JP4614841B2 - Redox potential measuring device - Google Patents

Description

  The present invention relates to an oxidation-reduction potential measuring device that measures the oxidation-reduction potential of a test solution. More specifically, the present invention easily determines the oxidation-reduction potential Eh value of a test solution according to the temperature of the test solution. The present invention relates to an oxidation-reduction potential measuring apparatus capable of performing the same.

The oxidation-reduction potential measuring device is used to measure the degree of force with which one substance oxidizes or reduces another substance. When a hydrogen electrode and a platinum electrode are inserted into an aqueous solution in a redox reversible equilibrium state, one reversible battery is formed, and a constant potential difference is detected according to the redox equilibrium state of the solution. This potential difference is called “Oxidation-Reduction Potential” and is expressed as “ORP” in English. The oxidation-reduction potential can be expressed by the following equation (Nernst equation).
Eh = E ₀ + (RT / nF) × ln ([Ox] / [Red])
(However, [Ox]: Activity of oxide, [Red]: Activity of reduced product, E ₀ : Redox potential (standard potential difference) when [Ox] = [Red], F: Faraday constant, n : Number of electrons transferred per molecule, R: gas constant, T: temperature of aqueous solution (absolute temperature))

E _{0 in the} above formula is a redox potential when [Ox] = [Red], and has a unique value in each redox system. By the way, NHE (Normal Hydrogen Electrode), which is a standard hydrogen electrode, immerses a platinum electrode with platinum black in a solution in which the activity of hydrogen ions is 1, for example, 1.18 mol hydrochloric acid solution, and hydrogen at 1 atm. Obtained through gas. The standard hydrogen electrode potential is promised to be 0 mV at all temperatures and is accepted as an international reference electrode. The oxidation-reduction potential Eh is expressed as a potential based on the NHE. However, since the hydrogen electrode has a complicated configuration and is not practical, the redox potential is usually measured by placing a redox potential measuring electrode (measuring electrode) such as a platinum electrode and a reference electrode in the test solution. This is done by reading the indicated value. Since the reference electrode used in this case is different from the standard hydrogen electrode, a silver / silver chloride electrode or a calomel electrode is used. Therefore, the obtained indicated value is not a correct redox potential Eh value. . In order to obtain the oxidation-reduction potential Eh value, it is necessary to add the value of the potential difference between the standard hydrogen electrode and the reference electrode (hereinafter referred to as “unipolar potential” of the comparison electrode) to the measured value.

  Therefore, conventionally, the measurer calculates from the measured value of the potential difference between the measurement electrode and the reference electrode using a table indicating the relationship between the temperature and the unipolar potential of the reference electrode, The oxidation-reduction potential Eh value is obtained.

  Alternatively, in a device having a function of shifting the indicated value, the temperature of the test solution is measured, and the monopolar potential of the reference electrode at that temperature is obtained using the above table, and the measured value is equal to the monopolar potential. By shifting and instructing, the oxidation-reduction potential Eh value of the test solution can be instructed. However, in this method, if the temperature changes, it is necessary to reset the value for shifting the measured value.

  Thus, conventionally, in order to measure the oxidation-reduction potential Eh value of the test solution, it is necessary to perform a manual calculation by the measurer or to set a shift value every time the temperature changes. There is also sex.

Here, Patent Document 1 discloses an oxidation-reduction electrode pass / fail determination device that uses a memory for determining pass / fail of an oxidation-reduction potential measurement electrode. That is, in the invention of Patent Document 1, a memory is prepared that stores in advance a change characteristic data table of a redox potential with respect to a temperature change of a check solution that clearly shows a change characteristic of the redox potential with respect to a temperature change. When determining the quality of the redox potential measuring electrode, the information in the memory is used to calculate the allowable range of the potential according to the temperature of the check solution in which the redox potential measuring electrode is immersed. It is determined whether it is within the allowable range. In Patent Document 1, there is no mention of indicating the oxidation-reduction potential Eh value, and there is no mention of the above-described problem in the case of indicating the oxidation-reduction potential Eh value.
Japanese Patent Laid-Open No. 3-261854

  An object of the present invention is to provide an oxidation-reduction potential measuring device capable of easily obtaining the oxidation-reduction potential Eh value of a test solution.

