CN103513222B - Ammeter rapid stealing detecting instrument - Google Patents

Abstract

A fast electric meter theft detection instrument, comprising a host housing, a clamp meter and a working circuit board, the host housing is provided with a liquid crystal screen observation window, the clamp meter is composed of a clamp head housing and an iron core, the The working circuit board described above is installed in the host casing, and the feature is that the working circuit board includes a main control CPU, a front-end signal conditioning circuit, a keyboard circuit, a voice circuit, a power supply circuit and an LCD liquid crystal interface circuit. Its advantages are that the anti-theft instrument is a miniature hand-held electrical measuring instrument suitable for the field, which is easy to carry, easy to connect, less likely to be disturbed when collecting signals, accurate measurement data, simple operation, simple circuit structure, and the internal data calculation process of the circuit Simple, fast calculation speed, can quickly judge whether the electric energy meter is normal, whether there is electricity stealing or not, and at the same time, it sends out beautiful human voice prompts, which is more humanized and easier to use.

Description

Fast Meter Theft Checker

technical field

The invention relates to an electric meter theft detector, in particular to a fast electric meter theft detector, which is suitable for on-site measurement of the electric parameters of the electric energy meter, so as to judge whether the electric energy meter is normal, whether there is electricity stealing or not.

Background technique

At present, most of the existing on-site detection devices for electric energy meters use a structure in which the main unit and the clamp meter are separated, and the clamp meter and the main unit must be connected by a very long wire. It is disturbed, the operation is complicated, the measurement data is not accurate, and it is very inconvenient to use. In addition, although there are also electric energy meter burglary detectors that integrate clamp meters and hosts, their circuit structures are relatively complicated, and the data calculation process inside the circuit is also very complicated, and the calculation speed is relatively slow; therefore, it is more troublesome to maintain. It is convenient to quickly check electricity theft.

Contents of the invention

The purpose of the present invention is to design a quick meter burglary detection instrument which integrates a clamp meter and a host computer. Interference, accurate measurement data, simple operation, simple circuit structure, simple data calculation process inside the circuit, fast calculation speed, can quickly determine whether the electric energy meter is normal, whether there is or is not stealing behavior, and it is easier to use.

The purpose of the present invention can be achieved through the following technical solutions:

The electric meter rapid detection instrument includes a host housing, a clamp meter and a working circuit board. The host housing is provided with an LCD viewing window. The clamp meter is composed of a clamp head housing and an iron core. The working circuit board is installed in the host housing, and it is characterized in that: the working circuit board includes a main control CPU, a front-end signal conditioning circuit, a keyboard circuit, a voice circuit, a power supply circuit and an LCD liquid crystal interface circuit, and the main control CPU Microcontroller U5, external clock circuit, pull-down resistor R17, CPU power-on reset circuit, CPU power supply VCC decoupling capacitor, polarized capacitor E5, AD interface analog power supply filter circuit and 0 ohm resistor R21, among them, the microcontroller The model of U5 is STM32F100CBT6, there are 8M crystal oscillator Y1 and capacitors C7 and C8 in the external clock circuit, resistor R18 and capacitor C9 in the CPU power-on reset circuit, capacitors C10, C11 and C12 in the CPU power supply VCC decoupling capacitor, AD interface There are inductance L2, capacitor C13 and polarized capacitor E6 in the analog power filter circuit; there are voltage followers U2A, U2C and U2D in the four-channel high-precision operational amplifier in the front-end signal conditioning circuit, AC current sampling input terminal P1, AC voltage Input terminal P2, resistors R1, R3~R10 and R12, capacitors C1~C3, and clamping diodes D1 and D3~D5, the model of the four-channel high-precision operational amplifier is SGM8554, and the models of clamping diodes D1 and D3~D5 are It is IN4148; there are control keys KEY1 and KEY2 and resistors R11 and R13 in the keyboard circuit; there are audio amplifier chips U3, polarized capacitors E3 and E4, capacitors C4 and C5, resistors R14 and R15, and speaker SP1 in the voice circuit. The model of power amplifier chip U3 is SGM4890YMS; there are battery BT1, switching voltage regulator U1, polarized capacitors E1 and E2, diode D2, inductor L1, resistor R2 and dial switch S1 in the power circuit, and the switching voltage regulator U1 The model is LM2596S-3.3, the model of diode D2 is STPS2L25U, the model of inductor L1 is DO3316P-104, the model of DIP switch S1 is SW DIP-6; LCD liquid crystal interface circuit has LCD driver U4, resistor R16, capacitor C6 and 4-digit 7-segment digital LCD screen DS1, the model of its LCD driver U4 is HT1621B, and the model of 4-digit 7-segment digital LCD screen DS1 is GDC8310;

