JPS5954949A - Water quality meter - Google Patents

Abstract

PURPOSE:To make it possible to accurately measure the quality of water by such an arrangement wherein the results of calibration of zero and span are fed back to an arithmetic operation circuit every time when a calibration is made, and the constants of an arithmetic operation formula are renewed and compensated. CONSTITUTION:Every time a period of time set by a timer has elapsed, change-over switches 32a, 32b are changed over to the side of calibration C respectively, and a control circut 35 gives a calibration start command to a calibration device, and zero calibration liquid is supplied from a zero point calibration liquid tank to a density detector which makes a measurement. The output of the detector is converted into linear signals by a signal conversion circuit 31 and converted signals pass through the contact point (c) of the change-over switch 32a and enter an output circuit 33 where they are converted into a density value. At the same time, these signals are memorized in memories 38, 40. Upon completion of a zero point calibration, the control circuit 35 is changed- over to span calibration, and similarly signals at that time are memorized in memories 39, 41. Upon completion of calibration operations, an arithmetic operation circuit 36 reads out these memorized values, caliculates values of density and renews and compensates the constants of an arithmetic operation formula.

Description

[Detailed description of the invention] [Technical field of the invention] ・
TECHNICAL FIELD The present invention relates to a water quality meter, and more particularly to a water quality meter having a function of performing a calibration operation at predetermined intervals and automatically correcting measurement results based on the results.

[Technical background of the invention and its problems]: ・Water quality meters used to measure the water quality of wastewater such as sewage and factory wastewater are heavily contaminated and must be carefully cleaned and cleaned in order to maintain their performance. Short-term calibration is required. ′
・The operation and calibration work will be explained using a concentration meter with an automatic cleaning mechanism, which is one of this type of water quality instruments, as an example. FIG. 1 [al] is an installation example of an optical densitometer detector, and FIG. 1 [81 is a schematic diagram of an optical densitometer (hereinafter referred to as densitometer) detector. It is directly smoked into the sludge liquid (1) of sewage treatment plants, etc. , the concentration meter detector (2) is
Inside the protection tube (3).

It consists of a light source (6) and a light receiving element (7) facing each other with a transparent square measuring tube (8) attached to the tube.

(9) - The piston seal is constantly reciprocating □ to protect the wall of the measuring tube (8) from dirt. At the sub-regular time, the piston seal (9) rises to suck up the sludge liquid into the measuring tube (8), and the amount of light from the light source (6) that passes through this sludge and liquid and is received by the light receiving element (7) is measured. , to find the concentration.

In order to maintain concentration measurement accuracy, after inserting the device into the sludge solution, remove it from time to time to remove dirt on the ground.

After checking the operating state, the detection section (2) is inserted into a container containing a calibration solution to perform calibration work. A transparent calibration solution (pure water, tap water, etc.) is used for zero point calibration, and a standard concentration solution (formazin, kaolin, etc.) or a known concentration solution is used for span calibration. Then, after the calibration was completed, it was inserted into the sludge liquid again.

Since the calibration work is very time-consuming, we have made it possible to perform calibration by injecting the calibration solution into the measurement tube of the concentration meter detector while it is installed.
A concentration meter with a calibration solution supply pipe connected to one part of the fixed tube□1
□ Do 11. However, even with this method, one person intervenes □
There is no change in performing the calibration operation.

Furthermore, it is desired that the water quality meter itself performs automatic branching.

[Purpose of the invention]

The real deal! The object of the present invention is to provide a water quality meter having a function of automatically performing a calibration operation on a predetermined circle, q, and q, and automatically correcting a measurement result based on the result.

[Summary of the Invention]: The present invention includes a water quality detector, a calibration device, a conversion device, and a timer, and based on the predetermined period of the timer, the conversion device switches from normal measurement to calibration operation. A control circuit controls the water quality detector and the calibration device to automatically calibrate the water quality detector.

The output of the water quality detector during the calibration operation and the water quality value calculated from this output are respectively stored in the memory in the converter, and the arithmetic circuit in the converter reads from the memory during normal measurement after the calibration operation is completed. Read each stored value and calculate the water quality value from the water quality detector output using an arithmetic formula using them as constants, and then use the water quality detector output obtained during the next calibration operation and the water quality value calculated from it to write the memory contents. The purpose of the water quality meter is to realize a water quality meter characterized in that a calculation circuit calculates a water quality value from a water quality detector output using a calculation formula using the updated stored value as a constant until the calibration operation is performed again. achieved.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.

Figures 2 to 4 show an embodiment of the water quality meter according to the present invention. Figure 2 is a block diagram showing the overall configuration, Figure 3 is a pipe diagram showing the calibration device, and Figure 4 is a conversion diagram. FIG. 2 is a block diagram showing the configuration of the device.