  The above object is achieved by the oxidation-reduction potential measuring apparatus according to the present invention. In summary, according to the present invention, in a redox potential measuring device having a redox potential measuring electrode, a comparative electrode, and a temperature detecting means, table data indicating a relationship between a unipolar potential of the comparative electrode and a temperature is obtained. Unipolar potential information storage means for storing; a unipolar potential of the comparison electrode corresponding to an output signal from the temperature detection means is obtained based on the table data; and output from the oxidation-reduction potential measurement electrode and the comparison electrode Signal processing means for obtaining a potential difference between both electrodes based on the signal and calculating a redox potential Eh value from the potential difference and the unipolar potential; and information indicating the redox potential Eh value calculated by the signal processing means; An oxidation-reduction potential measuring device characterized by comprising:

  According to one embodiment of the present invention, the oxidation-reduction potential measuring device further includes means for outputting information indicating the potential difference.

  According to an embodiment of the present invention, the oxidation-reduction potential measuring device further outputs a means for adding and subtracting a predetermined value to the potential difference and shifting, and information indicating a value obtained by shifting the potential difference by the predetermined value. Means.

  According to an embodiment of the present invention, the unipolar potential information storage means stores a plurality of the table data corresponding to a plurality of different types of comparison electrodes. The oxidation-reduction potential measuring device may further include a transmission unit that transmits information indicating the type of the comparison electrode to the signal processing unit. The transmission means is accompanied by input means for inputting information indicating the type of the comparison electrode by an operator's operation, or information indicating the type of the comparison electrode that can be attached to and detached from the signal processing means together with the comparison electrode. It may be an identification means. In a preferred embodiment, the identification means is a storage medium that can be attached to and detached from the signal processing means together with the comparison electrode. Here, the plurality of reference electrodes of different types may have different internal electrodes and / or electrode internal liquids.

  That is, in order to calculate the oxidation-reduction potential Eh value from the measured value of the potential difference between the measurement electrode and the comparison electrode, it is necessary to add the unipolar potential of the comparison electrode to the measurement value. Derived from the relationship with temperature. Therefore, a table showing the relationship between the unipolar potential of the reference electrode and the temperature is prepared, and the unipolar potential of the reference electrode at that temperature is obtained from the temperature of the test solution at the time of measurement. Is added to the measured value so that it can be directly displayed as the oxidation-reduction potential Eh value of the test solution. In addition to the mode for displaying the oxidation-reduction potential Eh value, at least one of the mode for displaying the value of the potential difference between the measurement electrode and the comparison electrode as it is and the mode for displaying the value obtained by shifting the potential difference is displayed. And can be selected as desired. The measurer can use these modes according to the purpose.

  According to the present invention, the oxidation-reduction potential Eh value can be directly displayed without manual calculation by the measurer or setting of a shift value. Therefore, according to the present invention, the oxidation-reduction potential Eh value of the test solution can be easily obtained.

  Hereinafter, the oxidation-reduction potential measuring apparatus according to the present invention will be described in more detail with reference to the drawings.

Example 1
FIG. 1 is a schematic block diagram showing an embodiment of the oxidation-reduction potential measuring apparatus according to the present invention. In this embodiment, the oxidation-reduction potential measuring device 100 is integrally formed with an oxidation-reduction potential measurement electrode (measurement electrode) 1, a comparison electrode 2, and a temperature sensor 3 as temperature detection means for detecting the temperature of the test liquid. The composite electrode for redox measurement (hereinafter referred to as “ORP composite electrode”) A and the main body B are connected and used. In this embodiment, the measurement electrode 1 is a platinum electrode. In this embodiment, the reference electrode 2 is a 3.3 mol / L silver chloride electrode that uses a silver chloride electrode as an internal electrode and 3.3 mol / l potassium chloride (KCl) as an internal solution. . The temperature sensor 3 includes a resistance temperature detector.

