JP6166857B2 - Method for generating calibration data for thermometer, storage device storing calibration data, and thermometer employing this method - Google Patents

Description

The present invention relates to a thermometer calibration method and a thermometer employing this calibration method, and in particular, refers to calibration data indicating the temperature characteristics received from a digital output of a digital probe of the thermometer and stored in a predetermined storage device. The present invention relates to a thermometer calibration method for generating a display temperature, a storage device storing calibration data, and a thermometer employing this method.
Here, the digital probe is used as a term indicating a sensor unit that converts the output of the heat sensitive element into a digital signal and outputs the digital signal.

In calibration, the output of the target thermometer at two temperatures obtained using a predetermined reference thermometer is measured, and an approximate curve representing the relationship between the temperature and the thermometer output is generated, and this is used as the target thermometer. Generally, a method of adjusting the accuracy by incorporating it has been performed.

Regarding the uncertainty, the calibration certificate issued by a normal calibration organization describes that the error is ± 0.1 for each measurement point, but it is unclear between the measurement points. In the conventional calibration method, the accuracy of all the characteristic curves is fitted with a first-order straight line, a quadratic curve, a third-order, a fourth-order, etc., and an approximate expression count based on knowledge about the characteristics coming from the probe material. There is a problem of just letting it.

Patent Document 1 relates to a method of calibrating a thermocouple using a cryogenic liquid (for example, liquid oxygen, liquid nitrogen, etc.). Again, a thermocouple is inserted into the actual liquid in an open air state, the temperature and electromotive force are measured, and the temperature at 0 ° C. is measured using a 0 ° C. reference temperature device, and the two points are connected by a straight line. The following method is proposed by pointing out the problem that the method is generally used.
That is, a cryogenic liquid is filled in an insulated container, a thermocouple is inserted into the cryogenic liquid, and the same kind of gas as the cryogenic liquid is controlled to be injected into the cryogenic liquid filled in the container. To create an arbitrary liquid temperature and a saturated vapor pressure corresponding to the liquid temperature, and obtain calibration data from a cryogenic liquid temperature corresponding to the saturated vapor pressure and an electromotive force of a thermocouple thermometer Is. By repeating the procedure of obtaining an arbitrary liquid temperature and a saturated vapor pressure corresponding to the liquid temperature by controlling the amount of gas injected into the cryogenic liquid and the amount of gas released from the container, A saturated vapor pressure can be created from 0 atm to an arbitrary pressure, a cryogenic liquid having various temperatures can be obtained, a large amount of calibration data can be obtained, and a highly accurate calibration curve can be obtained.
However, the method of Patent Document 1 has a problem that it is limited to a temperature range obtained from a cryogenic liquid at a predetermined saturated vapor pressure.
Japanese Patent No. 2990276

An object of the present invention is to perform many measurements over the entire measurement range of a thermometer to be calibrated. An object of the present invention is to provide calibration data in place of a temperature characteristic curve generated by curve fitting based on measurement values at a small number of measurement points.
That is, it is to provide a calibration table that enables continuous measurement with a sufficiently small temperature range with respect to the temperature scale and that can extract the temperature to be displayed by the thermometer simply by referring to it. .

In the first aspect of the present invention,
1) Temperature control for forming a step-like temperature curve for setting a follow-up waiting time for the digital probe to follow after temperature control of a thermostat housing a digital probe and a standard device of a thermometer to be calibrated Temperature control according to a program including :
2) continuously recording the digital output of the digital probe in association with the measured temperature of the standard device during the temperature control;
3) executing an uncertainty estimation calculation including, as a parameter, a value obtained by digitizing a temperature characteristic including an uncertainty value resulting from the follow-up waiting time;
4 ) generating a calibration table including the uncertainty generated by the uncertainty estimation calculation, the value of the digital output and a calibration value for calibrating the value to the measured temperature;
A method for generating a calibration table is provided .

