sensors - Types, Part Names And Functions

    1. Outline Sensors — Types, Part Names and Functions Sensors available for use with the Model PH71 Personal pH Meter are: general- purpose pH sensors (KCl replenish-free and KCl refillable types), needle type pH sensor, and test tube size pH sensor. Check the Model and Suffix Code on the name plate to identify the type of your sensor.

  • Page 15: Spare Parts

    2 O-rings for connector 1 wetting cap F010801.ai O-rings and gaskets are important parts to ensure that the PH71 meter is water resistant. Replace these parts as required. Refer to Section 6.7, “Storage and O-ring/ Gasket Replacement” for replacement. IM 12B03D01-01E...

  • Page 16: Preparation

    2. Preparation 2. Preparation Installing the Batteries Install the batteries first. In South Korea and Malaysia, primary battery is limited by regulations. Please use batteries with the authorized certification mark for each country. CAUTION Select a relatively moisture-free location when installing batteries in the meter. When installing batteries, observe correct polarity (battery orientation).

  • Page 17: Connecting The Sensor Cable

    Sensors for the PH81 or PH82 meters can be connected. When used in conjunction with the PH71 meter, however, water resistance is not guaranteed. This is due to the different construction of the connector cover. (1) Pull the waterproof cover along the sensor cable away from the connector to expose the locknut.

  • Page 18: Wetting Cap

    2. Preparation Setting Procedure POWER After installing the batteries, press and hold key for at least one second. All LCD segments appears momentarily and then the date setting display starts automatically. Set year, month, day, hours, and minutes following the flowchart below. Note: If you attempt to abort the setting procedure before completing, the meter will beep three times and reject the attempt.

  • Page 19: Manual Temperature Setting

    Section 5.3 (2), “Manual temperature setting (M.tP) panel.” Temperature compensation is performed based on a temperature shown on the display of the PH71 meter. If a temperature shown on the display is different from the actual temperature of the sample being measured, the displayed measured value may not be true.

  • Page 20: Measurement

    50°C. Also, do not use the meter in strongly corrosive solutions, such as a solution containing hydrofluoric acid. (4) Remove stains from the PH71 meter body using a soft cloth or tissue. If necessary, use a neutral detergent.

  • Page 21: Measurement Procedures

    3. Measurement Measurement Procedures Immersing the sensor Immerse the sensor so that the protective cover part goes under the sample solution level. The sensor does not need to be immersed deeply. When using a KCl refillable type sensor, the filling solution level must be above the level of solution being measured.

  • Page 22: Measurement Display Panel

    3. Measurement Measurement Display Panel When immersing the sensor in a sample solution, a measured pH value will be shown on the display. There are three types of measurement display panels: the standard, calendar, and clock display panels. Use key to cycle through these display MEAS panels.
  • Page 23 3. Measurement (2) Data storage If the key is pressed during measurement, mark starts flashing. DATA F/ENT Press the key, then currently measured data can be stored in nonvolatile memory. Data stored are measured pH, measured temperature, date and time. Up to 300 data including individually deleted data can be stored.

  • Page 24: Calibration

    Calibration using standard solutions means to measure the pH value of a certified standard solution and to adjust the pH meter so it reads the same value as the certified value of the standard solution. The PH71 meter can be calibrated automatically or manually.

  • Page 25: Automatic Calibration

    1-point calibration twice using the same standard solution. Automatic Calibration In automatic calibration the Model PH71 Personal pH Meter automatically recognizes standard solutions being used and calibrates itself using values of Table 4.1. Two types of standard solutions are preprogrammed: NIST (solutions prepared in accordance with Japanese standards, factory default) and US (solutions prepared in accordance with the U.S.
  • Page 26 4. Calibration Before Automatic Calibration Make sure that the correct type of standard solutions to be used for automatic calibration has been selected (refer to Section 5.3 (9), “Standard solution setting (Std) panel”). Procedure Example 1: 2-point calibration using pH 7 and pH 4 standard solutions Water Wait until POWER...