  The main body B generally includes a main body side connector 5 for connecting the ORP composite electrode A, an amplification circuit 6 for amplifying an output signal from the ORP composite electrode A, and A / D conversion, a temperature detection circuit 7, and a switching device. 8 and A / D converter 9, a CPU circuit 10 as a signal processing means for processing an output signal from the ORP composite electrode A, a display 14 for displaying a measurement result, a measurement start or end instruction and various settings. An operation unit 15 for inputting to the CPU circuit 10, a power supply jack 16 to which the cord L2 of the AC adapter 4 is connected, a power supply circuit 17 for supplying operating power of the apparatus, and the like.

The measurement electrode 1, the comparison electrode 2, and the temperature sensor 3 included in the ORP composite electrode A are connected to the main body side connector 5 of the main body B via the lead L1 and an electrode side connector (not shown). When performing the measurement, the ORP composite electrode A (that is, the measurement electrode 1, the comparison electrode 2, and the temperature sensor 3) is immersed in the test solution S accommodated in the container. Output signals from the measurement electrode 1 and the comparison electrode 2 are appropriately amplified by the amplifier circuit 6. The output signal from the temperature sensor 3 is appropriately amplified by the temperature detection circuit 7. The analog signals amplified by the amplifier circuit 6 and the temperature detection circuit 7 are selectively input to the A / D converter 9 via the switcher 8, converted into digital signals, and then input to the CPU circuit 10, respectively. The The calculation unit 11 of the CPU circuit 10 receives measurement data (potential difference data) corresponding to the potential difference between the measurement electrode 1 and the comparison electrode 2 and measurement data corresponding to the temperature of the test solution S (from the input signal). (Calculation processing necessary to obtain temperature data). The obtained potential difference data and temperature data are temporarily stored in the measurement data storage unit 13 provided in the CPU circuit 10. The measurement data storage unit 13 is composed of a RAM.

  On the other hand, the table data storage unit 12 serving as unipolar potential information storage means for storing information related to the temperature dependence of the unipolar potential of the comparison electrode provided in the CPU circuit 10 has 3.3 mol / th as the comparison electrode 2. Table data (temperature-potential table) as shown in the following Table 1 showing the relationship between the monopolar potential of the L silver chloride electrode and the temperature is stored in advance. The table data storage unit 12 is composed of a ROM. Incidentally, the unipolar potential of the 3.3 mol / L silver chloride electrode coincides with the value of the potential difference between it and the standard hydrogen electrode.

  Then, the CPU circuit 10 reads the potential difference data temporarily stored in the measurement data storage unit 13 and the temperature data when the potential difference data is obtained into the calculation unit 11 and corresponds to the temperature data. The monopolar potential data of the comparison electrode 2 to be selected is selected from the table data storage unit 12 and read into the calculation unit 11. And in the calculating part 11, the calculation process which adds monopolar potential data to potential difference data is performed, and the oxidation reduction potential Eh value is calculated. The CPU circuit 10 outputs information indicating the calculated oxidation-reduction potential Eh value to the display 14 and causes the display 14 to display the oxidation-reduction potential Eh value. In the present embodiment, the display device 14 functions as means for outputting information indicating the calculated oxidation-reduction potential Eh value.

