CN203672408U - Water quality detecting system - Google Patents

Abstract

The utility model discloses a water quality detecting system comprising a single chip microcomputer and a keyboard. The water quality detecting system is characterized in that the single chip microcomputer is connected with the keyboard, a temperature sensor, a power supply, a LCD display, a GSM module, a network interface card module, a serial port module, an AD converting module 2, and an AD converting module 1, that the AD converting module 2 is connected with a dissolved oxygen sensor and a reserved expansion port, and that the AD converting module 1 is connected with a pH sensor and a conductivity sensor.

Description

Water quality detection system

Technical field

The utility model relates to water quality detection system, belongs to water quality inspection technique field.

Background technology

Water is Source of life, and the survival and development of all living things all be unable to do without water.Society, water source crisis has become a global problem.Agricultural and commercial production can have water, and the fresh water consumption in agricultural production has accounted for the mankind and consumed 60%-80% of fresh water total amount, industrially also just can normally produce with enough water.In addition, water also plays very important effect on Shipping.It is the prerequisite of water conservation that water quality is detected, and according to testing result, water resource is protected and processing is most scientific rational method.

By the analysis to different times water quality detection parameter, grasp the trend that water quality changes.The data of water quality detection not only provide scientific basis for the emergency processing that the management of all kinds of pollution source, water pollute accident, and strengthen the protection of water environment that Data support is provided for government formulate development plan, for environmental administration.Therefore water quality detection is significant for strengthening water environment protection and control and solving China's water Pollution Crisis.

Summary of the invention

The utility model is for the proposition of above problem, and development water quality detection system.

Water quality detection system, comprises single-chip microcomputer and keyboard; Single-chip microcomputer connects keyboard, single-chip microcomputer connects temperature sensor, single-chip microcomputer connects power supply, single-chip microcomputer connects LCD and shows, single-chip microcomputer connects gsm module, single-chip microcomputer connection network card module, and single-chip microcomputer connects serial port module, single-chip microcomputer connects AD modular converter two, and AD modular converter two connects dissolved oxygen sensor and reserved expansion mouthful; Single-chip microcomputer connects AD modular converter one, and AD modular converter one connects pH sensor and conductivity sensor; Single-chip microcomputer connects temperature sensor; Gsm module arrives terminal by wireless network communication signal, and network interface card module is connected with terminal wireless by far-end Entrust Server.

Terminal comprises notebook computer and smart mobile phone.

The utility model principle and beneficial effect:

(1) in centralized knowledge after the state of development of domestic and international water quality inspection technique, provide the General layout Plan of conventional parameter water quality detection system.

(2) system is taking STC89C52 single-chip microcomputer as acp chip, be mainly because STC89C52 download more convenient, low price, and easily having bought on market.

(3) in order to realize water temperature, pH value, dissolved oxygen concentration, the data acquisition of conductivity quadrinomial parameter and demonstration, designed sensor interface circuitry and display circuit.

(4) make conventional parameter water quality and count detection system model machine.In system debug, except temperature sensor is cheap, easily buy, because the price of other three sensors is slightly expensive, Sensor section is replaced with potentiometer, after sensor is connected above, just can measure exactly four item numbers certificates and show in real time.

(5) gsm module arrives terminal by wireless network communication signal, and network interface card module is connected with terminal wireless by far-end Entrust Server.Notebook computer and smart mobile phone.Can accept the signal data gathering.

Brief description of the drawings

Fig. 1 is the utility model circuit structure sketch.

Fig. 2 the utility model conductivity sensor circuit.

The circuit of Fig. 3 the utility model pH sensor.

Fig. 4 the utility model circuit construction of electric power sketch.

Embodiment

As shown in Figure 1: water quality detection system, comprises single-chip microcomputer and keyboard; Single-chip microcomputer connects keyboard, single-chip microcomputer connects temperature sensor, single-chip microcomputer connects power supply, single-chip microcomputer connects LCD and shows, single-chip microcomputer connects gsm module, single-chip microcomputer connection network card module, and single-chip microcomputer connects serial port module, single-chip microcomputer connects AD modular converter two, and AD modular converter two connects dissolved oxygen sensor and reserved expansion mouthful; Single-chip microcomputer connects AD modular converter one, and AD modular converter one connects pH sensor and conductivity sensor; Single-chip microcomputer connects temperature sensor; Gsm module arrives terminal by wireless network communication signal, and network interface card module is connected with terminal wireless by far-end Entrust Server.

Terminal comprises notebook computer and smart mobile phone.

Temperature sensor is the very important part of native system.On market, temperature sensor of a great variety.But by DALLAS(Dallas) company produce DS18B20 in numerous temperature sensors, show outstanding.Its price is low, and measuring accuracy is high, convenient application, and volume is little, and antijamming capability is strong, and stability aspect also finds no fault with.As long as and it is connected on an I/O mouth of single-chip microcomputer and just can works.55 DEG C to+125 DEG C of the scope Shi – of detected temperatures.What use is unibus data communication.Precision is 0.5 degree Celsius, soil.Its maximal duty cycle is 750 milliseconds.Inner lasered ROM and the product ID that also has 64, conveniently carries out multimachine and articulates.There is various packing forms, can adapt to different hardware systems.Adopt the mode of one-wire interface, only need a line just can realize the both-way communication of microprocessor and DS18B20.Multiple DS18B20 can be connected in parallel on three lines, but at most can only be in parallel 8, if quantity is too many, may cause the voltage of power supply too low.Chip the inside is provided with temperature detection and two parts of numerical data output, and interference resistance is strong.A work period is made up of temperature detection and these two parts of data processing.It has three kinds of memory resources: RAM data are temporary, ROM ROM (read-only memory), and EEPROM nonvolatile memory.

