JP3067640B2 - TOC meter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a batch TOC meter (total organic carbon measuring device), and more particularly to a data processing device provided in a TOC meter for outputting a TOC measured value as an analog signal.

[0002]

2. Description of the Related Art In a conventional TOC meter data processing device, a TOC value is calculated using a calibration curve for a measured value from a detection unit, and the TOC value is converted into an analog signal and set in advance. The output is displayed in one range (full scale).

[0003]

When an analog signal is output in a fixed range, the TOC value of the sample exceeds the full scale of the analog signal when the TOC value exceeds the range. It will not be possible to record in total. Further, since the TOC meter outputs the TOC value of the sample at only one point as its output, it is not possible to immediately judge whether the range has been switched just by looking at the result recorded in the recorder.

According to the present invention, range switching is automatically performed so that an analog signal can be output in an optimum range according to the TOC value, and it can be immediately judged from the display of the recorder that range switching has been performed. It is an object of the present invention to provide a TOC meter having a data processing device having a function to make

[0005]

In order to achieve the above object, in a data processing apparatus for a TOC meter according to the present invention, when a range is switched, an analog output section of the TOC meter indicates that the range has been changed. The identification display is performed by temporarily setting the output signal to 0 value.

[0006] By the output unit displaying the 0 value once,
The display on the recorder or the like can clearly display the break at the time of the switching, and the measurer can easily recognize that the range has been switched. It is possible to realize the present invention by using an inexpensive one-pen recorder without using a separate recording member such as a pen.

Hereinafter, a data processing apparatus according to the present invention will be described with reference to FIG.

A measured value storage section 3 is provided for storing the measured values of the samples, and a plurality of calibration curves corresponding to the magnitudes of the measured values are stored in the calibration curve storage section 4. A use calibration curve optimality determining unit 5 is provided to select an optimal calibration curve according to the measured value, and calculates a TOC value from the measured value using the selected calibration curve, and converts the TOC value into an analog signal. For this purpose, a calculation unit 6 is provided. In order to output an analog signal, the analog signal is output in the optimum range determined by the analog signal range optimumness determination unit 9 that determines the optimum range of the analog signal, and when the range is switched, the range is different. An analog output unit 10 for outputting a 0V value once is provided to indicate the following.

FIG. 1 further shows that if the calibration curve selected by the used calibration curve optimumness judgment section 5 is different from the calibration curve for the immediately preceding measurement value, re-measurement conditions are set and re-measurement is instructed. A condition setting unit 11 is also provided.

[0010]

When a TOC value is calculated using an optimum calibration curve for a measured value of a sample and the analog signal is output in an optimum range, a calibration curve for the measured value of the next sample is obtained. Is not optimal for the previous sample, a new calibration curve is selected by the use 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 output range of the previous sample does not exceed the full scale and is not appropriate, the analog signal range optimality determining unit 9 determines the optimum range and outputs the new range. Conversely, even when the measured value of the next sample becomes smaller, the optimal calibration curve and the optimal range are determined.

When the re-measurement condition setting unit 11 is provided, when the measured value changes greatly and the calibration curve is changed, re-measurement is performed with the same sample.

When the output range is changed, the analog output section 10 outputs a 0V value to clearly show the effect to the measurer. By displaying the 0 value once by the output unit, the display on the recorder or the like can clearly display the break at the time of the switching, and the measurer can easily recognize that the range has been switched, In addition, according to this identification display method, the recording can be realized by an inexpensive one-pen recorder without the need for a separate recording member such as a pen for the identification display.

[0013]

FIG. 2 is a block diagram of a data processing apparatus according to one embodiment.

The output of the detecting section 2 is taken into an MPU (microprocessor unit) 7. The MPU 7 calculates the TOC value using the optimal calibration curve, converts the TOC value into an analog signal, selects the optimal range, and outputs the selected range from the analog output unit 10. A memory 8 such as a RAM for temporarily storing measured values is connected to the MPU 7.

1 and 2, the measured value storage unit 3 and the calibration curve storage unit 4 in FIG. 1 correspond to the memory 8 in FIG.
1 is realized by the MPU 7 of FIG. 2.

FIG. 3 shows a TOC meter according to one embodiment.

