JPH05126818A - Data processing apparatus for toc meter - Google Patents

Abstract

PURPOSE:To perform range switching automatically so as to output an analog signal in the optimum range in response to a TOC value. CONSTITUTION:The optimum calibration curve in response to the measured value is selected out of a calibration curve memory part 4 with an optimum- usable-calibration-curve judging part 5. The value of TOC is computed in an operating part 6 by using the calibration curve. The value is converted into the analog signal. The optimum range of the analog signal is determined with an optimum-analog-signal-range judging part 9. The analog signal in the determined optimum range is outputted from an analog output part 10. When the selected calibration curve is different from the calibration curve for the measured value immediately before, the measurement is performed again. When the range is switched, the switching is displayed on a recorder.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data processing device for outputting a TOC measurement value as an analog signal in a batch type TOC (total organic carbon) meter. Conventional T
In the data processing device of the OC meter, the TOC value is calculated using the calibration curve with respect to the measurement value from the detection unit, the TOC value is converted into an analog signal, and the preset one range (full scale) is used. It is outputting.

[0002]

When the analog signal is output in a fixed range, if the TOC value of the sample exceeds that range, it will exceed the full scale of the analog signal. It becomes impossible to record in total. An object of the present invention is to provide a data processing device having a function of automatically performing range switching so that the analog signal can be output in the optimum range according to the TOC value.

[0003]

The present invention will be described with reference to FIG. A measurement value storage unit 3 is provided to store the measurement value of the sample, and the calibration curve storage unit 4 stores a plurality of calibration curves according to the magnitude of the measurement value. A used calibration curve optimality determination unit 5 is provided to select the optimum calibration curve according to the measured value, and the TOC is calculated from the measured value using the selected calibration curve.
A calculation unit 6 is provided to calculate a value and convert the TOC value into an analog signal. In order to output the analog signal, an analog signal range optimality determination unit 9 that determines the optimum range of the analog signal is provided, and the analog signal is output in the optimal range determined by the analog signal range optimality determination unit 9. Therefore, the analog output unit 10 is provided.

Further, in FIG. 1, when the calibration curve selected by the calibration curve optimumness determining unit 5 is different from the calibration curve for the immediately preceding measurement value, remeasurement conditions are set and remeasurement is instructed. A measurement condition setting unit 11 is also provided. In addition, the analog output unit 10 may have a function of outputting an identification display indicating that the ranges are different when the ranges are switched.

[0005]

[Operation] When the TOC value is calculated using the optimum calibration curve for the measured value of a certain sample and the analog signal is output in the optimum range, the calibration curve for the measured value of the next sample is obtained. If is not optimal with the previous sample, a new calibration curve is selected by the used calibration curve optimality determination unit 5, and the TOC value is calculated by the calculation unit 6 based on the calibration curve. The analog signal converted from the TOC value is
If the analog signal output range of the previous sample exceeds the full scale and is not appropriate, the analog signal range optimumness determination unit 9 determines the optimum range and outputs the new range. On the contrary, even when the measured value of the next sample becomes small, the optimum calibration curve and the optimum range are determined.

When the remeasurement condition setting unit 11 is provided, the remeasurement is performed on the same sample when the measurement value is largely changed and the calibration curve is changed. When the analog output unit 10 has a function of outputting an identification display, a display is made on the recorder to indicate that the ranges are different when the ranges are switched.

[0007]

FIG. 2 shows a block diagram of an embodiment. The output of the detector 2 is MPU (micro processor unit)
Taken in 7. The MPU 7 calculates the TOC value using the optimum calibration curve, converts it into an analog signal, then selects the optimum range and outputs it from the analog output unit 10. RAM for temporarily storing measured values
The memory 8 such as is connected to the MPU 7. Comparing FIG. 1 and FIG. 2, the measured value storage unit 3 and the calibration curve storage unit 4 of FIG. 1 correspond to the memory 8 of FIG. 2, and the used calibration curve optimality determination unit 5, the calculation unit 6, and the analog of FIG. The signal range optimality determination unit 9 and the remeasurement condition setting unit 11 are realized by the MPU 7 in FIG.

FIG. 3 shows an example of a TOC meter to which the present invention is applied. The sample flows into the flow-through type sample container 12 from the lower inlet, and the sample is discharged from the upper outlet. The sample in the sample container 12 is the sample injection part 14
A fixed amount is collected by and is switched to and guided to the TC reaction unit 16 or the IC reaction unit 18. The TC reaction section 16 is provided with a TC combustion tube filled with an oxidation catalyst, and a heating furnace is provided outside the TC combustion tube to heat the TC combustion tube. To the TC reaction section 16, pure oxygen gas or high-purity air from which CO ₂ and hydrocarbons have been removed is supplied from the carrier gas supply section 20 as a carrier gas at a controlled gas flow rate.
In the TC reaction section 16, all the carbon components in the supplied sample are converted into CO ₂ gas and guided to the measurement cell of the non-dispersion type infrared gas analyzer (NDIR) 22 of the CO ₂ detection section to be detected. In the IC reaction part 18, inorganic carbon is generated as CO ₂ gas, which is guided to the measurement cell of the NDIR 22 together with the carrier gas and detected. The sample injection unit 14 is a TC or IC
The standard solution 23 can also be injected for preparing the calibration curve of the above.

