User’s Manual Model PH72 Personal pH/ORP Meter IM 12B03D02-01E IM 12B03D02-01E 3rd Edition
Preface Preface Thank you for purchasing the Model PH72 Personal pH/ORP Meter. Please read this manual thoroughly before using the meter. The following symbol marks are used for safety precautions in this manual. WARNING : CAUTION : Indicates that serious injury may result, if the user fails to follow instructions. Indicates that minor injury to personnel, or damage to the equipment, may result if the user fails to follow instructions.
Preface Liquid Crystal Display (LCD) Characters On the LCD alphanumeric characters are displayed as follows. Alphabet Display Alphabet Display Numerals A N 0 B O 1 C P 2 D Q 3 E R 4 F S 5 G T 6 H U 7 I V 8 9 J W K X L Y M Z Display All display segments F00.EPS 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.
Preface Warranty and Service Yokogawa products and parts are guaranteed to be free from defects in workmanship and materials under normal use and service for a period of (typically) 12 months from the date of shipment from the manufacturer. Individual sales units may offer different warranty periods, so the original purchase order should be consulted for the conditions of sale.
Contents CONTENTS Preface ...................................................................................................................... 1-1 1. Outline ................................................................................................................. 1-1 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 Features ......................................................................................................................... Specifications ......................................................
Contents 9.3 Temperature Compensation .......................................................................................... 9-4 9.4 The Asymmetry Potential .............................................................................................. 9-5 9.5 The Alkaline Error .......................................................................................................... 9-6 9.6 The Acid Error ...................................................................................................
Contents 6 IM 12B03D02-01E
1. Outline 1. Outline The Model PH72 Personal pH/ORP Meter is a highly accurate, portable pH meter for laboratory and field application. With its self-diagnostic function, the PH72 provides precise measurement of pH and ORP (oxidation-reduction potential). Measurement results can be stored and stored data can be checked on the meter display any time.
1. Outline 1.2 Specifications pH: 0 to 14 pH*1 ORP: -2000 to 2000 mV Temperature: 0 to 1008C*2 Resolution: pH: 0.01 pH ORP: 0.1 mV (-199.9 to 199.9 mV) 1 mV (-2000 to -200 mV and 200 to 2000 mV) Temperature: 0.18C Repeatability (without sensor): pH: 60.01 pH 61 digit ORP: 61 mV 61 digit Accuracy (Temperature): 60.
1. Outline 1.3 When You Receive the PH72 Meter Package Confirm that you received all package components of the PH72 meter you ordered referring to the Model and Suffix Code and the item list in Section 1.4, “PH72 Meter Kit.” Carefully inspect the meter and sensor, referring to Section 1.5, “PH72 Meter — Part Names and Functions” and Section 1.6, “Sensors — Types, Part Names and Functions.” Particular attention should be taken: • Not to lose a wetting cap attached on the sensor tip.
1. Outline 1.4 PH72 Meter Kit 1 Instrument Card 2 6 3 Quick Manual 5 4 No.
1. Outline 1.5 PH72 Meter — Part Names and Functions O-ring Sensor cable connector Connection to a dedicated pH (ORP) sensor. Hand strap attachment points Display pH (mV) and temperature simultaneously. Battery box cover fixing screw Keypad PERSONAL pH/ORP METER MODEL PH72 STYLE S1.0 No. Name plate E000001 2004. F010501.
1. Outline 1.6 Sensors — Types, Part Names and Functions Sensors available for use with the Model PH72 Personal pH/ORP Meter are: generalpurpose pH sensors (KCl replenish-free and KCl refillable types), needle type pH sensor, test tube size pH sensor, and KCl refillable type ORP sensor. Check the Model and Suffix Code on the name plate to identify the type of your sensor. Example of Name Plate MODEL PH72SN STYLE SUFFIX -11-AA NO. S1.
1. Outline KCl replenish-free type combination pH sensor KCl refillable type combination pH sensor, ORP sensor - AA *1 - AA PH72 - 11 PH72 - 13 - PH72 - 21 PH72 - 23 PH72 - 41 PH72 - 43 PH72 - 51 - Name plate *1 ( PH72SN-21-AA, PH72SN-23-AA, OR72SN-41-AA, OR72SN-43-AA ) Name plate *1 ( PH72SN-11-AA, PH72SN-13-AA ) Sensor cable Waterproof cover Prevents water ingress that may cause insulation failure. Sensor cable Waterproof cover Connector Connector Measures pH values.