The recording may be executed at least once for each of a plurality of small sections obtained by dividing a temperature graph formed by the temperature control .
If the small section is set short, sampling is performed at a high frequency, and the digital output recorded in this way is recorded on the x-axis and the recording point when the measured temperature is taken on the y-axis (sensor output, measured temperature). The curve connecting the two can be substituted for the temperature characteristic curve of the digital probe.
Here, since the setting of the x-axis and the y-axis is arbitrary, it can be appropriately adopted according to the configuration of the calibration table. By setting the small section appropriately, there is an effect that a more accurate curve can be obtained than the conventional approximate curve generated from two characteristic points.

The recording may be performed continuously at a predetermined measurement cycle.
If sampling is performed with a short measurement cycle, the curve connecting the recorded points (digital output, measured temperature) when the digital output recorded in this way is taken on the x-axis and the measured temperature is taken on the y-axis is the temperature of the digital probe. A characteristic curve can be substituted.

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The value of the digital output related to the recording is a value generated by estimation from the tracking standby time and the digital output at the time of recording, and the parameter of the uncertainty estimation calculation is an uncertainty caused by the tracking standby time and the estimation. It is also possible to include the value of the height.

The follow-up waiting time may be set to a time required to keep the uncertainty value within a predetermined range.
By setting the minimum time required to realize the desired uncertainty as the follow-up waiting time, there is an effect of reducing the time required for the calibration work.

There may be a plurality of the standard devices, and the method may further include a step of deriving a temperature characteristic parameter of the thermostatic bath from a difference between measured temperatures of the plurality of standard devices corresponding to the measurement.

The inference may be derived by applying to a model of tracking characteristics prepared in advance or a temperature graph.

The value of uncertainty due to the follow-up waiting time and the guess may be derived with reference to a correspondence table of follow-up waiting time / uncertainty prepared in advance.

You may provide the memory | storage device which stored the calibration table produced | generated by the said production | generation method.
The thermometer user can carry out a work method in which the storage device is carried out together with the digital probe to the calibration place, the calibration data generated by the calibration work is written in this storage device, and returned to the thermometer user. This has the effect of making the entire operation simple and efficient.

A thermometer that includes display temperature generation means as a constituent element that refers to the calibration table generated by the above generation method, extracts a measurement temperature corresponding to the digital output of the digital probe, and generates a display temperature from the measurement temperature May be provided.

The thermometer may include a calibration result fetching unit that reads a calibration table stored in the storage device and sets the calibration table in the reference table.

In the thermometer, quality control may be performed by calculating time-series degradation of the thermometer from time-series data of calibration values stored in the storage device.
It shows the change of the thermometer over time, and has the effect of helping to manage the deteriorated thermometer.

Thermometer according to Example 1 Configuration of the main unit Digital probe configuration Conceptual diagram of calibration facility Flow chart of work related to calibration Temperature control and recording flowchart Temperature curve Measurement points by sampling with a set period Calibration table contents Recording point plot mode Display temperature generation flowchart Thermometer according to Example 2 Conceptual diagram of calibration facility Flow chart of work related to calibration Temperature control and recording flowchart Temperature curve

Hereinafter, specific examples of the present invention will be described with reference to the drawings.

FIG. 1 is an external view of a thermometer according to the first embodiment. Thermometer main body 1001, first measurement location 1002, RFID card 1003 which is a storage device corresponding to the first measurement location, second measurement location 1004, RFID card which is a storage device corresponding to the second measurement location 1005, a third measurement location 1006, and an RFID card 1007 which is a storage device corresponding to the third measurement location. The equipment configuration at each measurement location is the same. That is, as shown in the third place, there are three digital probes 1008a, 1008b, 1008c, a line terminator 1009 for connecting the digital probe to the communication line of the thermometer body, and an RFID reader 1010 connected to the terminator. . Here, each measurement place is configured to have three digital probes, but the thermometer according to the present invention is not limited to this, and can be appropriately changed according to the temperature measurement target and the thermometer installation site. . In addition, the digital probe associated with each measurement location is detachably electrically connected to the termination device. The RFID card is a portable storage device that stores calibration data and calibration execution commands.

FIG. 2 is a block diagram showing the internal configuration of the thermometer main body 1001.
The display temperature generating unit 2001, the main body memory 2002, the calibration result fetching unit 2003, and the display unit 2004 are configured.