The connection relationship is: in the main control CPU, the first pin of the microcontroller U5 is connected to the 3.3V DC voltage VCC3.3 generated by the power supply circuit, and the 23rd, 35th and 47th pins of the microcontroller U5 are connected to each other Connect the digital ground after short circuit, the two ends of the external clock circuit crystal oscillator Y1 are respectively connected to the 5th and 6th pins of the microcontroller U5, one end of the pull-down resistor R17 is connected to the digital ground, and the other end is connected to the microcontroller U5 The 44th pin, one end of the resistor R18 and the capacitor C9 in the CPU power-on reset circuit are connected to the seventh pin of the microcontroller U5, the other end of the resistor R18 is connected to the 3.3V DC voltage VCC3.3, and the other end of the capacitor C9 Connect to digital ground, one end of capacitors C10, C11 and C12 in CPU power supply VCC decoupling capacitor are respectively connected to the 24th, 36th and 48th pins of microcontroller U5, and the other ends are all connected to digital ground, with polarized capacitors The positive pole of E5 is connected to the 3.3V DC voltage VCC3.3, and is connected to the 24th, 36th and 48th pins of the microcontroller U5 at the same time, the negative pole of the polarized capacitor E5 is connected to the digital ground, and the analog power supply filter circuit of the AD interface One end of the internal inductor L2 is connected to the 3.3V DC voltage VCC3.3, the other end of the inductor L2 is connected to the 9th pin of the microcontroller U5, and an analog power supply voltage signal AVCC is drawn out, and one end of the capacitor C13 is connected to the polar capacitor E6 The positive pole is connected to the other end of the inductor L2 at the same time, the other end of the capacitor C13 and the negative pole of the polarized capacitor E6 are connected to the 8th pin of the microcontroller U5, and the 0 ohm resistor R21 is a single-point connection between the digital ground and the analog ground Resistor with one end connected to pin 8 of the microcontroller U5 and the other end connected to digital ground; in the front-end signal conditioning circuit, the positive supply connections of the voltage followers U2A, U2C, and U2D in the four-channel high-precision operational amplifier Both terminals are connected to the analog power supply voltage signal AVCC drawn from the main control CPU, wherein, a capacitor C2 is also connected between the positive power connection terminal of the voltage follower U2A and the analog ground, and the negative power supply connection of the voltage followers U2A, U2C and U2D Both terminals are connected to the analog ground, the voltage follower U2D and resistors R6 and R9 constitute a 1.65V voltage reference generating circuit, one end of the resistor R6 is connected to one end of the resistor R9, and then connected to the inverting input terminal of the voltage follower U2D, the resistor The other end of R6 is connected to the analog power supply voltage signal AVCC, the other end of the resistor R9 is connected to the analog ground, the output end of the voltage follower U2D is connected to its non-inverting input end, and the 1.65V voltage reference signal REF is drawn out, and the AC current sampling input terminal P1 is connected to Wind both ends of the enameled wire output wire on the iron core of the clamp meter. The first pin of the AC current sampling input terminal P1 is connected to one end of the resistor R3, and the second pin of the AC current sampling input terminal P1 is connected to the other end of the resistor R3 and the resistor One end of R4, the other end of resistor R4 is connected to 1.65V voltage reference signal REF, the positive pole of clamping diode D1 is connected to the negative pole of clamping diode D3 and one end of resistor R3, and then connected to To the non-inverting input terminal of the voltage follower U2A, the cathode of the clamping diode D1 is connected to the analog power supply voltage signal AVCC, the anode of the clamping diode D3 is connected to the analog ground, the output terminal of the voltage follower U2A is connected to its inverting input terminal, and at the same time Connect one end of the resistor R1, the other end of the resistor R1 is connected to one end of the capacitor C1, the other end of the capacitor C1 is connected to the analog ground, the AC voltage input terminal P2 is connected to the AC 0-400V power supply, the first and second leads of the AC voltage input terminal P2 The pins are respectively connected to one end of the resistor R5 and the resistor R10, the other end of the resistor R5 and the resistor R10 are respectively connected to the two ends of the resistor R8, one end of the resistor R12 is connected to one end of the resistor R10, and the other end of the resistor R12 is connected to the 1.65V voltage reference signal REF, The anode of the clamping diode D4 is connected to the negative terminal of the clamping diode D5 and the other end of the resistor R10, and then connected to the non-inverting input terminal of the voltage follower U2C, and the negative terminal of the clamping diode D4 is connected to