In the water quality meter according to one embodiment of the present invention, the water quality detector is a concentration meter detector, and as shown in FIG.
), a converter (41), a calibration device (5), and a timer 01.The concentration 1 detector (2) is the same as that shown in FIG.

The calibration device f51 will be explained. In Figure 3, (9) is the piston seal that moves up and down inside the measuring tube (8), point a is the piston seal stop position during calibration work, point 6 is the upper limit position of the piston seal during normal measurement, and point 0 is the piston seal stop position during calibration work. The piston seal is at the lower limit during normal measurement. Calibration liquid outlet (161) provided below point a of measurement tube (8) □ Calibration liquid supply path 0
31 is connected, and the external force from the holder (I□2) is connected to the calibration liquid supply pipe a4.A valve e31 and a pump 0η are connected in series to this calibration liquid supply pipe 041 via a check valve (9). and then branched out at the T-joint (+'81).

One branch pipe is connected in series with valve 09 and a calibration liquid tank (2) for point calibration, and the other branch pipe is connected in series with valve C (11 and a calibration liquid tank (2) for span calibration liquid. 224
3 - Retail connecting two rows. Noro 31 above. ta41.
C! 1, 1231, 0? l.

(Dan, σ9.(2■, (', !11 and 4 constitute the calibration solution supply system.

Furthermore, the calibration liquid supply piping sieve, check valve (2), and valve CI! 3
1, and a valve (c) and an air pump (c) are connected in series to the branched piping. The above (2 in i (24)), 2ω, and the track constitute a calibration liquid discharge means.

In the figure, a dashed dotted line aυ indicates a measurement optical path consisting of a light source and a light receiving element. ' □ Next, the conversion device (41 will be explained. In Fig. 4, C
311 is a signal conversion circuit that outputs □ from the S concentration meter detector (2).
The output signal C30+ is input, and the relationship between the input signal and the output signal is converted to be linearly proportional. (32a), (326
) is a changeover switch, which switches between calibration tc+ and normal measurement (goods) in response to a signal from timer σ. (to) is an output circuit which receives the output of the signal conversion circuit rule and outputs a signal indicating the density value.

Inside and outside are selector switches to switch between automatic and manual operation. If it is automatic, everything will be done automatically, and if it is manual, a human will intervene to perform the operation.

□□□ is a control circuit that controls the movement of the piston seal (9), the stop position, the operation of the calibration device t5+, the arithmetic circuit circle, and the gate (
37a), (37b), etc. The arithmetic circuit (2) is a circuit that receives the output signal from the signal conversion circuit and calculates a concentration value according to a command from the control circuit (g). game t' (37
a) is the output of the signal conversion circuit cA11 during one calibration operation according to the command of the control circuit C35)〉Mo 1 time m <381
; Distribute to <<t.

The gate (37h) memorizes the output of the output circuit G3 during the calibration operation using the finger metal '1 of the control circuit O injection l) circuit 'f4[
), (Distribute to 411. □ ・ □
- ⑼ is an X memory circuit that memorizes the output of the signal conversion circuit (311) during zero point calibration, and (A) is a Yo memory circuit that memorizes the output of the output circuit (G) during zero point calibration. c3I is Nobufue Homare Shoji (31) at the time of span calibration.
It is an xs memory circuit that stores the output of +, (41)
is a memory circuit that outputs the span calibration liquid output circuit i3:s+me.

(44) is an amplifier circuit % (421 is a voice meter that indicates the concentration value, such as an ammeter, a voltmeter, a digital display, etc.).

(431 is a transmission signal, which is an output signal of 4 to 20 mA, etc.) □ Next, an embodiment of the present invention configured as described above.
Hypothesis 8i1' is based on the action of the water quality meter in □. First, the calibration operation and calibration liquid discharge operation of the calibration device will be described with reference to Figure 3. Connect the piston seal (9) to the calibration fluid outlet (16).
) Stop at a higher position a, Mori, close valve a6+, and close valve c! 3) Open the 4-point calibration solution (20) or (22), open any of the 4 sides of the CD, and operate the pump 0η.

is span calibration liquid (chest valve @, T joint (24), check valve circle.

The calibration solution is sent from the calibration solution supply pipe 0 into the calibration solution outlet (from +e+ to the measuring tube tB) via the calibration solution supply path (131).
□Measure the concentration of this calibration solution using an optical sensor and a light receiving element to calibrate the instrument. After the calibration is completed, stop the pump force, close the □ valve (23, valve 01 or Ca*,
Open the valve (25) and operate the air pump (261 to flow air into the calibration liquid supply pipe σa) for a certain period of time. By this air blow, the calibration liquid contained in the pipe line and the measuring tube (8) is discharged. After a predetermined period of time has elapsed, the piston seal (9) is lowered to the upper limit position during normal measurement while air is flowing, and then stopped. After the piston seal (9) stops at point b, stop the air pump (26j) and close the valve (251) to stop the air and complete the calibration liquid discharge operation.After that, the normal measurement state returns.During normal measurement, the piston The seal f91 performs reciprocating motion between point b and point 0.