  • Page 27: Manual Calibration

    4. Calibration The last two calibration results are saved in the meter. Therefore, for 1-point calibration, perform a 1-point calibration twice using the same standard solution, or initialize calibration parameters (refer to Section 5.3 (10), “Initialize calibration parameters (I.CP) panel”) before performing a 1-point calibration. Example 2: Calibration of a sensor without a built-in temperature element* using a pH 7 standard solution Needle type or test tube size pH sensor...
  • Page 28 4. Calibration Note: Although manual calibration can be performed using standard solutions the same as the ones preprogrammed for automatic calibration, it only makes the procedure more complicated. When using these standard solutions, automatic calibration should be generally performed. Precautions (1) The difference between the pH values of two standard solutions to be used for 2-point calibration must be at least 0.7 pH.
  • Page 29 4. Calibration For 2-pont calibration, continue the procedure following the dotted line. When using a sensor without a built-in temperature element (needle type or test tube size pH sensor), enter the temperature of standard solution following the procedure described in Section 4.1, Example 2. IM 12B03D01-01E...

  • Page 30: Keypad And Display Functions

    5. Keypad and Display Functions 5. Keypad and Display Functions There are eight membrane keys on the keypad of the Model PH71 Personal pH Meter. The following key functions are provided. • Displaying a pH value and temperature • Displaying a pH value, date and time •...

  • Page 31: Display Items

    5. Keypad and Display Functions : DATA key DATA When pressed during measurement, mark flash and the currently displayed measured pH value and temperature are held temporarily. Pressing F/ENT key while mark is flashing, will store the held data in memory. After the data is stored successfully, the meter returns to measurement mode automatically.
  • Page 32 • deposits are present on the electrode (check is performed during calibration). If deposits are present, clean the sensor (see Section 6.2); or, • calibration is performed improperly. If you performed an incorrect calibration procedure, initialize the calibration parameters and calibrate the PH71 again (see Section 7.4). IM 12B03D01-01E...

  • Page 33: Function Mode

    5. Keypad and Display Functions Function Mode Outline Various functions are supported by function mode. Press key while the meter F/ENT is in measurement mode to move to function mode. Note: The last selected and executed item is displayed when you move to function mode. Use keys to cycle through the items listed in Table 5.1 in that order.
  • Page 34 5. Keypad and Display Functions Operating procedures on each panel are described below. (1) Display stored data (dAt) panel Shows stored data on the LCD with mark. When you access this panel, the last stored pH value and temperature will be displayed with the data number flashing at the lower left of the display.
  • Page 35 5. Keypad and Display Functions F/ENT to display other data Day and month data item was stored Year data item was stored Stored measurement data DATA DATA Latest data DATA "Delete stored data" panel Time data item was stored DATA F/ENT DATA F/ENT...
  • Page 36 5. Keypad and Display Functions to set F/ENT to confirm F/ENT F050302.ai (3) Delete all stored data (dEL.A) panel Used to delete all stored data. Press key on the flashing “dEL.A” panel. F/ENT will be flashing. Use keys to select .
  • Page 37 5. Keypad and Display Functions (5) Time setting (tIME) panel Used to set the time — hour (24-hour format) and minute in this order. Use keys to set the time and press key to confirm each entry. F/ENT Hour setting (24-hr clock) Minute setting F/ENT F/ENT...
  • Page 38 5. Keypad and Display Functions F/ENT Hour setting (24-hr clock) alarm sounds F/ENT at preset time every day F/ENT Minute setting alarm sounds at preset time from Monday to Friday alarm sounds once at preset time F050306.ai (7) Set Auto Power Off time (A.oFF) panel Used to set the automatic power off time.
  • Page 39 5. Keypad and Display Functions (8) Set beep on/off (bZ.o) panel The beep sound on key press can be enabled/disabled in this panel. Use keys F/ENT to select on or off and press key to confirm. Note that this beep setting does not affect the alarm sounding (see Item (6)).
  • Page 40 5. Keypad and Display Functions (11) Set temperature unit (tP.U) panel Used to select the temperature unit: Celsius (°C) or Fahrenheit (°F). Use keys to select the desired temperature unit and press F/ENT key to confirm. F/ENT to toggle F/ENT to confirm F050311.ai (12) Check version number (VEr) panel...
  • Page 41 5. Keypad and Display Functions F/ENT to toggle proceed F/ENT to cancel F/ENT to execute (may not appear if deleted data amount is small) After a few seconds F050313.ai 5-12 IM 12B03D01-01E...

