CN211927774U - Novel portable multifunctional water quality monitoring system - Google Patents
Novel portable multifunctional water quality monitoring system Download PDFInfo
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- CN211927774U CN211927774U CN202020360173.5U CN202020360173U CN211927774U CN 211927774 U CN211927774 U CN 211927774U CN 202020360173 U CN202020360173 U CN 202020360173U CN 211927774 U CN211927774 U CN 211927774U
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Abstract
The utility model discloses a novel portable multifunctional water quality monitoring system, which comprises a control module with MCU, a power supply module electrically connected with the control module, an AC source module electrically connected with the control module and used for providing AC power, a test electrode detection module electrically connected with the control module and used for detecting a test electrode, a reference electrode detection module electrically connected with the control module and used for detecting a reference electrode, a temperature detection module electrically connected with the control module and used for detecting water temperature, and a buzzer warning module electrically connected with the temperature detection module; the alternating current programmable voltage power supply is the guarantee of high reliability of the system, avoids electrode polarization, and has extremely high reference value and popularization significance; the detection electrode and the reference electrode are separately and independently used for detection, so that accurate ion concentration measurement is realized; the portable mobile test device is particularly suitable for portable mobile test environments, and lays a foundation for popularization in remote areas.
Description
Technical Field
The utility model relates to a water quality monitoring technology field especially relates to a novel portable multi-functional water quality monitoring system.
Background
With the development of social economy, scientific progress and improvement of the living standard of people, the requirements of people on the water quality of drinking water are continuously improved, and the water quality standard of the drinking water is correspondingly continuously developed and improved. Particularly, the two most basic indexes of pH value and water hardness are closely related to the health of people, and the establishment of the water quality standard of the drinking water is related to various factors such as living habits, cultures, economic conditions, scientific and technical development level, water resources, water quality current situations and the like of people.
The high-tech precise water quality monitoring has high cost and great popularization difficulty, some monitoring devices in the market have poor reliability and short service life, most of the monitoring devices adopt common electrodes to realize basic detection functions, and the effect of the monitoring devices is widely questioned.
People hope that a portable water quality detector with high reliability and low cost appears.
The information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information constitutes prior art already known to a person skilled in the art.
Based on the reasons, the applicant provides a novel portable multifunctional water quality monitoring system, and aims to solve the problems.
SUMMERY OF THE UTILITY MODEL
In order to meet the requirements, the utility model aims to provide a novel portable multifunctional water quality monitoring system.
In order to achieve the above purpose, the utility model adopts the following technical scheme:
a novel portable multifunctional water quality monitoring system comprises a control module with an MCU, a power supply module electrically connected with the control module, an alternating current source module electrically connected with the control module and used for providing an alternating current power supply, a test electrode detection module electrically connected with the control module and used for detecting a test electrode, a reference electrode detection module electrically connected with the control module and used for detecting a reference electrode, a temperature detection module electrically connected with the control module and used for detecting water temperature, and a buzzer warning module electrically connected with the temperature detection module;
the test electrode test module comprises a voltage follower for detecting a test electrode, and is connected with the negative electrode of the test electrode and the negative electrode of the reference electrode;
the alternating current source module comprises a test electrode and a reference electrode, wherein the test electrode is used for generating a potential difference relative to the reference electrode, and the reference electrode is used for providing a constant reference potential.
In one possible embodiment, the reference electrode detection module includes a current detection circuit for detecting the reference electrode, the current detection circuit including an instrumentation amplifier to which the reference electrode is connected, a differential amplifier connected to the instrumentation amplifier, and a differential amplifier connected to the differential amplifier.
In one possible embodiment, the first pin of the instrumentation amplifier is connected to the positive electrode of the reference electrode, the fourth pin of the instrumentation amplifier is connected to the negative electrode of the reference electrode, and the second pin and the third pin of the instrumentation amplifier are connected to the gain selection resistor.
In one possible embodiment, the fourth pin and the tenth pin of the differential amplifier are connected with the seventh pin of the instrumentation amplifier, the third pin of the differential amplifier is connected with the moving end of the first single-pole double-throw switch, and the two fixed ends of the single-pole double-throw switch are respectively arranged on the second pin and the fourth pin of the differential amplifier;
an eleventh pin of the differential amplifier is connected with a movable end of a second single-pole double-throw switch, and two fixed ends of the second single-pole double-throw switch are respectively arranged on a tenth pin and a twelfth pin of the differential amplifier;
the third pin and the eleventh pin of the differential amplifier are respectively connected with the second pin and the third pin of the differential amplifier, the second pin and the third pin of the differential amplifier are connected with the output end of the differential amplifier through a buffer, and the output end of the differential amplifier is connected with a voltage output end which is always positive voltage.