The display temperature generation unit 2001 receives a digital output from a digital probe connected via a termination device, and generates a display temperature with reference to a calibration table stored in the main body memory 2002. When the received output does not match the recording point described in the table, the display temperature is set with reference to a straight line connecting the recording points sandwiching the received output.
The calibration table will be described later.

When the RFID card corresponding to the digital probe is brought close to a predetermined RFID reader, the calibration result fetching means 2003 rewrites the calibration table stored in the main body memory with the calibration data in accordance with the stored calibration execution command. Executed.
Here, the calibration table before rewriting is stored in the main body memory as past data without being erased. Calculate the time-series deterioration of the thermometer from the time-series data of the calibration values from the past to the present, and when the calibration value becomes larger than a certain range, discard the corresponding digital probe and replace it with a new one Perform quality control such as

The display means 2004 is composed of a display device such as a liquid crystal and displays the display temperature generated by receiving the outputs from the first to third measurement locations.
Further, a calibration table stored in each storage device corresponding to the first to third measurement locations, or a document proving the legacy of the standard device used for calibration may be displayed. Conventionally, the accuracy management of the thermometer can be easily confirmed by digitizing and storing a document that has been issued in paper accompanying the calibration work and checking it on site.

Each means shown here is realized by executing a control program such as firmware incorporated in advance by a processor of a control circuit and cooperating with various devices mounted. These programs are recorded on a computer-readable recording medium, read from the recording medium by the processor, and executed by a user operation or receiving a signal from a device constituting a controller. .

FIG. 3 shows the configuration of the digital probe 1008.
The digital-analog converter 3001 connected to the line terminator and the probe 3002 for sending a signal by sensing the temperature of the measurement target.
The digital-analog converter 3001 converts an analog signal from the probe into a digital output and sends it as a digital output.

FIG. 4 is a conceptual diagram of the calibration facility. Here, the three digital probes that have been installed at the third measurement location are to be calibrated.
A thermostat 4001, a thermal controller 4002 for controlling temperature control of the thermostat, standard thermometers 4003 and 4004 connected to a thermal controller serving as a calibration target standard, a server 4005 connected to the thermal controller, a third calibration target The configuration includes a digital probe 1008a, 1008b, 1008c at a measurement location, a line terminator 4006 connected to three digital probes connected in a daisy chain, and an RFID reader / writer 4007 connected in communication with a server. Here, the RFID card 1007 corresponding to the third measurement location is brought close to the RFID reader / writer 4007 after the calibration work is completed, and calibration data is written.

The operation of the thermal controller and server shown here is realized by executing a control program such as firmware incorporated in advance by a processor of the control circuit and cooperating with various devices such as a mounted heater and cooler. . These programs are recorded on a computer-readable recording medium, read from the recording medium by the processor, and executed by a user operation or receiving a signal from a device constituting a controller. .

FIG. 5 is a flowchart showing work / operations related to calibration.
In step 5001, the user removes the sensor unit and carries it out to the calibration facility. The only items to be carried out here are the digital probes 1008a, 1008b, 1008c at the third measurement location to be calibrated and the RFID card 1007 corresponding thereto.
Since the other sensor units and the main body can be left at the measurement place, there is an effect that the complexity of carrying out is greatly reduced. In addition, the measurement can be continued at points other than the calibration points, which contributes to the continuity of the measurement work.

In step 5002, the calibration person stores the three digital probes at predetermined measurement positions in the thermostat. In FIG. 4, it is housed in a mode of being set between two standard thermometers, but the measurement position of the present invention is not limited to this, so that the digital probe and the standard thermometer have a close temperature environment. If it is a position in consideration, it can be adopted as appropriate.

In step 5003, temperature control by a program of the thermal controller, and recording in association with the output from the standard thermometer serving as the control temperature and the value of the digital output from the digital probe are performed.
FIG. 6 is a flowchart showing the temperature control and recording procedure.
When started, the temperature control of the thermostat is performed, and the inside of the thermostat is controlled so as to draw a predetermined temperature curve according to the above-mentioned program.
In step 6001, the measurement point 1 is recorded. Subsequently, in step 6002, the measurement point 2 is recorded. Thereafter, recording is performed n times for the number of measurement points x set as shown in 6003, and recording is repeated until recording in the measurement section n shown in 6004.