the analog power supply voltage signal AVCC to clamp The anode of the diode D5 is connected to the analog ground, the output terminal of the voltage follower U2C is connected to its inverting input terminal, and one end of the resistor R7 is connected at the same time, the other end of the resistor R7 is connected to one end of the capacitor C3, and the other end of the capacitor C3 is connected to the analog ground ; Between the front-end signal conditioning circuit and the main control CPU, the other end of the resistor R1 is connected to the 12th pin of the microcontroller U5, and the other end of the resistor R7 is connected to the 13th pin of the microcontroller U5; in the keyboard circuit , the 1st, 2nd, 4th and 5th terminals of the control button KEY1 are short-circuited with each other, the 3rd and 6th terminals of the control button KEY1 are short-circuited and connected to one end of the resistor R11, and the other end of the resistor R11 is connected to 3.3V DC voltage VCC3.3, and connect one end of the resistor R13 at the same time, the other end of the resistor R13 is connected to the second and third terminals of the control button KEY2, and the first and fourth terminals of the control button KEY2 are short-circuited; the keyboard circuit and the main control CPU Between, the 5th terminal of the control button KEY1 is connected to the 32nd pin of the microcontroller U5, the 1st terminal of the control button KEY2 is connected to the 33rd pin of the microcontroller U5; in the voice circuit, the audio power amplifier chip U3 The 6th pin is connected to the 3.3V DC voltage VCC3.3, and at the same time connected to the positive pole of the polarized capacitor E3, the negative pole of the polarized capacitor E3 is connected to the 7th pin of the audio power amplifier chip U3, and the 1st pin of the audio power amplifier chip U3 The pin is connected to one end of the capacitor C4, the other end of the capacitor C4 is connected to the negative pole of the polarized capacitor E4, and connected to the digital ground, and the positive pole of the polarized capacitor E4 is connected to the second and third pins of the audio power amplifier chip U3 Connection, the 4th pin of the audio power amplifier chip U3 is connected to one end of the resistor R14 and the resistor R15, the other end of the resistor R14 is connected to one end of the capacitor C5, and the other end of the resistor R15 is connected to the 5th pin of the audio power amplifier chip U3, the speaker SP1 The two ends of the capacitor C5 are connected to the 5th and 8th pins of the audio power amplifier chip U3; between the voice circuit and the main control CPU, the other end of the capacitor C5 is connected to the microcontroller U5 The 14th pin of the audio power amplifier chip U3 is connected to the 15th pin of the microcontroller U5; in the power supply circuit, the 1st pin of the switching voltage regulator U1 is connected to the 1st terminal of the DIP switch S1 , and connect the positive pole of the polarized capacitor E2 at the same time, connect the negative pole of the polarized capacitor E2 to the negative pole of the battery BT1, and connect the 3rd and 5th pins of the switching voltage regulator U1 at the same time, the 3rd pin of the switching voltage regulator U1 The pin is connected to the digital ground, the positive pole of the battery BT1 is connected to the second terminal of the dial switch S1, the second pin of the switching voltage regulator U1 is connected to the negative pole of the diode D2 and one end of the inductor L1, the positive pole of the diode D2 is connected to the digital ground, and At the same time, it is connected to the negative pole of the polarized capacitor E1, and the positive pole of the polarized capacitor E1 is connected to the other end of the inductor L1. The other end of the inductor L1 generates a 3.3V DC voltage VCC3.3, and is connected to the fourth lead of the switching voltage regulator U1 at the same time. After the 5th and 7th terminals of the DIP switch S1 are short-circuited, connect one end of the resistor R2, and the other end of the resistor R2 is connected to the other end of the inductor L1; between the power circuit and the main control CPU, the DIP switch S1 The 6th and 8th terminals of the LCD driver U4 are connected to the 42nd and 43rd pins of the microcontroller U5 respectively; in the LCD liquid crystal interface circuit, the 8th pin of the LCD driver U4 is connected to one end of the resistor R16, and the other end of the resistor R16 is connected to 3.3V DC voltage VCC3.3, and connect the 9th pin of the LCD driver U4 and one end of the capacitor C6 at the same time, the other end of the capacitor C6 is connected to the digital ground, and the 1st to 4th pins of the 4-digit 7-segment digital LCD screen DS1 The 16th to 13th pins of the LCD driver U4 are respectively connected, and the 5th to 13th pins of the 4-digit 7-segment digital LCD liquid crystal screen DS1 are respectively connected to the 48th to 40th pins of the LCD driver U4; LCD liquid crystal interface circuit Between the main control CPU, the 1st to 4th pins of the LCD driver U4 are respectively connected to the 4th, 3rd, 2nd and 46th pins of the microcontroller U5;