1. Outline 1.7 Options (Available Separately) The following options are available for the Model PH72 Personal pH/ORP Meter for your convenience. When ordering, specify the part number. pH 9 Standard solution (Part no. : K9220XF) Soft carrying case (Part no. : B9269KJ) Sensor stand (Part no. : K9220XN) Approx. 280 Unit: mm 0 .3 rox Appr ox. 14 App Used for calibration when anticipated pH value of sample solution is alkaline.
1. Outline 1.8 Spare Parts pH 4 Standard solution (Part no. : K9084KF) Used for calibration. (250 ml) KCl solution (Part no. : K9220XH) pH 7 Standard solution (Part no. : K9084KG) Used for calibration. (250 ml) Quinhydrone reagent (Part no. : K9024EC) pH 9 Standard solution (Part no. : K9084KH) Used for calibration. (250 ml) Calibration bottle (Part no. : K9220WW) Used to replenish KCl refillable Used to check ORP electrode. 3 Used during calibration. 2 10-ml type sensor. 3.
1. Outline O-rings and gaskets are important parts to ensure that the PH72 meter is water resistant. Replace these parts as required. Refer to Section 6.7, “Storage and O-ring/Gasket Replacement” for replacement.
2. Preparation 2. Preparation 2.1 Installing the Batteries Install the batteries first. CAUTION Select a relatively moisture-free location when installing batteries in the meter. When installing batteries, observe correct polarity (battery orientation). Failure to do so may damage to the meter. Remove batteries from the meter if it is to be stored for an extended period of time. Do not leave dead batteries in the meter. They may leak and cause meter failure or erratic operation of the meter.
2. Preparation 2.2 Connecting the Sensor Cable Connect the sensor cable. CAUTION Connect the sensor cable in a place free from moisture. When connecting the sensor cable, tighten by turning only the silver locknut, do not turn the cable or waterproof cover. Also take care not wet or contaminate the connector. Sensors for the PH81 or PH82 meters can be connected. When used in conjunction with the PH72 meter, however, water resistance is not guaranteed.
2. Preparation 2.3 Setting the Date and Time After installing the batteries, set the date and time. Note that if the power is turned off before completing minute setting, start with the date setting when you turn on the power next time. By replacing the batteries, the date setting is not affected but the time setting is. So the time must be reset. Note: If a sensor cable is not connected to the meter, fluctuating readings or an error message may appear.
2. Preparation 2.4 Selecting pH or ORP Measurement Upon completing the date and time setting, the meter is ready for pH measurement. The display shows a pH value with a “pH” unit to the left of the value. To use the meter for ORP measurement, make sure that an ORP sensor is connected to the meter. Then, change the display for ORP measurement following the procedure described in Section 5.3 (3), “Set measurement unit (PV.U) panel.
2. Preparation 2.6 Manual Temperature Setting If a sensor without a built-in temperature element (needle type or test tube size pH mark will appear on the display. In this case, sensor) is connected to the meter, measure the temperature of the solution being measured and manually set the measured temperature into the PH72 meter for reliable measurement. The procedure is described in Section 5.3 (2), “Manual temperature setting (M.tP) panel.
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3. Measurement 3. Measurement 3.1 Precautions (1) After storage for an extended period of time, it is recommended that the meter should be calibrated before taking measurements. (2) When using a KCl refillable type sensor, check the level of filling solution. (Refer to Section 6.5.) (3) Do not use the meter in a solution with the temperature exceeding 808C (1008C for the needle type and test tube size pH sensors).
3. Measurement 3.2 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. This is to prevent the KCl filling solution from being mixed with the sample solution.
3. Measurement 3.3 Measurement Display Panel When immersing the sensor in a sample solution, a measured pH (or mV) value will be shown on the display. There are three types of measurement display panels: the standard, calendar, and clock display panels. Use Standard panel MEAS key to cycle through these display panels. Calendar panel Clock panel pH value (or mV) MEAS MEAS Solution temperature day month year hour:minute MEAS F030301.EPS 3.