FIG. 7 shows the temperature curve adopted here in terms of the relationship between time and control target temperature.
Here, the temperature of the recording target is 45 ° C. to 90 ° C. This measurement section is divided into n sections such as a small section 1 denoted by 7002, a small section 2 denoted by 7002, a plurality of small sections x denoted by 7004, and a small section n denoted by 7005.
P1 is a measurement point 1 provided in a small section indicated by 7002. P2 is a measurement point 2 provided in a small section indicated by 7003. A plurality of measurement points x indicated by Px continue and are set up to the nth measurement point Pn.

Here, as shown in FIG. 8, it is also possible to adopt a method in which sampling is performed by setting a cycle so that continuity of recording levels at least once is obtained in a small section. In the temperature curve 8001, if recording is continuously performed with a sufficiently small period 8003 in the temperature control execution time 8002 corresponding to the temperature range of 45 to 90 degrees in the recording target, the measurement point Px has a temperature range in a small section. This is data in which the temperature characteristics are finely plotted in the same manner as divided into two.

In step 6005, the operation of the server 4005 performs a calculation for correcting the correspondence between the standard thermometer output and the digital output based on the difference in temperature followability between the predetermined standard thermometer and the digital probe to be calibrated. Here, for the difference in temperature follow-up, it is sufficient to use a value confirmed in the specifications and tests of the product.
In order to measure the temperature correctly, it is usually necessary to wait for the temperature of the standard thermometer and the temperature of the digital probe to equilibrate. The mode of temperature change until the temperature of both reaches equilibrium is applied to a predetermined equation to predict the equilibrium point. Based on this prediction, the output of the digital probe corresponding to the output of the standard thermometer is estimated at high speed. Then, the estimated output of the digital probe is used as a digital output for recording.
Further, in step 6006, the measurement temperature / uncertainty calculation at each measurement point is performed by the operation of the server 4005.
The measured temperature is the arithmetic average of the outputs from the two standard thermometers.
Uncertainty is indicated by the sum of the temperature control uncertainty of the thermostatic chamber indicated by the difference between the decomposition ability of the standard thermometer and the output from the plurality of standard thermometers.
Further, here, the calculation is performed in a batch processing after all the recording is completed, but a method of calculating sequentially for each recording can also be adopted.

Here, the measurement temperature for each measurement point is recorded in association with the digital output of the digital probe estimated.
Note that the temperature pattern 7001 shown in FIG. 7 is merely an example, and when the heat capacity of the thermostatic chamber has a sufficient margin, a measurement section is set as a steep temperature pattern, and the standard unit is set at a shorter interval between these intervals. A method may be used in which sampling of the output and the digital output is performed to obtain data in which the digital output is associated with the measured temperature.

Returning to FIG. In step 5004, calibration result data is generated from the acquired data by the operation of the server.
FIG. 9 shows the contents of the calibration table using the recording in the temperature control of FIG. A calibration result of the measurement point P1 in the small section 1 indicated by 9001, a calibration result of the measurement point P2 indicated by 9002, a calibration result of the measurement point Px indicated by 9003, and a calibration result of the measurement point Pn indicated by 9004. For each measurement point, digital output 9005, measurement temperature 9006, calibration value 9007, and uncertainty 9008 are stored.

The recording points (digital output, measurement temperature) indicated by the digital output 9005 and the measurement temperature 9006 associated with each measurement point are continuously acquired in a sufficiently short section to generate a display temperature after calibration. As a digital output / temperature characteristic curve, it can be used for display temperature generation in a thermometer to be calibrated.
FIG. 10 shows the recording coordinates at the measurement points shown in FIG. 7 with circles, with the digital output 10001 as the x-axis and the measurement temperature 10002 as the y-axis. If the measurement interval is sufficiently narrow, it is clear that the temperature characteristic curve itself of the digital probe is represented.
If there is no record corresponding to a digital output, average the measured temperatures of the records on both sides of that value, or take a reference point on a straight line connecting the points on both sides and substitute for that digital output record. That's fine.
When sampling is performed in three or more small sections, there is an effect that a display temperature can be generated with higher accuracy than the conventional approximate curve generated by recording two points. In particular, when a small section having a sufficiently short length of the resolution level of the thermometer serving as a standard is set, calibration with the maximum degree of accuracy possible with the calibration facility of the embodiment can be performed.
In the case of adopting a method of measuring temperature at a predetermined cycle, if the cycle is set so short that the temperature difference between adjacent measurement points becomes the resolution level of the thermometer as a standard device, the calibration equipment of the embodiment A calibration with the maximum possible accuracy is possible.

