CN210863868U - A contact and non-contact sensor - Google Patents

Abstract

The utility model relates to a high-voltage electroscope technical field especially relates to an adopt contact and non-contact sensor. One adopts a contact type and a non-contact type sensor, one end of a contact type metal probe is inserted and connected in a flat plate capacitance type electric field sensor, and the upper end and the lower end of the electric field sensor are respectively connected with a non-contact type lead; the contact lead is connected with the electroscope ground, and the contact probe is connected with the contact lead and the electroscope ground. The utility model discloses the sensor has simple structure, and convenient operation's characteristics can judge according to alarm signal's frequency whether current alarm type is contact warning or non-contact warning, judge the distance of electroscope and equipment of waiting to test far and near according to alarm signal's different frequencies. The guardian can know the electricity testing result in real time, reliability and reliability of the electricity testing result are greatly improved, safety of electricity testing maintenance personnel is improved, correctness of the electricity testing result is improved, false alarm rate is reduced, and whether the equipment to be tested is electrified or not is effectively detected.

Description

A contact and non-contact sensor

technical field

The utility model relates to the technical field of high-voltage electroscope electroscope, in particular to a contact type and non-contact type sensor.

Background technique

The high-voltage electroscope is a kind of power equipment used for high-voltage power maintenance, which is used to judge whether the equipment to be repaired is live. High-voltage electroscopes are divided into contact and non-contact electroscopes. Among them, contact electroscopes are most widely used by directly contacting the equipment to be tested and using the principle of space stray capacitance voltage division. The non-contact electroscope judges whether the device under test is charged by collecting the electric field intensity in space. Since the technology is not mature enough, it is still in the research stage.

During the use of the contact electroscope, due to the different distribution of equipotential lines across the contact probe of the contact electroscope, there are false alarm areas and refusal alarm areas during the operation of the contact type high voltage electroscope. In the false alarm area and the refusal alarm area The test results will be wrong. The non-contact electroscope is prone to false alarms because the collected electric field strength is easily disturbed by the surrounding charged equipment.

Therefore, the high-voltage electroscope in the prior art has shortcomings such as false alarm and refusal to alarm, and refusal to alarm can easily lead to misjudgment by maintenance personnel and cause personal safety accidents, while false alarm will delay precious maintenance time and bring harm to the country and the people. Huge property damage.

SUMMARY OF THE INVENTION

Aiming at the problems existing in the above-mentioned prior art, the present invention provides a contact-type and non-contact-type sensor, the purpose of which is to provide a sensor with a simple structure and convenient operation, and can solve the problems existing in the above-mentioned prior art. The problem of false alarm and refusal to alarm can be verified by non-contact and contact electricity testing in turn in a high-voltage environment to verify whether the object has high-voltage electricity. As a result, the safety, reliability and accuracy of the electrical inspection are greatly improved, and the occurrence of false alarms and refusal to alarm is reduced.

In order to realize the above-mentioned purpose of the utility model, the utility model is realized through the following technical solutions:

A contact type and non-contact type sensor are used. One end of the contact type metal probe is inserted and connected to the flat capacitive electric field sensor, and the upper and lower ends of the electric field sensor are respectively connected with non-contact type wires; the contact type wires are connected with the electroscope ground. The contact probe connects the contact wire and the electroscope ground.

The flat capacitive electric field sensor is annular, with an annular space in the middle. The annular space is fixedly connected with the contact metal probe through fixing bolts, and the contact probe is connected to the contact wire and the output voltage of the electroscope to provide detection for the contact sensor. Signal; the induced voltage of the flat capacitive electric field sensor provides detection signals for the non-contact sensor through the non-contact wires connected to the upper and lower ends of the flat capacitive electric field sensor.

The contact metal probe is combined with a flat capacitive electric field sensor, wherein the two sensors work independently, the contact probe contacts a charged object, and the stray capacitance between the contact metal probe and the electroscope ground is divided into a voltage; the flat capacitive electric field The induced voltage of the sensor in the electric field environment is output through the contact wire.