The internal calculation process of the anti-theft instrument to measure the incoming current Ia of the live wire or the outgoing current Ib of the neutral line is: input the analog signal of the incoming current of the live line or the analog signal of the outgoing current of the neutral line in the anti-theft instrument, and pass through the internal working circuit board of the anti-theft instrument After conditioning by the front-end signal conditioning circuit on the circuit board, it is directly input to the microcontroller U5 of the main control CPU1. After the internal AD conversion of the microcontroller U5, the instantaneous current sampling value of the live wire entering the line or the neutral line exiting the line is obtained. The instantaneous current sampling value of the neutral line outgoing line is calculated by the microcontroller U5 to obtain the current effective value of the live line incoming line or the neutral line outgoing line, that is, the measured live line incoming current Ia or the neutral line outgoing current Ib; the live line incoming current Ia and the neutral line current Ib After the outgoing line current Ib is measured on both sides, the anti-theft detector judges according to the following judgment basis, and the voice circuit gives a corresponding beautiful human voice voice prompt according to the judgment result; the judgment basis is: when Ia / Ib -1 > 15% When Ia / Ib -1 < 15%, it prompts "There is an outside line connected", and the above two situations indicate that the state of the energy meter is not normal, and there may be electricity theft.

In the power supply circuit of the present invention, the battery BT1 is a 9V alkaline battery.

In the present invention, in the power supply circuit, the dial switch S1 is a dial dial switch.

Between the LCD interface circuit of the present invention and the main control CPU, the 1st to 4th pins of the LCD driver U4 are respectively connected to the 4th, 3rd, 2nd and 46th pins of the microcontroller U5 through the SPI communication interface .

The advantages of the present invention are: 1) The burglary detection instrument is a miniature hand-held electric measuring instrument suitable for the field, which is easy to carry; 2) It adopts the integrated design of the clamp meter and the host, and adopts a 32-bit Cortex-M3 core micro-control The circuit structure is simple, without power failure during use, without changing the circuit wiring of the metering electric energy meter, as long as the clamp meter is respectively inserted into the live line and the neutral line of the electric energy meter, the live line of the electric energy meter circuit can be measured. The current and the current of the zero line outlet, and then through the rapid calculation of the main control CPU of the steal detector, quickly judge whether the electric energy meter is normal, whether there is electricity stealing behavior, and at the same time send out a beautiful human voice voice prompt, easy to connect, simple to operate, and the internal circuit The data calculation process is simple, the calculation speed is fast, it is more user-friendly, and it is easier to use; 3) The clamp meter wiring is short, which can avoid interference when collecting signals, and the measurement data is more accurate.

Description of drawings

Fig. 1 is the overall frame diagram of the working circuit board;

Figure 2 is a schematic diagram of the main control CPU;

Fig. 3 is a schematic diagram of the front-end signal conditioning circuit;

Fig. 4 is a schematic diagram of the keyboard circuit;

Fig. 5 is a schematic diagram of the voice circuit;

Fig. 6 is a schematic diagram of a power supply circuit;

Figure 7 is a schematic diagram of the LCD liquid crystal interface circuit.