Here, in addition to the calibration table, a certificate proving legacy from an international standard of a standard thermometer or the like may be stored as calibration data.

Step 5005 is a step of storing the calibration table by the server 4005 in the memory. Here, the calibration person operates the server 4005, transmits a write instruction from the server, and causes the RFID reader / writer 4007 to perform a writing operation, thereby making the calibration data of the RFID card 1007 close to the calibration person close. A calibration table is stored as a configuration.

In step 5006, the digital probe and the RFID card are returned by the calibration staff.
In step 5007, the digital probe is attached by the user.
In step 5008, when the RFID card returned from the calibration location is brought close to the RFID reader at the measurement location, a calibration execution command stored in advance in the RFID card is transmitted to the thermometer main body 1001, and the calibration result capturing means 2003 By the operation, the calibration table stored in the main body memory 2002 is rewritten to the calibration table stored in the RFID tag.

FIG. 11 is a flowchart of an operation in which the thermometer main body generates a display temperature using the calibration table as a reference destination.
In step 11001, a digital output from the digital probe to be measured is acquired.
Next, in step 11002, the calibration table stored in the main body memory is referred to. That is, the digital output registered in the calibration table is compared with the output value from the digital probe, and a matching recording point is searched.
If there is a coincident recording point, the process moves to step 11003, and the measurement temperature constituting the recording point is set as the measurement target temperature, that is, the display temperature, and the process ends.
On the other hand, if there is no coincident recording point, the process moves to step 11004 to extract recording points indicating the upper and lower values sandwiching the output from the digital probe.
In step 11005, the average of the measured temperatures corresponding to the two extracted recording points is generated as the display temperature, and the process ends.

  Here, when the recording point that matches the digital output cannot be extracted from the calibration table, a method was adopted in which the average of the measured temperatures corresponding to the recording points indicating the upper and lower values sandwiching the output of the digital probe is used as the display temperature. The display temperature generation according to the invention is not limited to this, and can be appropriately adopted, for example, by adopting a method of searching for a measurement temperature that matches the output from the digital probe on a curve connecting recording points.

The second embodiment will be described with a focus on differences from the first embodiment.
FIG. 12 is an external view of a thermometer according to the second embodiment. Thermometer main body 12001, first measurement location 12002, RFID card 12003 which is a storage device corresponding to the first measurement location, second measurement location 12004, RFID card which is a storage device corresponding to the second measurement location The configuration includes 1205, a third measurement location 12006, and an RFID card 12007 which is a storage device corresponding to the third measurement location. The equipment configuration at each measurement location is the same. That is, as shown in the third place, there are three digital probes 12008a, 12008b, 12008c, a line terminator 12009 for connecting the digital probe to the communication line of the thermometer body, and an RFID reader 12010 connected to the terminator. . Here, each measurement place is configured to have three digital probes, but the thermometer according to the present invention is not limited to this, and can be appropriately changed according to the temperature measurement target and the thermometer installation site. . In addition, the digital probe associated with each measurement location is detachably electrically connected to the termination device. The RFID card is a portable storage device that stores calibration data and calibration execution commands.

The configurations of the thermometer main body and the digital probe are the same as those in the first embodiment.

FIG. 13 is a conceptual diagram of the calibration facility. Here, the three digital probes that have been installed at the third measurement location are to be calibrated.
A thermostat 13001, a thermal controller 13002 for controlling the temperature control of the thermostat, standard thermometers 13003 and 13004 connected to a thermal controller as a calibration target standard, a server 13005 connected to the thermal controller, a third calibration target The configuration includes a digital probe 12008a, 12008b, 12008c at a measurement location, a line terminator 13006 connected to three digital probes connected in a daisy chain, and an RFID reader / writer 13007 connected to a server. Here, the RFID card 12007 corresponding to the third measurement location is brought close to the RFID reader / writer 13007 after the calibration work is completed, and calibration data is written.