Said one adopts contact type and non-contact type sensor, including signal acquisition module, contact type signal conditioning circuit, non-contact type signal conditioning circuit, signal processing circuit, sound and light alarm circuit, bluetooth sending module and mobile phone monitoring part; Two-way signals output by contact and non-contact sensors.

The signal acquisition module respectively collects the signal of the contact-type electricity examination by the contact-type metal probe, and collects the signal of the non-contact type electricity-examination by the flat capacitive electric field sensor.

The contact signal conditioning circuit includes a current limiting protection circuit, a current scaling module circuit and a voltage stabilization filter circuit;

The non-contact signal conditioning circuit includes a step-down circuit, a signal follower circuit, a filter circuit and a rectifier

The circuit is used for conditioning the induced voltage signal output by the flat capacitive electric field sensor;

The signal processing circuit adopts a single-chip microcomputer to simultaneously receive the voltage signals output by the two sensor signal conditioning circuits;

The bluetooth sending module adopts bluetooth chip 4.0 based on BLE technology, and sends the data output by the processor to the mobile phone terminal by wireless;

The mobile phone monitoring is to establish a bluetooth connection with the electroscope through a mobile phone client App, and the electroscope sends the data of the contact and non-contact electroscope results to the mobile phone through bluetooth, and is parsed by the mobile phone client App and displayed respectively, and output. Vibration and voice prompts.

The voltage divided by the stray capacitance between the contact metal probe and the electroscope ground is output to the ADC1 port of the single-chip MCU after passing through the current limiting protection circuit, the current scaling circuit and the voltage-stabilizing filter circuit; The step-down circuit, filter circuit, and rectifier circuit are output to the ADC2 port of the single-chip MCU; the single-chip computer outputs the corresponding sound and light alarm signal after AD conversion of the input signals of the ADC1 port and ADC2 port, and then judged by the program.

The non-contact signal conditioning circuit is composed of a resistor R1 and a resistor R2 to form a resistor divider and an impedance matching circuit. The resistor R1 and the resistor R2 are large resistors of 51MΩ and 10MΩ, respectively. Impedance matching is carried out, and the ratio of the two forms a voltage divider ratio of 1/6.1, which reduces the output voltage of the sensor to the range that can be read by the microcontroller; the operational amplifier U1 is a voltage follower circuit, which increases the input resistance and reduces the output resistance. Improve the load capacity of the circuit; resistor R3, resistor R4, resistor R5, resistor R6, capacitor C1, capacitor C2 and op amp U2 form an active second-order low-pass filter circuit to filter out high-frequency electromagnetic interference signals received by the sensor; The remaining circuit is a precision rectifier circuit, which rectifies the weak voltage signal and reads the signal of the single-chip microcomputer.

In the contact signal conditioning circuit, R13 is a large resistance of 1MΩ, which limits the current to protect the subsequent circuit; the resistance R14, the resistance R15, and the triode Q1 form a current scaling module. When the contact probe touches the charged body, the triode Q1 will periodically conduct; Resistor R16, resistor R17, resistor R18, capacitor C3 and capacitor C4 form a voltage-stabilizing filter circuit, so that the voltage output by the periodic on-off transistor Q1 can be output stably, and the ADC2 port can obtain a stable voltage.

The sound and light alarm circuit uses four LED lights for light alarm, which are located at the bottom of the electroscope shell to form a ring-shaped alarm LED light; the LED lights and the buzzer in the alarm circuit are driven by triodes. The voltage divider circuit composed of resistor R30 and resistor R31 in the Bluetooth sending module circuit, the output voltage AD is used as the reference voltage for the Bluetooth chip to monitor the remaining power, R32 and KEY form a voltage pull-up circuit, when the KEY is pressed, the Bluetooth module restarts; U1 is The Bluetooth chip, TXD1 and RXD1 are respectively connected to the sending port TXD and the receiving port RXD of the microcontroller for data transmission.