3. Measurement (2) Data storage If the F/ENT DATA key is pressed during measurement, mark starts flashing. Press the key, then currently measured data can be stored in nonvolatile memory. Data stored are measured conductivity, measured temperature, date and time. Up to 300 data including individually deleted data can be stored. If you attempt to store more data, will be displayed. If is displayed before the data number has reached 300, run defrag referring to Section 5.
4. Calibration 4. 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 PH72 meter can be calibrated automatically or manually. The PH72 meter must be calibrated before measurement if: • it has been stored for a long period; • the electrode has been cleaned; or • otherwise necessary. Precautions (1) Use certified standard solutions.
4. Calibration Error Messages during Calibration If the meter detects an abnormality during calibration, , , or may be displayed. In such a case take corrective actions referring to Chapter 7, “Troubleshooting.” Canceling Calibration To cancel the calibration procedure, press CAL or MEAS key. The meter will return to measurement mode.
4. Calibration 4.1 Automatic Calibration In automatic calibration the Model PH72 Personal pH/ORP 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. standards). If NIST is selected, the meter recognizes standard solutions with pH 2, 4, 7, 9, and 12.
4. Calibration d Procedure Example 1: 2-point calibration using pH 7 and pH 4 standard solutions Water Wait until reading stabilizes. POWER Std. sol. Wash sensor with water thoroughly (or wash in water in beaker). Wipe off washing water from sensor thoroughly and then immerse sensor in standard solution.
4. 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 Thermometer Water Wait until reading stabilizes. POWER Std. sol. Wash sensor with water thoroughly (or wash in water in beaker). Wipe off washing water from sensor thoroughly and then immerse sensor in standard solution.
4. Calibration 4.2 Manual Calibration When using standard solutions other than those preprogrammed for automatic calibration (see Section 4.1), calibration should be performed manually. In 2-point calibration, manual calibration can be performed at both two points or manual calibration performed at one point (either 1st or 2nd) in combination with automatic calibration using a specified standard solution at the other point.
4. Calibration d Procedure Example 3: Manual calibration (2-point calibration) Water Wait until reading stabilizes. POWER Std. sol. Wash sensor with water thoroughly (or wash in water in beaker). Wipe off washing water from sensor thoroughly and then immerse sensor in standard solution. to select manual calibration (MAn) CAL F/ENT F/ENT Prompting Manual calibration is complete F/ENT to enter to confirm F0403.EPS For 2-pont calibration, continue the procedure following the dotted line.
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5. Keypad and Display Functions 5. Keypad and Display Functions There are eight membrane keys on the keypad of the Model PH72 Personal pH/ORP Meter. The following key functions are provided. • Displaying a pH (or mV) value and temperature • Displaying a pH (or mV) value, date and time • Holding a pH (or mV) value and temperature • Storing data — pH (or mV) value and associated information • Function mode • Calibration Turns power on or off. Automatic Power Off function (default: 20 min).
5. Keypad and Display Functions 5.1 Keypad Functions POWER : Power On/Off key Pressing and holding this key for at least one second when nothing is displayed on the LCD, will turn the meter on. The meter will be turned off by pressing and holding this key for at least two seconds when the meter is on. If no keys are pressed for a preset time, the meter turns off power automatically. (Refer to Section 5.3 (8), “Set Auto Power Off time (A.oFF) panel.
5. Keypad and Display Functions F/ENT : Entry key Pressing this key during measurement moves the display to function mode. (Refer to Section 5.3, “Function Modes.”) This key is also used to confirm data entry. Beep sound When a key is pressed, the meter acknowledges it using a beep sound. (1) One beep The meter will beep once confirming a valid key entry. (2) Three beeps The meter will beep three times if the key entry is invalid. To disable the beep, refer to Section 5.3 (9), “Set beep on/off (bZ.
5. Keypad and Display Functions 5.2 Display Items Display items and their descriptions are provided below. Battery condition indicator Temperature setting mode Manual mode Data mode HOLD mode Calibration mode Sensor check mode F050201.EPS (1) Battery condition indicator Indicates the level of the remaining battery life stepwise. means that there is plenty of life left. A flashing means that the batteries are low and need to be replaced immediately.