In one possible embodiment, the ac source module includes a programmable ac voltage source circuit, and the programmable ac voltage source circuit includes a CMOS analog multiplexer connected to the positive electrode of the test electrode and the positive electrode of the reference electrode, an operational amplifier connected to the CMOS analog multiplexer, a hardware switch connected to an input terminal of the operational amplifier, and an operational amplifier disposed between the hardware switch and the voltage input terminal.
In one possible embodiment, the test electrode detection module comprises an alternating current loop forming circuit, the alternating current loop forming circuit comprises a CMOS analog multiplexer connected with the negative electrode of the test electrode and the negative electrode of the reference electrode, a differential amplifier connected with the CMOS analog multiplexer, and a differential amplifier connected with the differential amplifier;
resistors are arranged among the negative electrode of the test electrode, the negative electrode of the reference electrode and the CMOS analog multiplexer, a node between the negative electrode of the test electrode and the negative electrode of the reference electrode is connected with an operational amplifier, and the output end of the operational amplifier is connected with the differential amplifier and the CMOS analog multiplexer.
In one possible embodiment, the power source of the power supply module is a dry battery or a lithium battery, and the power supply module includes a power supply circuit electrically connected with the dry battery or the lithium battery.
In one possible embodiment, the control module comprises an MCU, an LCD display connected to the MCU and used for displaying water quality test data, a peripheral circuit, and a hardware bias circuit.
In one possible embodiment, the temperature detection module includes a liquid temperature detection circuit for detecting water temperature and for compensation and correction.
In one possible embodiment, the buzzer module comprises a buzzer circuit, the buzzer circuit comprises a buzzer, a resistor connected in parallel with the buzzer, a MOS transistor connected in series with the buzzer, and an input end for driving the MOS transistor to be turned on.
Compared with the prior art, the beneficial effects of the utility model reside in that: the portable multifunctional water quality detection system of the scheme is powered by the dry battery or the lithium battery, and the portable characteristic is realized. The programmable alternating voltage is adopted to supply power to the electrode, so that the performance reduction of the electrode due to long-time polarization can be prevented, the frequency and the amplitude of the alternating voltage can be changed, and the derivation and the practicability are very strong; by using a two-electrode test, i.e., testing motor a and reference electrode B, the reference electrode functions to provide a constant reference potential independent of the solution in which the electrodes are immersed. The effect of the measuring electrode is to create a potential difference with respect to the reference electrode which is proportional to the pH of the solution. The pH electrode has a very large output resistance, and in order to achieve accurate pH measurement, a low bias current amplifier is applied as a buffer. After passing through the low leakage buffer stage, the signal is provided to the gain and low pass filter stages to achieve higher resolution. The signal finally enters the ADC.
The system adopts the detection electrode and the reference electrode to separately and independently detect, thereby realizing accurate ion concentration measurement; in addition, the system is added with a temperature correction compensation function, so that the test is accurate, the equipment cost is moderate, the portable mobile test environment is particularly suitable, and a foundation is laid for popularization in remote areas.
The invention is further described with reference to the accompanying drawings and specific embodiments.
Drawings
FIG. 1 is a schematic diagram of a frame of a specific embodiment of the novel portable multifunctional water quality monitoring system of the present invention;
FIG. 2 is a schematic diagram of a current sense circuit for sensing a reference electrode of the reference electrode sensing module of the system of FIG. 1;
FIG. 3 is a schematic diagram of a programmable AC voltage source circuit of the AC source module of the system of FIG. 1;
FIG. 4 is a schematic diagram of an AC loop forming circuit of the test electrode detection module of the system of FIG. 1;
FIG. 5 is a schematic diagram of a power supply circuit of the power supply module of the system of FIG. 1;
FIG. 6 is a schematic diagram of an LCD display circuit of the control module of the system of FIG. 1;
FIG. 7 is a schematic diagram of a hardware bias circuit of the control module of the system of FIG. 1;
FIG. 8 is a schematic diagram of the MCU and peripheral circuitry of the control module of the system of FIG. 1;
FIG. 9 is a schematic diagram of a liquid temperature sensing circuit of the temperature sensing module of the system of FIG. 1;
figure 10 is a schematic diagram of the buzzer circuit of the buzzer warning module of the system of figure 1.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those skilled in the art without creative efforts belong to the protection scope of the present invention.