Compared with the prior art, the advantages and beneficial effects of the present utility model are as follows:

The sensor of the utility model has the characteristics of simple structure and convenient operation, can judge whether the current alarm type is a contact type alarm or a non-contact type alarm according to the frequency of the alarm signal, and can also judge the electroscope and the equipment to be tested according to the different frequencies of the alarm signal distance. The bluetooth communication and mobile phone monitoring of the utility model can enable the guardians to know the results of the electricity inspection in real time, and provide necessary safety reminders to the electricity inspection and maintenance personnel. The electric inspection method of the utility model using the contact and non-contact sensors can greatly improve the reliability and reliability of the electric inspection result, overcome the shortcomings of the traditional electroscope refusal to alarm and false alarm, and increase the power inspection maintenance. personnel safety.

The utility model judges the charged condition of the current device to be tested and the distance between the electroscope and the current device to be tested according to the magnitude of the output voltage of the contact type signal conditioning circuit and the non-contact type signal conditioning circuit, and simultaneously transmits the electricity detection result wirelessly via Bluetooth. The method can be sent to the monitoring terminal of the mobile phone for monitoring by the monitoring personnel, so as to ensure the safety of the electric inspection personnel. The electric inspection method of the utility model can not only reduce the alarm circuit from two circuits to one circuit, but also reduce the interference caused by the simultaneous alarming of the two alarm circuits. It can also accurately determine the current alarm mode. At the same time, the introduction of the novel electrical testing method and dual sensors in the utility model greatly improves the correctness of the electrical testing results, reduces the false alarm rate, and can effectively detect whether the device to be tested is charged.

Description of drawings

In order to facilitate those skilled in the art to understand and implement the present utility model, the present utility model is further described in detail below with reference to the accompanying drawings and specific embodiments, but it should be understood that the protection scope of the present utility model is not limited by the specific embodiments.

Fig. 1 is the sensor structure schematic diagram of the present invention;

Fig. 2 is the working principle diagram of the present utility model;

Fig. 3 is the non-contact signal conditioning circuit of the present invention;

Fig. 4 is the contact type signal conditioning circuit of the present invention;

Fig. 5 is the sound and light alarm circuit of the present utility model;

Fig. 6 is the flow chart of the signal processing module of the present invention;

Fig. 7 is the bluetooth sending module circuit of the present utility model;

Fig. 8 is the interface layout diagram of the mobile phone monitoring terminal of the present invention;

Fig. 9 is the working flow chart of the mobile phone monitoring terminal of the present invention;

Fig. 10 is the electric inspection flow of the electric inspection method of the present invention.

In the figure: contact metal probe 1, flat capacitive electric field sensor 2, fixing bolt 3, non-contact wire 4, electroscope ground 5, contact wire 6.

Detailed ways

As shown in FIG. 1 , FIG. 1 is a structural diagram of the sensor of the present invention. The utility model includes a contact metal probe 1 , a flat capacitive electric field sensor 2 , a fixing bolt 3 , a non-contact wire 4 , an electroscope ground 5 , and a contact wire 6 . Among them, the combination of the contact metal probe 1 and the flat capacitive electric field sensor 2, in which the two sensors work independently, after the contact probe 1 contacts the charged object, the stray capacitance between the contact metal probe 1 and the electroscope ground 5 is divided into A voltage that is used for detection by subsequent contact signal conditioning circuits. The contact probe is connected with the electroscope ground 5 through the contact wire 6 and outputs voltage. The flat capacitive electric field sensor 2 is annular and is fixedly connected to the contact metal probe 1 . The induced voltage of the flat capacitive electric field sensor 2 in the electric field environment is output through the contact wire 6 for subsequent circuit detection.

One end of the contact metal probe 1 is inserted into the annular space in the middle of the flat capacitive electric field sensor 2 to be fixedly connected by fixing bolts 3. The contact probe is connected to the contact wire 6 and the electroscope ground 5 to output voltage to provide detection for the contact sensor. Signal; the induced voltage of the flat capacitive electric field sensor 2 provides detection signals for the non-contact sensor through the non-contact wires 4 connected to the upper and lower ends of the flat capacitive electric field sensor 2 .