5. Keypad and Display Functions 5.3 Function Mode Outline Various functions are supported by function mode. Press F/ENT key while the meter 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. Setting Procedures Use keys to move to the desired item. While the desired item is flashing, press F/ENT key to access that item panel.
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 (mV) value and temperature will be displayed with the data number flashing at the lower left of the display. Pressing keys scrolls through all stored data. If no data are stored, “no dAtA” is displayed at the bottom of the display.
5. Keypad and Display Functions F/ENT to display other data Day and month data item was stored Stored measurement data DATA Year data item was stored DATA Latest data DATA "Delete stored data" panel DATA Time data item was stored F/ENT DATA F/ENT Delete stored data F/ENT When no stored data. F/ENT F050301.
5. Keypad and Display Functions (2) Manual temperature setting (M.tP) panel Used to input the temperature of a solution into the meter when using a sensor without a built-in temperature element (needle type or test tube size pH sensor). This setting is not required when a sensor connected has a built-in temperature element. The setting range is from -10.0 to 110.08C. to set F/ENT to confirm F/ENT F050302.EPS (3) Set measurement unit (PV.
5. Keypad and Display Functions (5) Date setting (dAtE) panel Used to set the year (four digits), month and day in this order. Use year, month, and day, and press F/ENT keys to set the key to confirm each entry. Year setting Month setting F/ENT F/ENT F/ENT Day setting F/ENT F050305.EPS The calendar function will be valid through to year 2090. (6) Time setting (tIME) panel Used to set the time — hour (24-hour format) and minute in this order.
5. Keypad and Display Functions (7) Alarm time setting (ALM) panel Used to enable/disable the alarm clock and set the alarm clock in minutes and seconds. Use keys to select the desired alarm cycle: 7 days (everyday), 5 days (weekdays) or once. See Item (6), “Time setting (tIME) panel” for setting the time for alarm. The alarm sounds for about 15 seconds. Acknowledge the alarm by pressing any key. The alarm sound will stop.
5. Keypad and Display Functions (8) Set Auto Power Off time (A.oFF) panel Used to set the automatic power off time. The meter turns off power automatically if no key is pressed during this preset time. The time range is from 1 to 120 minutes. If 0 is set, the Auto Power Off function will be disabled. Use the meter taking care to conserve the batteries. to set F/ENT to confirm F/ENT F050308.EPS (9) Set beep on/off (bZ.o) panel The beep sound on key press can be enabled/disabled in this panel.
5. Keypad and Display Functions (11) Initialize calibration parameters (I.CP) panel Used to initialize the parameters saved by calibration to default settings: slope at 1.000 and asymmetry potential at 0.0 mV. F/ENT to toggle to proceed F/ENT to cancel F/ENT to execute F050311.EPS (12) Set temperature unit (tP.U) panel Used to select the temperature unit: Celsius (8C) or Fahrenheit (8F). Use select the desired temperature unit and press F/ENT F/ENT keys to key to confirm.
5. Keypad and Display Functions (14) Defrag memory (dFLG) panel Up to 300 data can be stored. Unnecessary data can be individually deleted (refer to Item (1), “Display stored data”), but this individual deletion does not free up memory occupied by deleted data. Therefore, may be displayed even though less than 300 data are stored. In such a case, use the defrag function to consolidate data and free up the space occupied by deleted data, thereby allowing up to 300 data to be stored.
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6. Maintenance 6. Maintenance 6.1 For Optimum Meter Performance The Model PH72 Personal pH/ORP 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 Maintenance Storage F060101.EPS Table 6.1 Precautions in Each Step Calibration using standard solutions: • 1- or 2-point calibration. 2-point calibration is recommended for accurate pH measurement.
6. Maintenance 6.2 pH Electrode Cleaning Dirt or deposits on the glass electrode or liquid junction can often interfere with accurate measurement. Periodical cleaning is required depending on the nature of the solution being measured. 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.
6. Maintenance After 10 to 20 minutes 0.1 mol/l dilute hydrochloric acid Cleaning water Soak in 0.1 mol/l hydrochloric acid Figure 6.2 Rinse thoroughly in water F0602.EPS Acid Cleaning 6.3 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.