As shown in Figure 2: conductivity sensor comprises that conductivity signal Acquisition Circuit is by conductance cell, square-wave pulse circuit, semiperiod and later half cycle equal and opposite in direction before the signal U0 sending due to positive negative pulse stuffing, opposite direction, therefore, electrode polarization error is slackened greatly, adopts the method for the detection conductivity of this dipulse can simplify hardware circuit.

Dissolved oxygen sensor adopts DO-98P type dissolved oxygen sensor, and it has higher stability and reliability, can in rugged environment, use, safeguard also less, be applicable to municipal effluent, Industrial Wastewater Treatment, the dissolved oxygen DO METHOD FOR CONTINUOUS DETERMINATION in aquaculture and environment measuring field.Its important technological parameters is as follows:

(1) measurement range: 0-20mg/L

(2) measuring principle: current type sensor (being polarogram formula electrode)

(3) cable line length: 5m (double shield)

(4) response time: 3min (90%, 20 DEG C)

(5) polarization time: 60min

(6) measuring error: < ± 0.1mg/L

(7) output current: 20-25nA/0.1mg/L note: maximum current 3.5uA

(8) tested water quality temperature: 0-60 DEG C

The output signal of DO-98P type dissolved oxygen sensor is very faint current signal (maximum current 3.5uA), therefore, the output signal of sensor be amplified, and becomes voltage signal and sends into A/D converter.About the signal conversion of dissolved oxygen DO, its peripheral circuit is identical with the principle of signal conversion of the pH value that will mention below, and its peripheral circuit is also similar, and just enlargement factor wherein can variant, in side circuit, pass through adjusting slide rheostat realization wherein.

The circuit of pH sensor is as shown in Figure 3: it is direct potentiometric method that pH measures what adopt, also claims ion-selective electrode method, is to utilize membrane electrode being expressed as electrode potential value by the concentration of measured ion, determines the method for ion concentration by potential electrode current potential.Its ultimate principle is that indicator electrode and contrast electrode are inserted in solution to be measured, thus composition primary element.Contrast electrode is the known and constant electrode of electrode potential, indicator electrode current potential and treat to obey Nernst equation between the concentration of measured ion, the primary element of being purchased is connected in to measuring equipment, can obtains the current potential of indicator electrode, just can determine the concentration for the treatment of measured ion by Nernst equation.After pH is become sending, what obtain is the DC current of 4-20mA, and single-chip microcomputer is only accepted digital signal, so current signal will be amplified, becomes voltage signal to send into A/D converter, sends into single-chip microcomputer after simulating signal is become to digital signal again.The output current of pH electrode is transformed into voltage signal, use operational amplifier CA3140 to amplify, because the voltage signal Uph after amplifying is a reverse signal, therefore, by the negative circuit being formed by operational amplifier uA741, output signal U ph2 is again anti-phase, and the signal Uph2 obtaining has reacted the situation of change of pH value on electrode.

LCD shows the demonstration that adopts LCD1602 liquid crystal display to realize data.

Serial port module adopts RS232 serial ports to complete program to enter from computer burning the task of single-chip microcomputer.

Single-chip microcomputer must could normally be worked under stable Power Supplies Condition.So need to provide a stable power supply to single-chip microcomputer, for convenient and practical, selecting provides a stable 5V power supply with computer USB interface.On material object, a USB interface of welding, is then connected single-chip microcomputer with the data line of USB plug with two ends with computer, makes microcontroller power supply stable.Power circuit diagram is as shown in Figure 4: VCC is positive source, and GND is power cathode.S1 is power switch.

Gsm module adopts the Mc39i of Siemens.

Network interface card module adopts BL-RT5370-4A.Notebook computer and smart mobile phone.Can accept the signal data gathering.

The above; it is only preferably embodiment of the utility model; but protection domain of the present utility model is not limited to this; any be familiar with those skilled in the art the utility model disclose technical scope in; be equal to replacement or changed according to the technical solution of the utility model and inventive concept thereof, within all should being encompassed in protection domain of the present utility model.

Claims (2)

1. water quality detection system, comprise single-chip microcomputer and keyboard, it is characterized in that: single-chip microcomputer connects keyboard, single-chip microcomputer connects temperature sensor, and single-chip microcomputer connects power supply, single-chip microcomputer connects LCD and shows, single-chip microcomputer connects gsm module, single-chip microcomputer connection network card module, and single-chip microcomputer connects serial port module, single-chip microcomputer connects AD modular converter two, and AD modular converter two connects dissolved oxygen sensor and reserved expansion mouthful; Single-chip microcomputer connects AD modular converter one, and AD modular converter one connects pH sensor and conductivity sensor; Single-chip microcomputer connects temperature sensor; Gsm module arrives terminal by wireless network communication signal, and network interface card module is connected with terminal wireless by far-end Entrust Server.

2. water quality detection system according to claim 1, is characterized in that: terminal comprises notebook computer and smart mobile phone.

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