Next, referring to FIG. 4, an explanation will be given of the automatic calibration operation performed by the converter I. When the switch +(34: is set to i(λ)), the second - timer OI operates, and when the set time comes, the switch (32"a)",'(32'b
) to the calibration TCL side. On the other hand, a calibration start command is given to the control circuit (351 is the calibration device r5) to move the piston seal 19) to point a. □When movement is completed, valve (23+;'(1!I'+open, pump 0η
Move the zero point calibration solution tank i (2*) and add the zero point calibration solution to the densitometer detector (2) to measure the force.

The output from this detector (2) can be determined by the signal conversion circuit T31). □The converted signal passes through the contact tc+ of the switching switch (32a) and becomes the input signal of the output circuit 031. At the same time, the gate (37a) causes X. Stored in memory ■. Further, a signal indicating the concentration value calculated by the output circuit C331 is outputted by a gate (37b). Note memorized on January 41st.

When the above zero point calibration operation is completed, the control circuit t35) closes the valve H of the calibration device (5), opens the 'valve 3D, and moves from the span calibration liquid tank (221) to the calibration liquid number concentration i detector (
2) Perform the feed measurement. Then, get down (:37a,
, , ), , (, 3, 7b,), and the I-code conversion circuit C1! The outputs of the Φ output and output circuits (g) are X, memo 'JC%,! 1t4 and γ,, Memo I
+ (I can remember it in 411.

When this span calibration operation is completed, the circuit 1-c3 sends a command to the calibration device (5) to perform a calibration liquid discharge operation. During this time, the signal between the arithmetic circuits is set to X according to the command of the control circuit 03 clause. The density value is calculated by reading the stored values in memory C38), XIl memory (31F MO memo I month 4G, y, memo January 41). Now, the output of the signal conversion circuit C (II is X, the conversion circuit C33) is y, and the circuit (311 and i'1) at the time of zero point and span calibration is
Let the output of each of ~ be X. .

x8 and y. +yB, then y is X, X.

It is expressed by equation (1). Therefore, the arithmetic circuit (3
) is configured to perform the calculation of equation (1).

Therefore, let T be the setting cycle of timer OQ, and let X be the neutral power of signal conversion circuit Ca1l in the calibration operation at a certain operation time T. 11" 61s output times j72Bf ■ output y.I
, ys□. Further, at an operation time T, which has elapsed by T from 〒,. Signal conversion circuit (31;
The output of 2°, xI12. Assuming that the output of the output circuit C331 is 3(ol', i *y@2, y in equation (1) at time T,1 is Y1$y in equation (1) at time T2 is y!
Then, by substituting the above six values into equation (31), the arithmetic expression of the arithmetic circuit (to) is as follows.

Equations (2) and (3) become as follows.

In this way, the measurement state of the detector is calibrated by flowing the calibration liquid every cycle T set by the timer 0.0). Therefore, each time the calibration result is fed back to the arithmetic circuit (g) according to equation (1) and the constant of the arithmetic equation is updated and corrected, so that the correct sub-constant is maintained. .

In addition, if the changeover switch (341 is switched to manual [FI+), the contents of the memory 1 (31 (1 to (4I)) can be updated by performing a calibration operation at any time regardless of the set cycle of the timer OC.

When the above-mentioned calibration operation is completed, regardless of whether it is automatic or manual, the changeover switch, (32a > , (32b,)
is usually switched to the constant (goods) side. At this time, the concentration meter detector (2) measures the concentration.
), a detection signal is input to the signal conversion circuit 311. If the output of the signal conversion circuit clt+ at this time is Xl, then 1.
xl passes through the contact of the changeover switch (32a) and is manually operated by the calculation circuit (2) according to equation (1), and the concentration value deviation is output. For example, if it is a normal measurement after completing the calibration operation at time T1 mentioned above, the calculation result by the calculation circuit ■ at this time is the output X of the signal conversion circuit c (11), By substituting The calculation result, that is, the density value signal is held.

The concentration value neutral force of the arithmetic circuit (36) during spring measurement is:
The signal is amplified by an amplifier circuit (441) and displayed on four indicators (4), and sent out as a 1. transmission signal (43).

Note that the present invention is not limited to the above-mentioned embodiment □, but can be modified and implemented as follows. .