The operation of the thermal controller and server shown here is realized by executing a control program such as firmware incorporated in advance by a processor of the control circuit and cooperating with various devices such as a mounted heater and cooler. . These programs are recorded on a computer-readable recording medium, read from the recording medium by the processor, and executed by a user operation or receiving a signal from a device constituting a controller. .

FIG. 14 is a flowchart showing work / operations related to calibration.
In step 14001, the user removes the sensor unit and carries it out to the calibration facility. The only items to be carried out here are the digital probes 12008a, 12008b, 12008c at the third measurement location to be calibrated and the RFID card 12007 corresponding thereto.

In step 14002, the calibration person stores the three digital probes in the predetermined measurement position of the thermostat as in the first embodiment.

In step 14003, temperature control by a program of the thermal controller, and recording in association with the output from the standard thermometer serving as the control temperature and the estimated value of the digital output from the digital probe are performed.
FIG. 15 is a flowchart showing the temperature control and recording procedure.
When started, the temperature control of the thermostat is performed, and the inside of the thermostat is controlled so as to draw a predetermined temperature curve according to the above-mentioned program.

In step 15001, measurement point 1 is recorded.
Subsequently, at step 15002, the measurement point 2 is recorded. Thereafter, the recording step of the number n of measurement points x set as shown in 15003 is repeatedly performed, and recording is repeated until recording in the measurement section n shown in Step 15004.

FIG. 16 shows a temperature curve of a thermostatic chamber whose temperature is controlled by the program adopted here in relation to time and control temperature.
Here, 16001 is the place where the control temperature of the first measurement was controlled to 45 degrees. Reference numeral 16002 denotes a follow-up waiting time for keeping the temperature constant. Recording of measurement point 1 is performed at the time of 16003 after the elapse of time, that is, the timing of P1 (16004).
Similarly, the control temperature for the next measurement is controlled, the temperature is kept constant, and measurement / recording is performed at the timing of P2 (16005) after the follow-up waiting time has elapsed. Thereafter, the temperature is controlled to the control temperature for the next measurement, the temperature is kept constant, measured and recorded at the timing Px (16006) after the follow-up standby time has elapsed, and further controlled to the next control temperature, and so on. The temperature control is performed.
Here, the temperature is raised to the set temperature of 90 degrees, the temperature is kept constant, and the process is repeated until the timing Px (16007) after the follow-up waiting time has elapsed.
If you set the time to be constant enough, the correction of the deviation due to the difference in temperature follow-up is unnecessary or minimized, which has the effect of improving the measurement accuracy, but here the calibration time is shortened and the calibration work is reduced. Digital probe when reaching the control temperature starting from the measured value after the elapse of the predetermined follow-up waiting time, using an equation or temperature graph representing the temperature follow-up characteristic model of the digital probe that has been tested and created in advance to improve efficiency Guess the output of.

If recording is continuously performed at sufficiently small temperature intervals in the temperature control execution time (Pn−P1) corresponding to the temperature range of 45 ° to 90 ° to be recorded, the measurement point Px is a fine plot of the temperature range. The data substantially represents the temperature characteristic curve of the digital probe.

In step 15005, the operation of the server 4005 calculates the uncertainty of the estimation of the output of the digital probe estimated here corresponding to the control temperature at each measurement point.
Uncertainty is obtained by summing the following individual uncertainty values:
The first is the decomposition ability of the standard thermometer. Next, it is the uncertainty of the temperature control of the thermostat which the difference of the output from several standard thermometers shows. Further, it is the uncertainty obtained by referring to the follow-up waiting time / uncertainty table created by testing the digital probe in advance.
Conversely, it is also possible to set the follow-up waiting time in order to bring the sum of the uncertainty values into a desired range. Minimizing the follow-up waiting time while keeping the uncertain value required for quality control has the effect of shortening the time required for calibration and making calibration work more efficient.
Further, here, the uncertainty estimation employs a method in which all the recordings are completed and then executed collectively in a badge process, but a method of sequentially calculating each recording can also be employed.