In order to process the detected value of NDIR 22,
As shown in FIG. 2, the MPU 7 is provided, the MPU 7 calculates the TOC value from the TC value and the IC value, and the analog output unit 10 is connected to the MPU 7 to output the TOC value to the recorder. Has been done. Reference numeral 26 is a measurement value display / printing unit for displaying and printing the measurement values.

The operation of one embodiment will be described with reference to FIGS. 4 and 5. When the measurement of one sample is completed, it is judged whether or not the calibration curve currently used is optimum for the measured value (steps S1 → S2). If it is optimum, the TOC value is calculated using the calibration curve (step S3). Next, it is judged whether or not the analog signal range is optimum for the TOC value (step S4), and if it is optimum, the analog output value is calculated and output in that range (step S5).

If the analog signal output range is not optimum in step S4, the range is changed (step ST6). At that time, when the range is changed to a range higher than the range before the change, in order to distinguish from the output by the previous range, after outputting 0 V (4 mA), the analog output value is calculated in the changed range. Output (step S7 → S8 → S5) (see a in FIG. 5). When the changed range is lower than the range before the change, 0 V is not output (steps S7 → S5) (see b in FIG. 5). If the used calibration curve is not optimum in the determination in step S2, the calibration curve is changed to the optimum one and remeasurement is performed (steps S2 → S9). During the remeasurement, the analog signal of the measured value of the previous sample continues to be output (see b and c in FIG. 5). When the measured value becomes smaller and the range is changed to a range smaller than the range before the change, the reference is programmed so that the smaller range is output when the measured value is within 90% of the smaller range. Keep it.

As shown in FIG. 5, when the range is switched to a side larger than the range before the change, an identification display is provided so that the voltage once drops to 0 V before the analog signal of the measured value is output. On the contrary, when the range is switched to a large range, such identification display is not given. However, the identification display is not limited to such a method of lowering to 0V, and other display methods such as adding a symbol may be used.
Further, even when the range is switched to two or more steps, the distinction between the one-step switching and the two-step switching is not made in this embodiment, but such multi-step switching can be identified by different displays. Good. Further, in the embodiment, the switching of the calibration curve and the switching of the range are not necessarily made to correspond to each other, but this is made to correspond one-to-one so that the range is always switched when the calibration curve is changed. You may stay.

[0013]

As described above, according to the present invention, the operation of expanding the range of the analog signal corresponding to the TOC value of the sample or returning to the original range is automatically performed. An analog signal can be output. If you re-measure when you change the calibration curve,
More accurate measurement can be performed. If the same analog signal is used to identify that the ranges are different when the ranges are switched, the configuration will be simple, and everything can be recorded with a low-cost 1-pen recorder. It is advantageous.

[Brief description of drawings]

FIG. 1 is a block diagram showing the present invention.

FIG. 2 is a block diagram showing an embodiment.

FIG. 3 is a flow path diagram showing a TOC meter to which the present invention is applied.

FIG. 4 is a flowchart showing the operation of the embodiment.

FIG. 5 is a waveform diagram showing an output example of a recorder showing an example of the operation.

[Explanation of symbols]

 2 Detection unit 3 Measured value storage unit 4 Calibration curve storage unit 5 Used calibration curve optimality determination unit 6 Calculation unit 7 MPU 8 Memory 9 Analog signal range optimality determination unit 10 Analog output unit 11 Remeasurement condition setting unit

Front page continuation (72) Inventor Hiroaki Matsuhisa 1 Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto City, Kyoto Prefecture Shimazu Corporation Sanjo Factory

Claims (3)

[Claims] 1. A data processing device for calculating a TOC value from a measurement value of a detection unit of a batch type TOC meter and outputting an analog signal corresponding to the TOC value, a measurement value storage unit for storing the measurement value of a sample, and a measurement value. A calibration curve storage section that stores multiple calibration curves according to the size of the measurement curve, a calibration curve optimality determination section that selects the optimum calibration curve according to the measured value, and measurement using the selected calibration curve A TOC value is calculated from the calculated value and the TOC value is converted into an analog signal. An analog signal range optimality determination unit that determines the optimum range of the converted analog signal and an analog signal analog signal range optimality determination A data processing device having an analog output section for outputting in an optimum range determined by the section. 2. A re-measurement condition setting unit for setting re-measurement conditions and instructing re-measurement when the calibration curve selected by the used calibration curve optimality determination unit is different from the calibration curve for the immediately preceding measurement value. The data processing apparatus according to claim 1, further comprising: 3. The data processing device according to claim 1, wherein the analog output section also outputs an identification display indicating that the range is different when the range is switched.