  • Page 42: Maintenance

    6. Maintenance 6. Maintenance For Optimum Meter Performance The Model PH71 Personal pH Meter is simple to operate, but is a precision instrument. To ensure accurate results from the meter, the following precautions should be observed. Flow Diagram Measurement Calibration...
  • Page 43 6. Maintenance CAUTION Do not apply physical shock or excessive force to the glass sensor, or it may break. Do not rub the glass membrane strongly, or it may be damaged or break. Suspended Solids, Adhesive Material, Microorganisms, Greasy Substances, etc. Dirt or deposits on the glass electrode, liquid junction or temperature element should be removed.

  • Page 44: Sensor Replacement

    6. Maintenance Sensor Replacement Since a pH sensor undergoes chemical changes with time, its performance deteriorates gradually. Under normal operating conditions a sensor can be used for one or two years. Sensor deterioration, however, speeds up depending on the nature of a sample solution, e.g., a high temperature solution.

  • Page 45: Cleaning And Drying Connectors

    6. Maintenance Cleaning and Drying Connectors Deteriorated insulation between connector pins can cause inaccurate readings. To remove stains and/or moisture that may cause deteriorated insulation, clean the connector with a dry cloth or a cloth moistened with anhydrous alcohol. If necessary, use a dryer.

  • Page 46: Storage And O-Ring/Gasket Replacement

    O-ring from staining. Contamination may cause deteriorated insulation of connectors or poor water resistance by the O-ring. (3) Do not place any object on top of the sensor or on the top of the PH71 meter. Attach wetting cap containing cotton wad moistened with a few drops of water.
  • Page 47 Install the gasket on the groove on the battery box so the raised part fits in place as shown below. The gasket is symmetrical right to left and front to back. Gasket PH71 meter top Raised part F060702.ai IM 12B03D01-01E...

  • Page 48: Troubleshooting

    (1) Improper maintenance or usage (2) Expired consumables (3) Failure If any trouble occurs, determine the cause and take corrective actions referring to Section 7.2. If the trouble cannot be fixed, contact your nearest Yokogawa sales office. ● Unstable reading Symptom ●...

  • Page 49: Error Messages, Possible Causes, And Corrective Actions

    7. Troubleshooting Error Messages, Possible Causes, and Corrective Actions Table 7.1 Error Message Error Message*1 Description Occurrence Err1 Unstable input emf Err2 Abnormal asymmetry potential During calibration Err3 Abnormal slope or calibration temperature Err4 Out of measuring range Err5 Out of temperature measuring range During measurement Err6 Meter electronics failure...
  • Page 50 (3) Err3 Abnormal slope or calibration temperature Appears during calibration. In the Model PH71 Personal pH Meter standard solution data (NIST and US) are preprogrammed. During automatic calibration the meter recognizes standard solutions being used based on these data. If standard solutions other than the preprogrammed ones are used, an Err3 message will appear.
  • Page 51 (4) Err4 Out of measuring range Appears during measurement. The Model PH71 Personal pH Meter can measure the pH value of a solution in the range of 0 to 14 pH. If the pH value of the solution being measured is significantly outside this range (-2 pH or lower and 16 pH or higher), an Err4 message will appear.

  • Page 52: Causes Of Abnormal Measured Values

    If the mark remains even though there is no problem with the sensor, the calibration parameters may be incorrect. Initialize the calibration parameters to the slope of 1.000 and asymmetry potential of 0.0 mV (see Section 5.3(10)). Then calibrate the PH71. •...
  • Page 53 7. Troubleshooting If it appears even though a sensor with a built-in temperature element is used, the temperature measuring circuit may have broken. In this case the meter performs temperature compensation assuming that the solution temperature is 25°C. Therefore, the bigger the difference between the actual temperature of the solution and 25°C, the bigger the error between the displayed measured value and the true value.

  • Page 54: Technical Information

    8. Technical Information 8. Technical Information Measurement Principle of pH Meter (Glass Electrode Method) A pH meter makes use of the potential difference developed between the two sides of a thin glass membrane that separates two solutions with different pH. Figure 8.1 shows the schematic diagram of the measurement principle.

  • Page 55: Relationship Between Emf Of Glass Membrane And Ph Value

    8. Technical Information Relationship between EMF of Glass Membrane and pH Value The relationship between the potential difference (electromotive force) developed across the glass membrane and the pH value had been studied and the theoretical values were determined. Actual values, however, do not match the theoretical values due to manufacturing variations or deterioration with time.
  • Page 56 8. Technical Information In the equation, pH is the pH buffer solution filled in the glass electrode so the pH should be constant. Using a solution (pH standard solution) with known pH as pH a certain temperature, the relationship between millivolt and pH can be determined, thereby the pH can be directly derived from the membrane potential difference, as shown in Figure 8.3.