The sample flows into the flow-type sample container 12 from below, and is discharged from the upper outlet. A certain amount of the sample in the sample container 12 is collected by the sample injection unit 14, and the sample is switched to the TC reaction unit 16 or the IC reaction unit 18 and guided. 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. Pure oxygen gas or high-purity air excluding CO2 and hydrocarbons is supplied from the carrier gas supply unit 20 to the TC reaction unit 16 at a controlled gas flow rate as a carrier gas.
In the TC reaction section 16, all of the carbon components in the supplied sample are converted into CO2 gas and guided to the measurement cell of the non-dispersive infrared gas analyzer (NDIR) 22 in the CO2 detection section for detection. In the IC reaction section 18, inorganic carbon is generated as CO2 gas and guided to the measurement cell of the NDIR 22 together with the carrier gas to be detected. The sample introduction unit 14 is provided with a TC or I
The standard solution 23 can also be injected for preparing the calibration curve of C.

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

The operation of the embodiment will be described with reference to FIGS.

When the measurement of one sample is completed, it is determined whether the currently used calibration curve is optimal for the measured value (steps S1 → S2). If it is optimal, the TOC value is calculated using the calibration curve (step S
3). Next, it is determined whether or not the analog signal range is optimal for the TOC value (step S4). If the analog signal range is optimal, an analog output value is calculated and output in that range (step S5).

If the analog signal output range is not optimal in step S4, the range is changed (step S6). At this time, if the range is changed to a range higher than the range before the change, the analog output value is calculated in the changed range after outputting 0 V (4 mA) once to distinguish the output from the previous range. And output (step S
7 → S8 → S5) (see FIG. 5A). If the changed range is lower than the range before the change, 0V is not output (step S7 → S5) (see b in FIG. 5).

If the used calibration curve is not optimal in the judgment in step S2, the calibration curve is changed to the optimal one and the measurement is performed again (step S2 → S9). During the re-measurement, the analog signal of the measured value of the previous sample is continuously output (see b and c in FIG. 5).

As a reference for the case where the measured value is reduced and the range is changed to a range smaller than the range before the change, if the measured value is within 90% of the small range, the smaller range is output. To be programmed.

As shown in FIG. 5, when the range is switched to a range larger than the range before the change, the identification display is performed so that the voltage temporarily drops to 0 V before the output of the analog signal of the measured value. Conversely, when the range is switched to a small range, such identification display is not performed.

In the embodiment, the switching of the calibration curve and the switching of the range do not always correspond to each other. However, the switching is made to correspond one-to-one so that the range can be switched whenever the calibration curve is changed. You may keep it.

[0026]

According to the present invention, the operation of expanding the range of the analog signal in accordance with the TOC value of the sample or returning to the original range is automatically performed.
An accurate analog signal can be output in a wide range. When the range is switched, an identification display indicating that the range is different is also output, so that the TOC output value recorded on the recorder is not erroneously read.
Also, since the identification display is realized by the output unit once displaying the zero value before the output of the analog signal of the measured value, the display on the recorder or the like clearly displays the break at the time of the switching. The operator can easily recognize that the range has been switched, and at the same time, does not require a separate recording member such as a pen for identification and display, and is an inexpensive one-pen recorder or the like. Thus, both the display of the output value and the identification display of the range switching can be displayed, so that the configuration of the apparatus is simplified and the apparatus cost is also advantageous.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a data processing device according to the present invention.

FIG. 2 is a block diagram illustrating a data processing device according to one embodiment.

FIG. 3 is a flow chart showing a TOC meter according to one embodiment.

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

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

[Explanation of symbols]

 2 Detector 3 Measured value storage 4 Calibration curve storage 5 Used calibration curve optimality judging unit 6 Operation unit 7 MPU 8 Memory 9 Analog signal range optimality judging unit 10 Analog output unit 11 Re-measurement condition setting unit

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Hiroaki Matsuhisa 1 Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto Shimazu Seisakusho Sanjo Plant (58) Field surveyed (Int.Cl. ⁷ , DB name) G01N 31/00 G01N 33/18

Claims (2)

(57) [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, wherein the data processing device stores a measurement value of a sample. A measurement value storage unit, a calibration curve storage unit that stores a plurality of calibration curves according to the magnitude of the measurement value, a use calibration curve optimality determination unit that selects an optimal calibration curve according to the measurement value, and a selection. From the measured values using the calibrated calibration curve
An arithmetic unit that calculates an OC value and converts the TOC value into an analog signal, an analog signal range optimumness determining unit that determines an optimum range of the converted analog signal, and an analog signal range optimumness determining unit that converts the analog signal. And an analog output section for outputting in the determined optimum range. When the range is switched, the analog output section indicates the change of the range by setting an output signal to a zero value once to indicate the identification. TOC meter characterized by performing. 2. The data processing apparatus according to claim 1, wherein the calibration curve selected by the use calibration curve optimality determining unit is different from the calibration curve for the linear measurement value, and the measurement conditions are set again to instruct re-measurement. The TOC meter according to claim 1, further comprising a re-measurement condition setting unit.