  In this embodiment, as a display method of the measurement value, in addition to the above-described mode for displaying the oxidation-reduction potential Eh value, a voltage value (mV) corresponding to the potential difference between the measurement electrode 1 and the comparison electrode 2 is used. It is possible to select a mode for displaying as it is, and a mode for displaying a value (mV) obtained by shifting a voltage value corresponding to the potential difference between the measurement electrode 1 and the comparison electrode 2 by a desired amount. The operation unit 15 is provided with a mode selection key for designating a display method of the measurement result. When the measurer inputs from the operation unit 15, information for selecting the display method of the measurement value is transmitted from the operation unit 15 to the CPU. Input to the circuit 10. Further, the operation unit 15 is provided with a shift value input key for inputting a value for shifting the measured value of the potential difference between the measuring electrode 1 and the comparison electrode 2, and the measured value of the potential difference is shifted and displayed. When selecting a mode, the measurer also inputs a shift value in the operation unit 15. As a result, information indicating the shift value is input from the operation unit 15 to the CPU circuit 10. The CPU 10 causes the display 14 to display the measurement result by any one of the above-described display methods according to the information specifying the display method of the measurement values input from the operation unit 15. In other words, in the present embodiment, the display unit 14 outputs information indicating a potential difference between the measurement electrode 1 and the comparison electrode 2, or outputs information indicating a value obtained by shifting the potential difference by the predetermined value. It also functions as a means. The CPU circuit 10 also has a function as means for shifting by adding or subtracting a predetermined value to the potential difference between the measurement electrode 1 and the comparison electrode 2. Note that necessary information such as the temperature information of the test solution S and the monopolar potential of the comparison electrode 2 may be displayed at the same time.

  FIG. 2 is a flowchart showing an outline of the processing procedure of the CPU circuit 10 in the above-described oxidation-reduction potential measuring apparatus 100. When the oxidation-reduction potential measuring apparatus 100 is turned on (S101), the apparatus is initialized (S102). Next, the potential difference between the measurement electrode 1 and the comparison electrode 2 and the temperature of the test solution S are measured, and the measurement data is stored in the measurement data storage unit 13 (S103, S104). Next, information for designating the display method of the measured value input from the operation unit 15 to the CPU circuit 10 is confirmed (S105).

  In S105, when it is determined that the mode for displaying the oxidation-reduction potential Eh value is selected as the measurement value display method, the potential difference data and the temperature data are read from the measurement data storage unit 13 into the calculation unit 11 and the table data is displayed. The unipolar potential data corresponding to the temperature data is selected from the storage unit 12 and read into the calculation unit 11, and the calculation unit 11 adds the unipolar potential data to the potential difference data to calculate the oxidation-reduction potential Eh value (S106). . Next, information indicating the calculated oxidation-reduction potential Eh value and further information indicating the temperature of the test solution are output to the display unit 14, and the display unit 14 displays the oxidation-reduction potential Eh value and further the temperature. (S107).

  In S105, if it is determined that the mode for displaying the potential difference between the measurement electrode 1 and the comparison electrode 2 as it is is selected as the display method of the measurement value, the potential difference data and the temperature data are stored from the measurement data storage unit 13. , Information indicating the potential difference, and further information indicating the temperature is output to the display 14, and the display 14 displays the potential difference (mV) and the temperature (S107).

  Further, in S105, when it is determined that the mode for displaying the potential difference by shifting the potential difference by a desired amount is selected as the display method of the measured value, the potential difference data and the temperature data are read from the measurement data storage unit 13 into the calculation unit 11. Separately, the shift value data inputted and stored in the CPU circuit 10 from the operation unit 15 is read into the calculation unit 11, and the shift value data is added to or subtracted from the potential difference data. Then, the information indicating the value obtained by shifting the potential difference between the measuring electrode 1 and the comparison electrode 2 by a desired amount, and further the information indicating the temperature are output to the display device 14, and the shifted value is displayed on the display device 14. (MV) and further the temperature is displayed (S107).

  Thus, according to the present embodiment, the oxidation-reduction potential Eh value can be directly displayed without manual calculation by the measurer and setting of the shift value. Therefore, according to the present embodiment, the oxidation-reduction potential Eh value of the test solution can be easily output. Further, in addition to the oxidation-reduction potential Eh value, the potential difference between the measurement electrode and the comparison electrode can be displayed as it is or shifted by a desired amount as in the prior art. These display methods can be used properly.

Example 2
Next, another embodiment of the present invention will be described. The basic configuration of the oxidation-reduction potential measuring apparatus of the present embodiment is the same as that of the first embodiment. Therefore, elements having the same or corresponding functions and configurations as those of the first embodiment are denoted by the same reference numerals and detailed description thereof is omitted, and characteristic points of the present embodiment will be described below.