Returning to FIG. In step 14004, the measured temperature for each measurement point is associated with the digital output of the estimated digital probe by the operation of the server, and the calibration value and the value based on the uncertainty estimate are added to create a calibration table.
The aspect of the calibration table is the same as in the first embodiment.

Here, in addition to the calibration table, a certificate proving legacy from an international standard of a standard thermometer or the like may be stored as calibration data.

Step 14005 is a step of storing the calibration table by the server 13005 in the memory. Here, the calibration person operates the server 13005, transmits a write instruction from the server, and causes the RFID reader / writer 13007 to perform a write operation, thereby making the calibration data of the RFID card 12007 close to the calibration person close. A calibration table is stored as a configuration.

In step 14006, the calibration staff returns the sensor unit and the RFID card.
In step 14007, the sensor unit is attached by the user.
In step 14008, when the RFID card returned from the calibration location is brought close to the RFID reader at the measurement location, the calibration execution command stored in advance in the RFID card is transmitted to the thermometer main body 12001 and the operation of the calibration result capturing means is performed. As a result, the calibration table stored in the RFID tag is rewritten to the calibration table stored in the RFID tag.

The operation of generating the display temperature by the thermometer main body is the same as in the first embodiment.

In the present invention, the industries that require precise accuracy control cover a wide range of fields such as the food industry, the pharmaceutical industry, and the precision machinery industry. In any industry, the method and thermometer of the present invention can be applied.

1006 Third measurement location 1007 RFID card 1008 Digital probe 4001 Thermostatic bath 4002 Thermal controller 4003 Standard thermometer 4004 Standard thermometer 4005 Server 4006 Server side line termination terminal

Claims (12)

1) Temperature control for forming a step-like temperature curve for setting a follow-up waiting time for the digital probe to follow after temperature control of a thermostat housing a digital probe and a standard device of a thermometer to be calibrated Temperature control according to a program including :
2) continuously recording the digital output of the digital probe in association with the measured temperature of the standard device during the temperature control;
3) executing an uncertainty estimation calculation including, as a parameter, a value obtained by digitizing a temperature characteristic including an uncertainty value resulting from the follow-up waiting time;
4 ) generating a calibration table including the uncertainty generated by the uncertainty estimation calculation, the value of the digital output and a calibration value for calibrating the value to the measured temperature;
A method for generating a calibration table, comprising: The generation method according to claim 1, wherein the recording is executed at least once for each of a plurality of small sections obtained by dividing a temperature graph formed by the temperature control. The generation method according to claim 1, wherein the recording is continuously performed at a predetermined measurement period. The value of the digital output related to the recording is a value generated by estimation from the tracking standby time and the digital output at the time of recording, and the parameter of the uncertainty estimation calculation is an uncertainty caused by the tracking standby time and the estimation. The generation method according to claim 1 , wherein the generation value is included. 2. The generation method according to claim 1 , wherein the follow-up waiting time is set to a time necessary for the uncertainty value to fall within a predetermined range. 2. The method according to claim 1 , further comprising a step of deriving a temperature characteristic parameter of the thermostatic bath from a difference in measured temperatures of the plurality of standard devices corresponding to the measurement, wherein the standard device includes a plurality of standard devices. Generation method. The generation method according to claim 4 , wherein the estimation is derived by applying to a model of a follow-up characteristic or a temperature graph prepared in advance. 5. The generation method according to claim 4 , wherein the value of uncertainty resulting from the follow-up waiting time and the estimation is derived by referring to a correspondence wait time / uncertainty correspondence table prepared in advance. A storage device storing a calibration table generated by the generation method according to claim 1 . A display for referring to the calibration table generated by the generation method according to claim 1 , extracting a measured temperature corresponding to the digital output of the digital probe, and generating a display temperature from the measured temperature. A thermometer comprising temperature generating means as a component. The reading of the calibration table stored in the storage device according to claim 9, in claim 10, characterized in that it comprises as a component a calibration result capturing means for setting the table according to the calibration table to the reference The thermometer described. The thermometer according to claim 11 , wherein quality control is performed by calculating time-series deterioration of the thermometer from time-series data of calibration values stored in the storage device.