In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and to simplify the description, but do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the present invention.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically limited otherwise.
In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "secured" are to be construed broadly and can, for example, be connected or detachably connected or integrated; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.
In the present disclosure, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may comprise direct contact between the first and second features, or may comprise contact between the first and second features not directly. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.
In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above should not be understood to necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples described in this specification can be combined and combined by those skilled in the art.
As shown in fig. 1-10, the novel portable multifunctional water quality monitoring system proposed by the present invention comprises a control module 100 having an MCU, a power supply module 200 electrically connected to the control module 100, an ac source module 300 electrically connected to the control module 100 and used for providing an ac power source, a test electrode detection module 400 electrically connected to the control module 100 and used for detecting a test electrode, a reference electrode detection module 500 electrically connected to the control module 100 and used for detecting a reference electrode, a temperature detection module 600 electrically connected to the control module 100 and used for detecting water temperature, and a buzzer warning module 700 electrically connected to the temperature detection module 600;
the test electrode detection module 400 includes a voltage follower for detecting a test electrode, and the test electrode detection module 400 is connected with a negative electrode of the test electrode and a negative electrode of a reference electrode;
the ac source module 300 includes a test electrode for generating a potential difference relative to a reference electrode for providing a constant reference potential.
In the embodiment shown in fig. 2, the reference electrode detection module comprises a current detection circuit for detecting the reference electrode, the current detection circuit comprises an instrumentation amplifier U10 connected with the reference electrode (B1+, B1-), a differential amplifier ADF1636 connected with the instrumentation amplifier U10, and a differential amplifier AD8271 connected with the differential amplifier ADF 1636.
The technical scheme is that a first pin of the instrumentation amplifier U10 is connected with a positive electrode B1+ of a reference electrode, a fourth pin of the instrumentation amplifier U10 is connected with a negative electrode B1-of the reference electrode, and a second pin and a third pin of the instrumentation amplifier U10 are connected with a gain selection resistor R8.
A fourth pin and a tenth pin of the differential amplifier ADF1636 are connected with a seventh pin of the instrumentation amplifier U10, a third pin of the differential amplifier ADF1636 is connected with a moving end of a first single-pole double-throw switch, and two non-moving ends of the single-pole double-throw switch are respectively disposed on a second pin and a fourth pin of the differential amplifier ADF 1636;
an eleventh pin of the differential amplifier ADF1636 is connected with a moving end of a second single-pole double-throw switch, and two fixed ends of the second single-pole double-throw switch are respectively arranged on a tenth pin and a twelfth pin of the differential amplifier ADF 1636;
the third pin and the eleventh pin of the differential amplifier ADF1636 are respectively connected with the second pin and the third pin of the differential amplifier AD8271, the second pin and the third pin of the differential amplifier AD8271 are connected with the output end of the differential amplifier AD8271 through a buffer, and the output end of the differential amplifier AD8271 is connected with a voltage output end BV-check which is always positive in voltage.
Specifically, when the system starts to measure, ions between the electrodes B move to form alternating voltage at two ends of the electrodes, the alternating voltage is amplified by U10 and then is input to the rear end, and high-precision amplification is realized for small signals; the illustrated R8 is a gain selection resistor, since the output of the U10 is ac, the U11 is a differential amplifier, the MCU can realize positive amplification of negative input by setting the MCU _ IN1, the MCU _ IN2, and the MCU _ EN11, thereby realizing a rectification function and ensuring that the output analog voltage BV _ check is always positive; thus, the voltage detection at the two ends of the electrode B is realized.
In the embodiment shown in fig. 3, the ac source module includes a programmable ac voltage source circuit, and the programmable ac voltage source circuit includes a CMOS analog multiplexer ADG704 connected with a test electrode anode a1+ and a reference electrode anode B1+, an operational amplifier U7 connected to the CMOS analog multiplexer ADG704, a hardware switch U6 connected to an input terminal of the operational amplifier U7, and an operational amplifier U5 disposed between the hardware switch U6 and a voltage input terminal.
Specifically, the circuit shown in FIG. 3 is intended to provide AC power to the electrodes, with U5 outputting a voltage of-2V 5 after reverse amplification; the U6 hardware switch selects and outputs S1A or S1B through connecting the pin MCU-S of the MCU, and realizes that 2V5 or +2V5 is output at the D1 end of U6.