When using the contact-type and non-contact-type sensors of the utility model for actual electricity inspection, the operation method includes: a signal acquisition module, a contact-type signal conditioning circuit, a non-contact signal conditioning circuit, a signal processing circuit, an acousto-optic alarm circuit, Bluetooth sending module and mobile phone monitoring part. The utility model collects the two-way signals output by the contact type and the non-contact type sensor, and performs logical judgment on the two-way signals, which can greatly improve the correctness and reliability of the electrical inspection result.

The signal acquisition modules respectively use the contact metal probe 1 to acquire the signal acquisition of the contact type electricity examination, and the flat capacitive electric field sensor 2 is used for the signal acquisition of the non-contact type electricity examination.

The contact signal conditioning circuit includes a current limiting protection circuit, a current scaling module circuit and a voltage stabilization filter circuit.

The non-contact signal conditioning circuit includes a step-down circuit, a signal follower circuit, a filter circuit and a rectifier circuit, and is mainly used for conditioning the induced voltage signal output by the flat capacitive electric field sensor.

The signal processing circuit adopts a single-chip microcomputer to simultaneously receive the voltage signals output by the two channels of sensor signal conditioning circuits, and respectively calculates the effective values of the two channels of voltage signals, performs logical judgment on the magnitude of the calculated two channels of voltage signals, and outputs the corresponding frequency. Different alarm signals. According to the frequency of the alarm signal, it is judged whether the alarm mode is a contact alarm or a non-contact alarm. When the sound and light alarm frequency is 2Hz, it is a contact alarm. If the sound and light alarm frequency is greater than 5Hz, it is a non-contact alarm. It can also judge the distance between the electroscope and the object to be measured according to the different frequencies.

The bluetooth sending module adopts the bluetooth chip 4.0 based on BLE technology, and sends the data output by the processor to the mobile phone terminal by wireless means, and the monitoring software on the mobile phone terminal performs data processing.

The mobile phone monitoring is to help the on-site monitoring personnel to monitor the electrical inspection results of the maintenance personnel, so as to ensure the safety of the maintenance personnel.

The implementation of the mobile phone monitoring terminal is as follows: establish a Bluetooth connection with the electroscope through a mobile phone client App, and the electroscope sends the data of the contact and non-contact electroscope results to the mobile phone through Bluetooth, and the mobile phone client App parses and separates the data. Display, and output vibration and voice prompts. That is: the mobile phone monitoring terminal is used for the safety monitoring of the on-site inspection personnel by the monitoring personnel. The realization method is to receive the bluetooth data through the mobile phone client, and then analyze the bluetooth data protocol to obtain the contact and non-contact electrical inspection data. , The contact and non-contact data are displayed dynamically through the dial animation respectively, and the contact and non-contact data are logically judged. According to the result of the logical judgment, the mobile phone will issue different voice alarm reminders and vibration reminders. According to the prompts of the mobile phone monitoring terminal, the guardians will monitor the inspection and maintenance personnel and provide necessary safety reminders.

As shown in FIG. 2, FIG. 2 is a working principle diagram of the present invention. The voltage divided by the stray capacitance between the contact metal probe 1 and the electroscope ground 5 is output to the ADC1 port of the microcontroller MCU after passing through the current limiting protection circuit, the current scaling circuit and the voltage stabilization filter circuit. The induced voltage of the flat capacitive electric field sensor 2 is output to the ADC2 port of the single-chip MCU after passing through the step-down circuit, the filter circuit and the rectifier circuit. After the single-chip microcomputer converts the input signals of ADC1 port and ADC2 port through AD conversion, and then judges by the program, it outputs the corresponding sound and light alarm signal.