  • Page 57: Temperature Compensation

    Figure 8.4. Measurement without temperature compensation will result in measured pH values including errors as shown in Table 8.2. The PH71 meter automatically modifies the calibration line according to the temperature measured by the temperature element incorporated in an electrode (except needle type and test tube size pH sensors).

  • Page 58: The Asymmetry Potential

    8. Technical Information Table 8.2 Deviations from True Values in Measurement without Temperature Compensation Temp.(°C) 0.50 0.10 0.00 -0.30 -0.70 -1.11 0.34 0.07 0.00 -0.20 -0.47 -0.74 0.17 0.03 0.00 -0.10 -0.23 -0.37 0.00 0.00 0.00 0.00 0.00 0.00 -0.17 -0.03 0.00 0.10...
  • Page 59 8. Technical Information Acid error Theoretical value EMF at pH 7 12 pH Slope difference Alkaline error F0805.ai Figure 8.5 EMF Characteristics of Glass Electrode 3mol/L-Na + Solution temperature at 25°C 3mol/L-K + 3mol/L-NH Test solution pH F0806.ai Figure 8.6 Ion Type vs Alkaline Error 3mol/L-Na Solution temperature...

  • Page 60: The Acid Error

    Acid Type vs Acid Error Calibration Calculation The PH71 meter is calibrated at 2 points using 2 standard solutions. The first calibration is done so a certain line is drawn through the calibration point (Figure 8.9). The second calibration is done so a line is drawn through the first and second calibration points (Figure 8.10).

  • Page 61: Wetted Part Materials Of Sensors

    8. Technical Information Second calibration point Theoretical line pH7, 0mV pH14 First Asymmetry potential calibration point Calibration line (slope) F0810.ai Figure 8.10 Calibration at Second Point Wetted Part Materials of Sensors • General pH Sensors Polypropylene resin (sensor body, protective cover) Glass (glass electrode, temperature element protective tube) Ceramics (liquid junction) Silicon rubber (sensor seal)

  • Page 62: Appendix

    Appendix Appendix Key-Operation Flow Chart (for reference) Typical screens are shown. Refer to the corresponding section in the body of the manual for details. ● When turn on power Toggle display type POWER First time used, or MEAS after replace batteries F/ENT MEAS F/ENT...
  • Page 63 Appendix ● Function Mode Manual temperature Display stored data setting F/ENT F/ENT F/ENT F/ENT DATA DATA DATA DATA F/ENT F/ENT F02.ai App-2 IM 12B03D01-01E...
  • Page 64 Appendix ● Function Mode Date setting Time setting Delete all stored data Alarm time setting Set Auto Power Off time F/ENT F/ENT F/ENT F/ENT F/ENT F/ENT F/ENT F/ENT F/ENT F/ENT F/ENT F/ENT F/ENT F/ENT ● Switching to Function Mode Measurement status ●...
  • Page 65 Appendix ● Function Mode Standard solution Initialize calibration Set beep on/off Set temperature unit setting parameters F/ENT F/ENT F/ENT F/ENT F/ENT F/ENT F/ENT F/ENT ● Function Mode Check version Defrag memory number F/ENT F/ENT F/ENT F04.ai App-4 IM 12B03D01-01E...
  • Page 66 Appendix ● Calibration Automatic calibration & Manual calibration (2-point calibration) Measurement Auto calibration Auto calibration Auto calibration in progress status is complete F/ENT Manual calibration Prompting F/ENT F/ENT Manual calibration is complete F/ENT Automatic calibration for needle type or test tube size pH sensor Measurement Auto calibration status...
  • Page 67 Appendix App-6 IM 12B03D01-01E...
  • Page 68 Revision Record Manual Title : Model PH71 Personal pH Meter Manual Number : IM 12B03D01-01E Edition Date Remark (s) Mar. 2020 Change of accessories, deletion of optional accessories, move MSDS (SDS) to site, revision of specifications, etc., full review Aug. 2009 Change of information on EMC compliance: P.1-2 Apr.

Table of Contents