  3 and 4 are schematic block diagrams of the oxidation-reduction potential measuring apparatus 100 of the present embodiment. In this embodiment, the oxidation-reduction potential measuring apparatus 100 can use a plurality of types of comparison electrodes 2. In this embodiment, as the comparison electrode 2, a saturated sweet potato electrode (internal electrode is mercuric chloride, internal liquid is saturated potassium chloride), saturated silver chloride electrode (internal electrode is silver chloride, internal liquid is saturated potassium chloride), 3 A 0.3 mol / L silver chloride electrode (internal electrode is silver chloride, and internal solution is 3.3 mol / L potassium chloride) can be used. In particular, in this embodiment, the ORP composite electrodes A1, A2 and A3 each having the above three types of comparison electrodes 2 can be exchanged and connected to the main body B for use.

  Here, the theoretical value of the temperature dependence of the monopolar potential of the reference electrode is typically determined by the internal liquid of the reference electrode. Therefore, in this embodiment, the table data storage unit 12 of the CPU circuit 10 stores table data (temperatures) as shown in Table 2 below showing the relationship between the unipolar potential and the temperature corresponding to each of the three types of comparison electrodes. -Potential table) is stored in advance. Then, it is possible to set which type of comparison electrode 2 is used or which type of comparison electrode 2 is connected to the main body B. Note that the unipolar potentials of these three types of comparison electrodes coincide with the value of the potential difference between this and the standard hydrogen electrode.

  In Table 2, for convenience, the temperature column is shown in common for each type of reference electrode 2, but the storage form of the table data is not limited to this. In the present invention, storing a plurality of table data corresponding to a plurality of reference electrodes of different types means that the unipolar potential data can be selected from the temperature data corresponding to the type of the comparison electrode. It includes memorizing the relationship between monopolar potential and temperature. In other words, in this embodiment, the table data storage unit 12 includes a plurality of storage areas for storing table data indicating the relationship between the unipolar potential of the comparison electrode and the temperature corresponding to each of the different types of comparison electrodes. Have.

  For example, as shown in FIG. 3, as means for transmitting information indicating the type of the comparison electrode 2 to be used to the CPU circuit 10, an operation that is input means for inputting information indicating the type of the comparison electrode 2 by the operation of the operator. Part 15 can be used. In this case, the operation unit 15 is provided with an electrode type selection key for designating the comparison electrode 2 to be used (that is, the ORP composite electrodes A1, A2, and A3 to be used in this embodiment). By inputting, information indicating the type of the comparison electrode 2 to be used (that is, the ORP composite electrodes A1, A2, and A3 to be used in this embodiment) is input from the operation unit 15 to the CPU circuit 10.

  Further, when the ORP composite electrode A (that is, the comparison electrode 2) is exchanged and connected to the main body B as in this embodiment, information indicating the type of the comparison electrode 2 is provided. As a means for transmitting to the CPU circuit 10, the comparison electrode 2 (that is, ORP composite electrodes A 1, A 2, and A 3 in this embodiment) is detachably attached to the main body B (that is, the CPU circuit 10) together with the comparison electrode 2. Means can be provided. The identification means may be of any shape that can be recognized on the main body B side.

  For example, as shown in FIG. 4, an EEPROM (Electrically Erasable Programmable Read-Only Memory) provided in the ORP composite electrodes A1, A2, and A3 is used as an identification means for transmitting the type of the comparison electrode 2 to the CPU circuit 10. An identification information storage means 20 that is a storage medium that can be attached to and detached from the main body B (that is, the CPU circuit 10) can be used together with the comparison electrode 2, such as an erasable / writeable read-only memory. That is, the identification information storage means 20 stores information (identification information) indicating the types of comparison electrodes mounted on the ORP composite electrodes A1, A2, and A3. The identification information storage means 20 can be provided, for example, in an electrode side connector (not shown) for connecting the lead L1 of the ORP composite electrode A to the connector 5 on the main body B side. Thereby, in a state where the ORP composite electrodes A1, A2, A3 are connected to the main body B, the CPU circuit 10 can read the contents of the identification information storage means 20 at a predetermined timing and recognize the type of the comparison electrode 2. Thus, in the case of a comparison electrode with a storage medium, it is possible to automatically acquire information indicating the type, such as what is used as the internal liquid, from the ID information on the main body B side. .