As shown in FIG. 3 , FIG. 3 is a non-contact signal conditioning circuit of the present invention. Among them, resistor R1 and resistor R2 form a resistor divider and impedance matching circuit. Resistor R1 and resistor R2 are large resistors of 51MΩ and 10MΩ, respectively. They use large resistors to match the impedance of the flat capacitive electric field sensor and improve the electric field sensor. At the same time, the ratio of the two forms a voltage divider ratio of 1/6.1, which reduces the output voltage of the sensor to the range that can be read by the microcontroller. The operational amplifier U1 is a voltage follower circuit, which improves the load capacity of the circuit by increasing the input resistance and reducing the output resistance. Resistor R3, resistor R4, resistor R5, resistor R6, capacitor C1, capacitor C2 and operational amplifier U2 form an active second-order low-pass filter circuit to filter out high-frequency electromagnetic interference signals received by the sensor. The remaining circuit in Figure 3 is a precision rectifier circuit, which is used to rectify weak voltage signals, which is convenient for the signal reading of the single-chip microcomputer.

As shown in FIG. 4, FIG. 4 is the contact signal conditioning circuit of the present invention, and R13 in the figure is a large resistance of 1MΩ, which is used to limit the current to protect the subsequent circuit. The resistor R14, the resistor R15, and the transistor Q1 form a current scaling module. When the contact probe touches the charged body, the transistor Q1 will periodically conduct. Resistor R16, resistor R17, resistor R18, capacitor C3 and capacitor C4 form a voltage-stabilizing filter circuit, so that the voltage output by the periodic on-off transistor Q1 can be output stably, and the ADC2 port can obtain a stable voltage.

As shown in Figure 5, Figure 5 is the sound and light alarm circuit of the present invention, which uses four LED lights for light alarm, which are located at the bottom of the electroscope shell to form a ring-shaped alarm LED light. The LED lights and buzzer in the alarm circuit are driven by triodes.

As shown in Figure 6, Figure 6 is the process flow of the signal processing module of the present invention. After the circuit is powered on, the single-chip microcomputer initializes the ADC1 port, the ADC2 port and the timer TIM1, and the TIM1 is initialized to be interrupted once for 100us, and each interrupt is read once ADC1 port and ADC2 port, and calculate the effective value every 100 data to obtain ADC1 port and ADC2 port, and then according to the conversion coefficient k1 of the output voltage of the flat capacitive electric field sensor to the ADC1 port and the output voltage of the contact signal conditioning circuit to the ADC2 port The conversion coefficient k2 is used to obtain the output voltage of the flat capacitive electric field sensor U1=ADC1*k1 and the output voltage of the contact signal conditioning circuit U2=ADC2*k2, and logically judge the converted voltage U1 and voltage U2: when the voltage U2>1.5V , it means that the metal contact probe is in contact with the charged body, and the low-frequency sound and light alarm frequency of 2Hz is output to indicate that the contact is electrified. When U2<=1.5V, then judge the size of the voltage U1, and compare it with the alarm threshold voltage U0.7, voltage U0.5, voltage U0.3, and voltage U0.1 of each distance obtained from the experimental results. If the voltage If U1<U0.7, it will not alarm, otherwise, the sound and light alarm signal of the corresponding frequency will be issued according to the voltage range in which it is located, and the higher the voltage of the voltage U1, the higher the sound and light alarm frequency.

As shown in Figure 7, Figure 7 is the bluetooth sending module circuit of the present invention, the voltage divider circuit composed of resistor R30 and resistor R31 in the figure, the output voltage AD is used as a reference voltage for the Bluetooth chip to monitor the remaining power, in the figure R32 and KEY A voltage pull-up circuit is formed. When the KEY is pressed, the Bluetooth module restarts. U1 is a Bluetooth chip, and TXD1 and RXD1 are respectively connected to the sending port TXD and the receiving port RXD of the microcontroller for data transmission.

As shown in Figure 8, Figure 8 is the interface layout diagram of the mobile phone monitoring terminal of the present invention. As shown in the figure, the monitoring terminal interface layout includes three parts, which respectively display the connection status of the Bluetooth device, the voltage value of the contact-type electricity test and its The dial display, the voltage value of the non-contact electroscope and its dial display. The maximum range of the dial is the voltage value when the distance between the electroscope and the live equipment is 0.