6. Maintenance 6.5 Replenishing the Electrode with Filling Solution (KCl solution) Replenishment is required only when a KCl refillable type combination sensor is used. An electrode filling solution leaks from the liquid junction little by little during measurement. When the level of filling solution drops to the level shown in Figure 6.3, replenish with a 3.3 mol/l KCl solution supplied. CAUTION A syringe tip is sharp. Handle with care.
6. Maintenance 6.6 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. O-ring Wipe off stains and/or moisture on meter connector with a dry cloth. Check that there are no stains on the O-ring.
6. Maintenance 6.7 Storage and O-ring/Gasket Replacement • Storage Precautions Care is required when storing the meter and sensor. To maintain in good condition, observe the following: (1) Before storage, wash off remaining sample solution from the sensor with water. Deposits on the liquid junction, if any, must be removed thoroughly, or the junction may be clogged. A clogged junction will cause invalid measurements, e.g., unstable pH readings. Keep a wetting cap attached to the sensor.
6. Maintenance (1) Replacing the O-ring Install the O-ring on the cylindrical flat part of the connector, as shown below. O-ring F060701.EPS (2) Replacing the Gasket 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 PH72 meter top Raised part F060702.
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7. Troubleshooting 7. Troubleshooting 7.1 Causes of Abnormal Readings and Errors If the pH reading is unstable or abnormal, or an error message appears, during measurement or calibration, check the following: (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.
7. Troubleshooting 7.2 Error Messages, Possible Causes, and Corrective Actions Table 7.1 Error Message Error Message*1 Description Err1 Unstable input emf Err2 Abnormal asymmetry potential Err3 Abnormal slope or calibration temperature Err4 Out of measuring range Err5 Out of temperature measuring range Err6 Meter electronics failure Occurrence During calibration During measurement *1: For displayed digital characters, see Alphanumeric Display Table in Preface. T0701.
7. Troubleshooting (2) Err2 Abnormal asymmetry potential Appears during calibration. A sensor deteriorates in service and the emf deviates from the initial one. If the difference increases and exceeds the limit that can be compensated by calibration, an Err2 message will appear. It will also appear if the pH value of the standard solution is abnormal or if the asymmetry potential is outside the range of -96 to 120 mV. Possible Causes: • Clogged liquid junction. • Insulation failure in electronics.
7. Troubleshooting (3) Err3 Abnormal slope or calibration temperature Appears during calibration. In the Model PH72 Personal pH/ORP 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. It will also appear if the slope is outside the range of 65 to 125%. Possible Causes: • Defective standard solutions.
7. Troubleshooting (5) Err5 Out of temperature measuring range Appears during measurement. With the Model PH72 Personal pH/ORP Meter, a general-purpose sensor can be used in the temperature range of 0 to 808C and a needle type or test tube size sensor in the temperature range of 0 to 1008C. If the operating temperature is significantly outside this measuring range (below -10.08C or above 1208C), an Err5 message will appear.
7. Troubleshooting 7.4 Other Conditions • An alarm sounds The alarm is set to sound at the preset alarm time. Refer to Section 5.3 (7), “Alarm time setting (ALM) panel.” • Beeps The beep sound to acknowledge a key press can be enabled/disabled. Refer to Section 5.3 (9), “Set beep on/off (bZ.o) panel.” • appears This indicates that the electrode has deteriorated. The electrode may be used continuously even after this mark appears.
8. ORP Meter 8. ORP Meter 8.1 ORP Measurement Use a dedicated ORP sensor for ORP (oxidation-reduction potential) measurement. The ORP sensor is a KCl refillable type with a platinum sensing electrode and looks the same as a KCl refillable type pH sensor. The measuring temperature range of the ORP sensor is 0 to 808C, the same as that of the pH sensor. • The default setting for measurement unit of the Model PH72 Personal pH/ORP Meter is pH. Press F/ENT key and follow the procedure described in Section 5.