U7 realizes amplification and adjustment through adjusting the resistance of R1, R5, U9 is multichannel multiplexing switch, MCU-A0, MCU-A1, MCU-EN carry out channel selection, electrode A and electrode B are connected in a time-sharing manner, U8 realizes that the positive pole of output voltage follows to ensure that input and output are consistent, the whole U5, U6, U7, U8, U9 realize the voltage adjustable alternating voltage source, provide programmable alternating voltage for the electrode, the frequency is adjustable, and the amplitude is adjustable.
In the embodiment shown in fig. 4, the test electrode detection module comprises an ac loop formation circuit comprising a CMOS analog multiplexer ADG704 connected to a test electrode negative a 1-and a reference electrode negative B1-, a differential amplifier ADF1636 connected to the CMOS analog multiplexer ADG704, and a differential amplifier AD8271 connected to the differential amplifier ADF 1636;
resistors R9 are arranged between the test electrode cathode A1-and the reference electrode cathode B1-and the CMOS analog multiplexer ADG704, a node B1-between the test electrode cathode A1-and the reference electrode cathode is connected with an operational amplifier U13, and the output end of the operational amplifier U13 is connected with a differential amplifier U16 and the CMOS analog multiplexer U15.
In particular, the circuit shown in fig. 4 is connected to fig. 2, and is intended to form an alternating current circuit, while enabling voltage detection across electrode a;
the voltage follower is composed of U13 and U15, and the MCU controls MCU-B0, MCU-B1 and MCU-EN15 to realize the cut-in from the electrode A or the electrode B;
because the output of the U13 is alternating current, the U16 is a differential amplifier, and the MCU can realize time-sharing switching-IN of an A electrode and a B electrode and positive amplification of negative input by arranging the MCU _ IN3, the MCU _ IN4 and the MCU _ EN16 on one hand, so that a rectification function is realized, and the output analog voltage AV _ check is always positive.
In a preferred embodiment, the power source of the power supply module is a dry battery or a lithium battery, so as to realize the portability of the system.
In the embodiment shown in fig. 5, the power supply module includes a power supply circuit electrically connected to a dry battery or a lithium battery. The power supply circuit is powered by a lithium battery, a voltage division circuit consisting of R29, R30 and R31 is connected with the MCU VBAT-CK for voltage detection, and low-voltage reminding and alarming are performed;
the U4, the D2, the L1, the R6, the R10 and the C8 form a booster circuit, and the battery voltage is boosted to 5V to supply power to a load; the U2 voltage regulator tube provides stable DC5V voltage for the MCU; u3 is a reference voltage source and provides a stable reference voltage 2V5 for the system, and is used as a reference voltage and other references in the MCU.
In the embodiments shown in fig. 6, 7 and 8, the control module includes an MCU, an LCD display connected to the MCU and used for displaying water quality test data, a peripheral circuit and a hardware bias circuit.
Specifically, the MCU is internally provided with an LCD drive circuit, and the data of the water quality test can be displayed by an LCD display, so that a user can observe and judge the current water quality condition conveniently.
In the embodiment shown in fig. 9, the temperature detection module includes a liquid temperature detection circuit for detecting water temperature and for compensation and correction.
The water quality with the same ion concentration has different conductivity under different temperature environments, and the liquid temperature detection circuit is used for detecting water temperature for compensation and correction; when the ion concentration of the water is too high or the pH value of the water exceeds the range, the buzzer is used for alarming.
In the embodiment shown in fig. 10, the buzzer module includes a buzzer circuit, and the buzzer circuit includes a buzzer, a resistor connected in parallel with the buzzer, a MOS transistor connected in series with the buzzer, and an input terminal for driving the MOS transistor to be turned on.
In conclusion, the alternating current programmable voltage power supply adopted in the design system is the guarantee of high reliability of the system, electrode polarization is avoided, and the design system has extremely high reference value and popularization significance;
secondly, the system adopts a detection electrode and a reference electrode to separately and independently detect, so that accurate ion concentration measurement is realized;
in addition, the system is added with a temperature correction compensation function, so that the test is accurate, the equipment cost is moderate, the portable mobile test environment is particularly suitable, and a foundation is laid for popularization in remote areas.
Various other modifications and changes can be made by those skilled in the art based on the above-described technical solutions and concepts, and all such modifications and changes should fall within the protection scope of the present invention.