detailed description

As shown in Fig. 1-7, this ammeter quick detection theft instrument, comprises main body housing, clamp meter and working circuit board, described main body housing is provided with liquid crystal screen observation window, and described clamp meter consists of clamp head housing body and an iron core, the working circuit board is installed in the main body casing, and the feature is: the working circuit board includes a main control CPU1, a front-end signal conditioning circuit 2, a keyboard circuit 3, a voice circuit 4, a power supply Circuit 5 and LCD liquid crystal interface circuit 6, the main control CPU1 has microcontroller U5, external clock circuit, pull-down resistor R17, CPU power-on reset circuit, CPU power supply VCC decoupling capacitor, polarized capacitor E5, AD interface analog power supply Filter circuit and 0 ohm resistor R21, among them, the model of microcontroller U5 is STM32F100CBT6, 8M crystal oscillator Y1 and capacitors C7 and C8 are in the external clock circuit, resistor R18 and capacitor C9 are in the CPU power-on reset circuit, and the CPU power supply VCC is turned off There are capacitors C10, C11 and C12 in the coupling capacitor, and an inductor L2, a capacitor C13 and a polarized capacitor E6 in the AD interface analog power supply filter circuit; the voltage follower U2A in the four-channel high-precision operational amplifier in the front-end signal conditioning circuit 2 , U2C and U2D, AC current sampling input terminal P1, AC voltage input terminal P2, resistors R1, R3~R10 and R12, capacitors C1~C3, and clamping diodes D1 and D3~D5, the model of the four-channel high-precision operational amplifier It is SGM8554, the models of clamping diodes D1 and D3~D5 are all IN4148; the keyboard circuit 3 has control keys KEY1 and KEY2 and resistors R11 and R13; the voice circuit 4 has an audio power amplifier chip U3 and polarized capacitors E3 and E4 , capacitors C4 and C5, resistors R14 and R15 and loudspeaker SP1, the model of its audio amplifier chip U3 is SGM4890YMS; the power supply circuit 5 has battery BT1, switching voltage regulator U1, polarized capacitors E1 and E2, diode D2, inductor L1, resistor R2 and DIP switch S1, the model of switching voltage regulator U1 is LM2596S-3.3, the model of diode D2 is STPS2L25U, the model of inductor L1 is DO3316P-104, and the model of DIP switch S1 is SWDIP-6; The LCD liquid crystal interface circuit 6 has an LCD driver U4, a resistor R16, a capacitor C6 and a 4-digit 7-segment digital LCD screen DS1. The model of the LCD driver U4 is HT1621B, and the model of the 4-digit 7-segment digital LCD screen DS1 is GDC8310;