[1] The above-mentioned embodiments have been explained using an example in which the water quality detector is a densitometer detector. (Ll, V) It can be carried out in exactly the same way in the case of an optical turbidity meter, and it can also be carried out in the case of an optical turbidity meter. 3. Memories are provided for the zero point and for the span, but it is also possible to increase or decrease the number of memories Φ to calibrate only one point (for example, only the zero point). It is also possible to make it more than one point.

[3] Indicator (It is also possible to display using a recorder, printing device, etc. as the 4th function. Especially when printing measured values using a printing device, the values in the memory at the time of 1 calibration can be displayed in different colors. It is easier to see and check later if the information is printed differently.

[4] As shown in Figure 5, the output of the arithmetic circuit (A) is
Memo January 50
o;> Two layers.

2 memos + 1 depending on the cycle and commands from the control circuit C35)
(50) The data accumulated over a certain period of time may be read into the verification circuit (36), and the arithmetic circuit (g) may perform statistical processing such as averaging or calculating phase coefficients. It is possible.

〔Effect of the invention〕

As described in detail above, according to the present invention, a water quality meter is configured to include a water quality detector, a calibration device, a conversion device, and a timer, and the conversion device switches from normal measurement to calibration operation based on the timer setting cycle, and the control circuit The water quality detector and the calibration device are controlled to perform the calibration operation with the detector installed in the liquid to be measured, and the output of the water quality detector during the calibration operation and the water quality value calculated from the output are respectively calculated as above. The arithmetic circuit in the converter reads out the stored values and calculates them from the water quality detector output using an arithmetic formula using them as constants during normal measurement after the end of the lid operation. The water quality value is calculated, and the memory contents are updated using the water quality detector output obtained during the first calibration operation and the water quality value calculated from the water quality value. From then on, the updated stored value is used as a constant until the repeated calibration operation. According to the calculation formula, the calculation circuit calculates the water quality detector: 1ilji, water quality value, 4□. E6, 7□71, the half θ mepan calibration result is sent to the arithmetic circuit every time it is calibrated, and the constant of the arithmetic expression is updated and corrected. , the correct water quality i1+1 can be maintained.In addition, since the correct operation for each furnace cycle is performed in total 1. → with the water quality detector installed, the internal width is reduced compared to conventional equipment. Labor-saving is achieved.Furthermore, if you switch to 1 manual mode, you can calibrate at any time, which is convenient.
be.

[Brief explanation of drawings]

Figure 1 (al is an explanatory diagram showing an example of the installation of an optical concentration meter detector, Figure 1fbl is a cross-sectional view of the optical concentration meter detector,
Figures 4 to 4 show an embodiment of the water quality meter according to the present invention. Figure 2 shows the overall configuration/lock diagram, Figure 3 shows the calibration device, and Figure 4 shows the conversion device. FIG. 5 is a block diagram showing the configuration of the device, and FIG. 5 is a water block diagram showing a modification of the converting device for a water quality meter according to the present invention. 2... Water quality detector 4... Conversion device 5...
Calibration device 6... Light source 7... Light receiving element 8... Measuring tube 9... Piston seal 1o... Timer 30... Detector output signal 31... Signal conversion circuit 32a,
32b... Selector switch 33... Output circuit 34.
...Selector switch 35...Control circuit 36...
・Arithmetic circuit 37a, a'yh-・Kale “38...x0 memory 39・
・1, memory 40...Yo memory 41・
...y, memory 42...indicator 43...
・Transmission signal 44...Amplification circuit 5o...2
Memory Agent Patent Attorney Mr. Inoue Figure 1 Figure 2

Claims (1)

[Claims] (1) Water quality detector, calibration device, conversion device, and tie.
1. (Based on the set period of the timer, the quasi-equipment switches from normal measurement to calibration operation.) The water quality detector and the calibration device are controlled by the control circuit in the conversion equipment, and the water quality detector is activated. Automatic calibration 1. Calculate the water quality values calculated from the detector output during the calibration operation and the output of During the measurement operation, the arithmetic circuit in the conversion device reads out the respective memorized values from the parallel newt, sets them as constants, and calculates the water quality value from the water, quality detector, and output using the arithmetic formula. Then, during the next calibration operation,
The memo, contents, and contents are all updated using the obtained water quality detector output and the water quality value calculated from it, and from then on, the arithmetic circuit detects the water quality by using the updated memorized value as a constant until the calibration operation is performed again. A water quality meter that uses a tube to calculate water quality values from the device output. , . '(2) The converting device has a memory for storing the output of the arithmetic circuit, and the arithmetic circuit has a function of reading data sequentially stored in the memory at appropriate intervals and performing statistical processing. □Claim 1
Water quality meter as described in section. ,′,.