  The identification means for inputting the type of the comparison electrode 2 to the CPU circuit 10 is not limited to the identification information storage means 20 that is the EEPROM. For example, as a form of the storage medium as the identification means, in addition to the EEPROM, a flash memory, a battery backup RAM, an EPROM, a one-time ROM, a CPU with a memory, and the like can be given. Further, as identification means, physical quantity or state changing means such as switches, analog switches, resistors, capacitors, etc .; physical quantity generating means such as voltage generators, current generators, light generators; physical shape changes; or bar codes, etc. Can also be used. Similar to the above, these identification means can also be provided on, for example, an electrode-side connector (not shown) for connecting the lead L1 of the ORP composite electrode A to the connector 5 on the main body B side. These identification means are preliminarily attached with information capable of identifying at least the type of the comparison electrode.

  On the other hand, on the main body B side, a recognition means for recognizing information attached to the identification means is provided. If the identification means is a storage medium, means for reading and recognizing the stored contents (in the embodiment shown in FIG. 4, the CPU circuit 10 has the function in this embodiment). In addition, corresponding to the above various identification means, a recognition means capable of recognizing this can be provided on the main body B side. For example, when the identification means is a physical quantity or state change means, the recognition means is a means for recognizing a change in the physical quantity or state. If the identification means is a physical quantity generation means, the recognition means accepts the physical quantity and identifies it. If the identification means is a physical shape change, the identification means is a means for identifying the physical shape change. If the identification means is a barcode, the recognition means is for identifying the barcode. It can be used as a means. However, the identification means is preferably a storage medium that is an electronic memory in terms of cost, ease of information transmission, and the amount of information that can be attached. This storage medium may be a non-contact type capable of wirelessly communicating with the recognition means on the apparatus main body side.

  In this embodiment, the calculation unit 11 of the CPU circuit 10 uses the connected reference electrode 2 indicating the type of the comparison electrode 2 to be used or connected (that is, ORP composite electrode in this embodiment). Recognize the type. In order to calculate the oxidation-reduction potential Eh value, when reading the monopolar potential of the comparison electrode 2 from the table data storage unit 12 to the calculation unit 11, the table data corresponding to the type of the comparison electrode 2 is converted into temperature data. Select and read the corresponding monopolar potential. Other processing procedures are the same as those in the first embodiment.

  As mentioned above, although this invention was demonstrated according to the specific Example, it should be understood that this invention is not limited to the aspect of each said Example.

For example, in each of the above-described embodiments , the display device 14 that is a display unit that displays information indicating the measurement result is used as a unit that outputs information indicating the measurement result . However, the present invention is not limited to this. . The means for outputting the information indicating the measurement result is , for example, a print provided on the main body B or connected to the main body B so as to be communicable as a printing means for printing the information indicating the measurement result on a recording medium such as a recording paper. It may be a device. The means for outputting the information indicating the measurement result may be a transmission means for transmitting the information indicating the measurement result to a device (for example, a personal computer) connected to the oxidation-reduction potential measuring apparatus 100 so as to be communicable. . Further, the means for outputting the information indicating the measurement result can be attached to or detached from a storage medium (for example, a magnetic storage medium such as a hard disk or an electronic storage medium such as a RAM) mounted on the main body B or the main body B. It may be a writing means for writing information indicating the measurement result in a storage medium (for example, a magnetic storage medium such as a flexible disk or an electronic storage medium such as a flash memory).