As shown in Fig. 9, Fig. 9 is the working flow chart of the mobile phone monitoring terminal of the present utility model, before starting the electroscope, the power grid monitoring personnel use the mobile phone terminal to open the bluetooth to search for the bluetooth equipment, and after detecting the required electroscope bluetooth equipment, carry out Bluetooth connection, after connecting to the Bluetooth device, Bluetooth opens a new thread to analyze the data protocol, and analyzes the voltage value of the contact type test and the voltage value of the non-contact type test. The mobile phone monitoring terminal interface will display the current contact type and non-contact type. voltage value and dial animation. Then make a logical judgment on the analyzed contact and non-contact voltage values. When the contact voltage reaches 1.0V, it means that the electroscope is in contact with the high-voltage equipment and the high-voltage equipment is charged. , Dangerous!" voice prompt. Otherwise, judge whether the non-contact electroscope voltage is greater than 1.4V. When the non-contact electroscope voltage is greater than 1.4V, indicating that the distance between the electroscope and the live equipment is less than the safe distance of 0.7m, the mobile phone vibrates and emits "non-contact live, Do not approach" voice prompt. Otherwise, the phone will not give voice and vibration prompts.

As shown in FIG. 10 , FIG. 10 is the electric inspection flow of the electric inspection method of the present invention. Specifically, when the electroscope in the utility model is used to approach the device to be tested, when the distance from the device to be tested is 0.1m-0.7m, if the electroscope emits a sound and light alarm with a frequency higher than 5Hz, and the closer the distance to the device to be tested is, the sound and light alarm If the alarm frequency is higher, it means that the non-contact electroscope has issued an alarm, and the equipment to be tested may be charged. Further contact the metal contact probe of the electroscope with the equipment to be tested. If the sound and light alarm frequency of the electroscope is reduced to 2Hz at this time, it means that The contact-type electroscope issues an alarm, and the equipment to be tested is indeed charged. Otherwise, if the electroscope still emits a high-frequency sound and light alarm when it is in contact, it means that the non-contact electroscope still issues an alarm, and the equipment to be tested may not be electrified. Perform a power test on other nearby devices to confirm whether the device under test is not charged. If the electroscope does not issue an audible and visual alarm when it is 0.1m-0.7m away from the device to be tested, it means that the non-contact electroscope does not issue an alarm, and the device to be tested may not be electrified. Further connect the metal probe of the electroscope to the device to be tested. Contact, if the electroscope still does not emit sound and light alarm at this time, it means that the device under test is indeed not charged, otherwise, it means that the device under test may be charged, and re-test.

Claims (8)