8. ORP Meter 8.2 Maintenance of ORP Sensors Maintenance of ORP sensors is in accordance with that of pH sensors. (Refer to Chapter 6, “Maintenance.”) Cleaning the Platinum Electrode and Liquid Junction Dirt or deposits on the platinum electrode or liquid junction may interfere with accurate measurement. Periodical cleaning is required depending on the nature of the solution being measured. As in the same manner for pH sensors, use a cotton swab or brush to clean. (See Section 6.2.
8. ORP Meter 8.3 Checking the ORP Sensor Use a check solution to verify that the ORP sensor operates properly. The oxidationreduction potential of the check solution to be used should have been correctly determined by a normal ORP sensor. The following explains how to check an ORP sensor using a quinhydrone reagent (spare part). Preparing a Quinhydrone Solution Prepare a 250 ml solution in a wide mouthed bottle by dissolving one pack of quinhydrone reagent in deionized water.
8. ORP Meter 400 Oxidation-reduction potential (mV) Quinhydrone solution 300 200 100 Tolerance 0 0 Figure 8.2 8-4 10 20 30 Temperature (8C) 40 50 F0802.
9. Technical Information 9. Technical Information 9.1 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 9.1 shows the schematic diagram of the measurement principle.
9. Technical Information 9.2 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. Therefore, a pH meter must be calibrated using standard solutions.
9. Technical Information Boundary layers H + H+ Internal solution side Sample solution side eS ei Hydrated layers on glass Figure 9.2 F0902.EPS Diagram of Glass Membrane 500 400 300 200 E (mV) 100 0 -100 -200 -300 Alkaline error -400 -500 0 2 4 8 6 pH Figure 9.3 IM 12B03D02-01E 10 12 14 F0903.
9. Technical Information 9.3 Temperature Compensation In equation 9.3, 2.3026RT/F represents the emf per pH unit and varies depending on temperature. Table 9.1 Temperature (8C) 0 5 10 15 20 25 30 EMF per pH (values of 2.3026RT/F) 2.3026RT/F (mV) 54.20 55.19 56.18 57.18 58.17 59.16 60.15 Temperature (8C) 35 40 45 50 55 60 65 2.3026RT/F (mV) 61.14 62.14 63.13 64.12 65.11 66.11 67.10 Temperature (8C) 70 75 80 85 90 95 100 2.3026RT/F (mV) 68.09 69.08 70.07 71.07 72.06 73.05 74.04 T0901.EPS Table 9.
9. Technical Information Table 9.2 Temp.(8C) pH 1 3 5 7 9 11 13 Deviations from True Values in Measurement without Temperature Compensation 0 20 25 40 60 80 0.50 0.34 0.17 0.00 -0.17 -0.34 -0.50 0.10 0.07 0.03 0.00 -0.03 -0.07 -0.10 0.00 0.00 0.00 0.00 0.00 0.00 0.00 -0.30 -0.20 -0.10 0.00 0.10 0.20 0.30 -0.70 -0.47 -0.23 0.00 0.23 0.47 0.70 -1.11 -0.74 -0.37 0.00 0.37 0.74 1.11 T0902.EPS In addition, the pH value of a solution changes with temperature.
9. Technical Information 9.5 The Alkaline Error As shown in Figure 9.5, the emf of a glass electrode deviates from the linear value on the alkaline side. This is called the alkaline error. The magnitude of the alkaline error varies depending on the glass membrane compositions. The alkaline error is likely to occur with the presence of sodium and lithium and even with the same pH, it varies depending on the types and concentrations of cations and on the temperature.
Alkaline error (mV) 9. Technical Information 60 Solution temperature at 258C 40 3mol/l-Na + 1mol/l-Na+ 20 0.1mol/l-Na+ 0 9 11 10 12 Test solution pH Figure 9.7 13 14 F0907.EPS Ion Concentration vs Alkaline Error 9.6 The Acid Error Acid error (mV) The acid error also varies depending on the glass membrane compositions and the types of acids. It increases gradually with immersion time and finally reaches equilibrium.
9. Technical Information 9.7 Calibration Calculation The PH72 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 9.9). The second calibration is done so a line is drawn through the first and second calibration points (Figure 9.10). One-point calibration is a simplified method where only the first calibration of 2-point calibration is performed.