  In each of the above embodiments, the measurement electrode 1 and the comparison electrode 2 are described as being integrally configured as the ORP composite electrode A, but the present invention is not limited to this configuration. The measurement electrode 1 and the comparison electrode 2 may be configured separately and connected to the main body B, respectively. When the measurement electrode 1 and the comparison electrode 2 are configured separately, the identification means described in the second embodiment is provided in the comparison electrode 2. Similarly, the temperature sensor 3 is not limited to the one provided integrally with the ORP composite electrode A, and is provided as a single body or integrally with either the measurement electrode 1 or the comparison electrode 2. It may be.

  Further, in each of the above embodiments, the description has been made assuming that the unipolar potential information storage means for storing the table data indicating the relationship between the unipolar potential of the comparison electrode and the temperature is provided in the main body. In general, by providing this storage means in a main body having sufficient space or the like, a relatively large amount of data can be stored at a relatively low cost. However, the present invention is not limited to this. For example, when the reference electrode (which may be integrated with the measurement electrode as a composite electrode) is detachable from the main body, the electrode The device itself may be provided with unipolar potential information storage means. As a result, as described in the second embodiment, the signal processing means is not provided with any means for transmitting information indicating the type of the comparison electrode, and always responds to the temperature in accordance with the type of the comparison electrode to be used. A monopolar potential can be obtained.

It is a schematic block diagram of one Example of the oxidation-reduction potential measuring apparatus which concerns on this invention. It is a flowchart figure which shows the outline of the process sequence of the oxidation-reduction potential measuring device according to this invention. It is a schematic block diagram of the other Example of the oxidation-reduction potential measuring apparatus based on this invention. It is a schematic block diagram of the other Example of the oxidation-reduction potential measuring apparatus based on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Redox potential measuring electrode 2 Reference electrode 3 Temperature sensor (temperature detection means)
10 CPU circuit (signal processing means)
11 arithmetic unit 12 table data storage unit (unipolar potential information storage means)
13 Measurement Data Storage Unit 14 Display 15 Operation Unit 20 Identification Information Storage Means

Claims (8)

In the oxidation-reduction potential measuring device having the oxidation-reduction potential measurement electrode, the comparison electrode, and the temperature detection means,
Unipolar potential information storage means for storing table data indicating the relationship between the unipolar potential of the comparison electrode and the temperature;
A single electrode potential of the comparison electrode corresponding to the output signal from the temperature detection means is obtained based on the table data, and a potential difference between both electrodes is obtained based on the output signals from the oxidation-reduction potential measurement electrode and the comparison electrode. Signal processing means for obtaining and calculating a redox potential Eh value from the potential difference and the monopolar potential;
Means for outputting information indicating the redox potential Eh value calculated by the signal processing means;
An oxidation-reduction potential measuring apparatus comprising:   2. The oxidation-reduction potential measuring apparatus according to claim 1, further comprising means for outputting information indicating the potential difference.   3. The apparatus according to claim 1, further comprising: means for shifting the potential difference by adding or subtracting a predetermined value; and means for outputting information indicating a value obtained by shifting the potential difference by the predetermined value. The oxidation-reduction potential measuring device described in 1. The single electrode potential data storage means corresponding to the plurality of comparison electrodes of different types, the oxidation-reduction potential according to any one of claims 1-3, characterized in that storing a plurality of said table data measuring device. 5. The oxidation-reduction potential measuring apparatus according to claim 4 , further comprising a transmission means for transmitting information indicating the type of the comparison electrode to the signal processing means. The transmission means is accompanied by input means for inputting information indicating the type of the comparison electrode by an operator's operation, or information indicating the type of the comparison electrode that can be attached to and detached from the signal processing means together with the comparison electrode. 6. The oxidation-reduction potential measuring device according to claim 5 , which is an identification unit. 7. The oxidation-reduction potential measuring apparatus according to claim 6 , wherein the identification unit is a storage medium that can be attached to and detached from the signal processing unit together with the comparison electrode. The oxidation-reduction potential measuring device according to any one of claims 4 to 7 , wherein the plurality of different types of reference electrodes have different internal electrodes and / or electrode internal liquids.

Images