1. Adopt contact type and non-contact type sensor, it is characterized in that: one end of the contact type metal probe is inserted and connected in the flat capacitive electric field sensor to be connected, and the upper and lower ends of the electric field sensor are respectively connected to non-contact type wires; The electroscope ground is connected, and the contact probe is connected to the contact wire and the electroscope ground; The flat capacitive electric field sensor is annular, with an annular space in the middle. The annular space is fixedly connected with the contact metal probe through fixing bolts, and the contact probe is connected to the contact wire and the output voltage of the electroscope to provide detection for the contact sensor. Signal; the induced voltage of the flat capacitive electric field sensor provides detection signals for the non-contact sensor through the non-contact wires connected to the upper and lower ends of the flat capacitive electric field sensor; The contact metal probe is combined with a flat capacitive electric field sensor, wherein the two sensors work independently, the contact probe contacts a charged object, and the stray capacitance between the contact metal probe and the electroscope ground is divided into a voltage; the flat capacitive electric field The induced voltage of the sensor in the electric field environment is output through the contact wire. 2. A contact type and non-contact type sensor according to claim 1, characterized in that it comprises a signal acquisition module, a contact type signal conditioning circuit, a non-contact type signal conditioning circuit, a signal processing circuit, and an acousto-optic alarm circuit , Bluetooth sending module and mobile phone monitoring part; collect two-way signals output by contact and non-contact sensors. 3. A kind of adopting contact type and non-contact type sensor according to claim 2, it is characterized in that: described signal acquisition module collects the signal of contact type electroscope by contact type metal probe respectively, and flat capacitive electric field sensor collects non-contact type electric field sensor. Contact electroscope signal. 4. A contact type and non-contact type sensor according to claim 2, wherein the contact type signal conditioning circuit comprises a current limiting protection circuit, a current scaling module circuit and a voltage stabilization filter circuit; The non-contact signal conditioning circuit includes a step-down circuit, a signal follower circuit, a filter circuit and a rectifier The circuit is used for conditioning the induced voltage signal output by the flat capacitive electric field sensor; The signal processing circuit adopts a single-chip microcomputer to simultaneously receive the voltage signals output by the two sensor signal conditioning circuits; The bluetooth sending module adopts bluetooth chip 4.0 based on BLE technology, and sends the data output by the processor to the mobile phone terminal by wireless; The mobile phone monitoring is to establish a bluetooth connection with the electroscope through a mobile phone client App, and the electroscope sends the data of the contact and non-contact electroscope results to the mobile phone through bluetooth, and is parsed by the mobile phone client App and displayed respectively, and output. Vibration and voice prompts. 5. A contact type and non-contact type sensor according to claim 1, characterized in that: the voltage divided by the stray capacitance between the contact type metal probe and the electroscope ground passes through the current limiting protection circuit, and the current scales The circuit and voltage stabilization filter circuit are output to the ADC1 port of the single-chip MCU; the flat capacitive electric field sensor (2) The induced voltage is output to the ADC2 port of the single-chip MCU after the step-down circuit, filter circuit and rectification circuit; After the port input signal is converted by AD, and then judged by the program, the corresponding sound and light alarm signal is output. 6. A contact type and non-contact type sensor according to claim 2, characterized in that: the non-contact type signal conditioning circuit is composed of a resistor R1 and a resistor R2 to form a resistor divider and an impedance matching circuit, and the resistor R1 and resistance R2 are large resistances of 51MΩ and 10MΩ, respectively. The two use large resistances to match the impedance of the flat capacitive electric field sensor. At the same time, the ratio of the two forms a voltage divider ratio of 1/6.1. The range of reading; the operational amplifier U1 is a voltage follower circuit, and the load capacity of the circuit is improved by increasing the input resistance and reducing the output resistance; resistor R3, resistor R4, resistor R5, resistor R6, capacitor C1, capacitor C2 and op amp U2 constitutes an active second-order low-pass filter circuit to filter out high-frequency electromagnetic interference signals received by the sensor; the remaining circuit is a precision rectifier circuit, which rectifies weak voltage signals and reads the signals of the single-chip microcomputer. 7. A contact-type and non-contact-type sensor according to claim 2, characterized in that: in the contact-type signal conditioning circuit, R13 is a large resistance of 1MΩ, limiting current to protect subsequent circuits; resistance R14, resistance R15 , Triode Q1 constitutes a current scaling module, when the contact probe touches the charged body, the triode Q1 will be turned on periodically; resistor R16, resistor R17, resistor R18, capacitor C3 and capacitor C4 form a voltage stabilizing filter circuit, which makes the cycle on and off. The voltage output by the transistor Q1 can be output stably, and the ADC2 port gets a stable voltage. 8. a kind of adopting contact type and non-contact type sensor according to claim 2, it is characterized in that: described sound and light alarm circuit, adopts four LED lights to carry out light alarm, is located at the bottom of electroscope shell, forms ring-shaped alarm LED LED lights and buzzers in the alarm circuit are driven by triodes; the voltage divider circuit composed of resistor R30 and resistor R31 in the Bluetooth sending module circuit, the output voltage AD is used as a reference voltage for the Bluetooth chip to monitor the remaining power, R32 and KEY A voltage pull-up circuit is formed. When the KEY is pressed, the Bluetooth module restarts; U1 is a Bluetooth chip, and TXD1 and RXD1 are respectively connected to the sending port TXD and the receiving port RXD of the microcontroller for data transmission.

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