Claims (10)
1. A novel portable multifunctional water quality monitoring system is characterized by comprising a control module with an MCU, a power supply module electrically connected with the control module, an alternating current source module electrically connected with the control module and used for providing an alternating current power supply, a test electrode detection module electrically connected with the control module and used for detecting a test electrode, a reference electrode detection module electrically connected with the control module and used for detecting a reference electrode, a temperature detection module electrically connected with the control module and used for detecting water temperature, and a buzzer warning module electrically connected with the temperature detection module;
the test electrode test module comprises a voltage follower for detecting a test electrode, and is connected with the negative electrode of the test electrode and the negative electrode of the reference electrode;
the alternating current source module comprises a test electrode and a reference electrode, wherein the test electrode is used for generating a potential difference relative to the reference electrode, and the reference electrode is used for providing a constant reference potential.
2. The novel portable multifunctional water quality monitoring system according to claim 1, wherein the reference electrode detection module comprises a current detection circuit for detecting the reference electrode, and the current detection circuit comprises an instrumentation amplifier connected with the reference electrode, a differential amplifier connected with the instrumentation amplifier, and a differential amplifier connected with the differential amplifier.
3. The novel portable multifunctional water quality monitoring system according to claim 2, wherein a first pin of the instrumentation amplifier is connected with a positive electrode of a reference electrode, a fourth pin of the instrumentation amplifier is connected with a negative electrode of the reference electrode, and a second pin and a third pin of the instrumentation amplifier are connected with a gain selection resistor.
4. The novel portable multifunctional water quality monitoring system according to claim 3, wherein a fourth pin and a tenth pin of the differential amplifier are connected with a seventh pin of the instrumentation amplifier, a third pin of the differential amplifier is connected with a movable end of a first single-pole double-throw switch, and two immovable ends of the single-pole double-throw switch are respectively arranged on a second pin and a fourth pin of the differential amplifier;
an eleventh pin of the differential amplifier is connected with a movable end of a second single-pole double-throw switch, and two fixed ends of the second single-pole double-throw switch are respectively arranged on a tenth pin and a twelfth pin of the differential amplifier;
the third pin and the eleventh pin of the differential amplifier are respectively connected with the second pin and the third pin of the differential amplifier, the second pin and the third pin of the differential amplifier are connected with the output end of the differential amplifier through a buffer, and the output end of the differential amplifier is connected with a voltage output end which is always positive voltage.
5. The system of claim 1, wherein the AC power supply module comprises a programmable AC power supply circuit, the programmable AC power supply circuit comprises a CMOS analog multiplexer connected with a test electrode anode and a reference electrode anode, an operational amplifier connected with the CMOS analog multiplexer, a hardware switch connected with an input end of the operational amplifier, and an operational amplifier arranged between the hardware switch and a voltage input end.
6. The novel portable multifunctional water quality monitoring system according to claim 1, wherein the test electrode detection module comprises an alternating current loop forming circuit, the alternating current loop forming circuit comprises a CMOS analog multiplexer connected with a negative electrode of the test electrode and a negative electrode of the reference electrode, a differential amplifier connected with the CMOS analog multiplexer, and a differential amplifier connected with the differential amplifier;
resistors are arranged among the negative electrode of the test electrode, the negative electrode of the reference electrode and the CMOS analog multiplexer, a node between the negative electrode of the test electrode and the negative electrode of the reference electrode is connected with an operational amplifier, and the output end of the operational amplifier is connected with the differential amplifier and the CMOS analog multiplexer.
7. The system of claim 1, wherein the power supply module is a dry battery or a lithium battery, and the power supply module comprises a power supply circuit electrically connected to the dry battery or the lithium battery.
8. The system of claim 1, wherein the control module comprises an MCU, an LCD display connected with the MCU and used for displaying water quality test data, a peripheral circuit and a hardware bias circuit.
9. The system of claim 1, wherein the temperature detection module comprises a liquid temperature detection circuit for detecting water temperature and for compensation and correction.
10. The novel portable multifunctional water quality monitoring system according to claim 1, wherein the buzzer module comprises a buzzer circuit, the buzzer circuit comprises a buzzer, a resistor connected in parallel with the buzzer, a MOS (metal oxide semiconductor) tube connected in series with the buzzer, and an input end for driving the MOS to be conducted.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202020360173.5U CN211927774U (en) | 2020-03-19 | 2020-03-19 | Novel portable multifunctional water quality monitoring system |
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| CN202020360173.5U CN211927774U (en) | 2020-03-19 | 2020-03-19 | Novel portable multifunctional water quality monitoring system |
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| CN211927774U true CN211927774U (en) | 2020-11-13 |
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