9. Technical Information 9.8 ORP (Oxidation-Reduction Potential) In general, oxidation is the gain of oxygen or the loss of hydrogen, and reduction is the loss of oxygen or the gain of hydrogen. In the electrochemistry field, oxidation is defined as the loss of electrons and reduction is defined as the gain of electrons.
9. Technical Information 9.9 Reference Electrode The oxidation-reduction potential in measurement is a value relative to the reference electrode. If different types of reference electrodes are used, the oxidation-reduction potentials of identical solutions are apparently different. In the electrochemical field, the hydrogen electrode is generally used as a reference electrode. However, it has complicated construction and is impractical.
9. Technical Information Obtained from equation 9.10, the potential of the Ag/AgCl electrode filled with a 3.3 mol/l KCl solution, E'AgCl, has the temperature characteristic for the standard hydrogen electrode as shown in Figure 9.12. To convert E'AgCl to the value for the standard hydrogen electrode, ' E SHE 5 E 1 EAgCl 1 Ej (9.11) [mV] 3.
9. Technical Information 9.
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. d When turn on power Toggle display type POWER or First time used, or after replace batteries or MEAS F/ENT MEAS F/ENT MEAS F/ENT or d Temporary hold HOLD HOLD MEAS F/ENT F/ENT d Storing data DATA F/ENT DATA MEAS T01.
Appendix d Function Mode Manual temperature setting Display stored data Set measurement unit F/ENT F/ENT F/ENT F/ENT or F/ENT DATA F/ENT DATA DATA DATA F/ENT F/ENT T02.
Appendix d Function Mode Date setting Delete all stored data F/ENT F/ENT Time setting 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 d Switching to Function Mode Measurement status d Reverting to Measurement Mode F/ENT Measurement status MEAS T03.
Appendix d Function Mode Set beep on/off F/ENT F/ENT Standard solution setting F/ENT F/ENT Initialize calibration parameters Set temperature unit F/ENT F/ENT F/ENT F/ENT d Function Mode Check version number F/ENT Defrag memory F/ENT F/ENT T04.
Appendix d Calibration Automatic calibration & Manual calibration (2-point calibration) Measurement status Auto calibration in progress Auto calibration Auto calibration is complete F/ENT CAL 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 status Auto calibration CAL Temperature set on 'M.tP' panel F/ENT 25.
Appendix 6 IM 12B03D02-01E
MSDS MSDS (Material Safety Data Sheet) The contents are provided for informative purposes only and no guarantee is given to the accuracy. The information, such as manufacturers, in the data sheets is subject to change without notice.
MSDS MSDS-2 IM 12B03D02-01E
MSDS IM 12B03D02-01E MSDS-3
MSDS MSDS-4 IM 12B03D02-01E
MSDS IM 12B03D02-01E MSDS-5
MSDS MSDS-6 IM 12B03D02-01E
MSDS IM 12B03D02-01E MSDS-7
MSDS MSDS-8 IM 12B03D02-01E
MSDS IM 12B03D02-01E MSDS-9
MSDS MSDS-10 IM 12B03D02-01E
MSDS IM 12B03D02-01E MSDS-11
MSDS MSDS-12 IM 12B03D02-01E
MSDS IM 12B03D02-01E MSDS-13
MSDS MSDS-14 IM 12B03D02-01E
MSDS IM 12B03D02-01E MSDS-15
MSDS MSDS-16 IM 12B03D02-01E
MSDS IM 12B03D02-01E MSDS-17
MSDS MSDS-18 IM 12B03D02-01E
MSDS IM 12B03D02-01E MSDS-19
MSDS MSDS-20 IM 12B03D02-01E
MSDS IM 12B03D02-01E MSDS-21
MSDS MSDS-22 IM 12B03D02-01E
Revision Record Manual Title : Model PH72 Personal pH/ORP Meter Manual Number : IM 12B03D02-01E Edition 1st 2nd Date Oct. 2004 Apr. 2008 3rd Apr. 2009 Remark (s) Newly published Addition of information on EMC compliance: P.1-2 Addition of CAUTION: P2-2 Correction: P.1, 1-2, 1-6, 2-1, 2-5, 3-1, 5-4, 6-1, 7-6, 8-3, 9-4, 9-6, 9-7 Change of information on EMC compliance: P.