The connection relationship is: in the main control CPU1, the first pin of the microcontroller U5 is connected to the 3.3V DC voltage VCC3.3 generated by the power supply circuit 5, and the 23rd, 35th and 47th pins of the microcontroller U5 Connect to the digital ground after shorting each other, the two ends of the external clock circuit crystal oscillator Y1 are respectively connected to the 5th and 6th pins of the microcontroller U5, one end of the pull-down resistor R17 is connected to the digital ground, and the other end is connected to the microcontroller U5 The 44th pin of the CPU power-on reset circuit, one end of the resistor R18 and the capacitor C9 are connected to the seventh pin of the microcontroller U5, the other end of the resistor R18 is connected to the 3.3V DC voltage VCC3.3, and the other end of the capacitor C9 One end is connected to the digital ground, and one end of the CPU power supply VCC decoupling capacitor inner capacitor C10, C11, and C12 is respectively connected to the 24th, 36th, and 48th pins of the microcontroller U5, and the other end is connected to the digital ground, with polarity The positive pole of the capacitor E5 is connected to the 3.3V DC voltage VCC3.3, and is connected to the 24th, 36th and 48th pins of the microcontroller U5 at the same time, the negative pole of the polarized capacitor E5 is connected to the digital ground, and the AD interface is used for analog power filtering One end of the inductance L2 in the circuit is connected to the 3.3V DC voltage VCC3.3, the other end of the inductance L2 is connected to the 9th pin of the microcontroller U5, and the analog power supply voltage signal AVCC is drawn out, and one end of the capacitor C13 is connected to the polar capacitor E6 The positive pole of the capacitor is connected to the other end of the inductor L2 at the same time, the other end of the capacitor C13 and the negative pole of the polarized capacitor E6 are connected to the 8th pin of the microcontroller U5, and the 0 ohm resistor R21 is a single point for digital ground and analog ground Connect a resistor, one end of which is connected to the 8th pin of the microcontroller U5, and the other end is connected to the digital ground; in the front-end signal conditioning circuit 2, the positive voltage followers of the voltage followers U2A, U2C and U2D in the four-channel high-precision operational amplifier The power connection terminals are all connected to the analog power supply voltage signal AVCC drawn from the main control CPU1, wherein a capacitor C2 is also connected between the positive power connection terminal of the voltage follower U2A and the analog ground, and the negative terminals of the voltage followers U2A, U2C and U2D The power connection terminals are all connected to the analog ground, the voltage follower U2D and resistors R6 and R9 form a 1.65V voltage reference generating circuit, and one end of the resistor R6 is connected to one end of the resistor R9, and then connected to the inverting input terminal of the voltage follower U2D , the other end of the resistor R6 is connected to the analog power supply voltage signal AVCC, the other end of the resistor R9 is connected to the analog ground, the output end of the voltage follower U2D is connected to its non-inverting input end, and the 1.65V voltage reference signal REF is drawn out, and the AC current sampling input terminal P1 is connected to both ends of the enameled wire output wire wound on the iron core of the clamp meter, the first pin of the AC current sampling input terminal P1 is connected to one end of the resistor R3, and the second pin of the AC current sampling input terminal P1 is connected to the other end of the resistor R3 And one end of the resistor R4, the other end of the resistor R4 is connected to the 1.65V voltage reference signal REF, after the positive pole of the clamping diode D1 is connected to the negative pole of the clamping diode D3 and one end of the resistor R3 , and then connected to the non-inverting input terminal of the voltage follower U2A, the negative pole of the clamping diode D1 is connected to the analog power supply voltage signal AVCC, the positive pole of the clamping diode D3 is connected to the analog ground, and the output terminal of the voltage follower U2A is connected to its inverting input terminal , and connect one end of the resistor R1 at the same time, the other end of the resistor R1 is connected to one end of the capacitor C1, the other end of the capacitor C1 is connected to the analog ground, the AC voltage input terminal P2 is connected to the AC 0-400V power supply, the first and the first terminals of the AC voltage input terminal P2 The second pin is connected to one end of resistor R5 and resistor R10 respectively, the other end of resistor R5 and resistor R10 are respectively connected to both ends of resistor R8, one end of resistor R12 is connected to one end of resistor R10, and the other end of resistor R12 is connected to 1.65V voltage reference Signal REF, the anode of the clamping diode D4 is connected to the negative terminal of the clamping diode D5 and the other end of the resistor R10, and then connected to the non-inverting input terminal of the voltage follower U2C, and the negative terminal of the clamping diode D4 is connected to the analog power supply voltage signal AVCC , the anode of the clamping diode D5 is connected to the analog ground, the output terminal of the voltage follower U2C is connected to its inverting input terminal, and one end of the resistor R7 is connected at the same time, the other end of the resistor R7 is connected to one end of the capacitor C3, and the other end of the capacitor C3 Connect to the analog ground; between the front-end signal conditioning circuit 2 and the main control CPU1, the other end of the resistor R1 is connected to the 12th pin of the microcontroller U5, and the other end of the resistor R7 is connected to the 13th pin of the microcontroller U5; In the keyboard circuit 3, the 1st, 2nd, 4th and 5th terminals of the control key KEY1 are short-circuited with each other, and the 3rd and 6th terminals of the control key KEY1 are short-circuited and connected to one end of the resistor R11, and the other end of the resistor R11 Connect the 3.3V DC voltage VCC3.3, and connect one end of the resistor R13 at the same time, the other end of the resistor R13 is connected to the second and third terminals of the control button KEY2, and the first and fourth terminals of the control button KEY2 are short-circuited; the keyboard circuit 3 and the main control CPU1, the fifth terminal of the control button KEY1 is connected to the 32nd pin of the microcontroller U5, and the first terminal of the control button KEY2 is connected to the 33rd pin of the microcontroller U5; in the voice circuit 4 Inside, the 6th pin of the audio power amplifier chip U3 is connected to the 3.3V DC voltage VCC3.3, and at the same time connected to the positive pole of the polarized capacitor E3, and the negative pole of the polarized capacitor E3 is connected to the 7th pin of the audio power amplifier chip U3, The first pin of the audio power amplifier chip U3 is connected to one end of the capacitor C4, the other end of the capacitor C4 is connected to the negative pole of the polarized capacitor E4, and connected to the digital ground, and the positive pole of the polarized capacitor E4 is connected to the first pin of the audio power amplifier chip U3 2 and 3 pins are connected, the 4th pin of the audio power amplifier chip U3 is connected to one end of the resistor R14 and the resistor R15, the other end of the resistor R14 is connected to one end of the capacitor C5, and the other end of the resistor R15 is connected to the audio power amplifier chip U3. The 5th pin, the two ends of the speaker SP1 are connected to the 5th and 8th pins of the audio power amplifier chip U3; between the voice circuit 4 and the main control CPU1, the capacitor C5 The other end is connected to the 14th pin of the microcontroller U5, and the 1st pin of the audio power amplifier chip U3 is connected to the 15th pin of the microcontroller U5; in the power supply circuit 5, the 1st pin of the switching voltage regulator U1 Connect the first terminal of the DIP switch S1, and connect the positive pole of the polarized capacitor E2 at the same time, connect the negative pole of the polarized capacitor E2 to the negative pole of the battery BT1, and connect the third and fifth pins of the switching voltage regulator U1 at the same time , the third pin of the switching voltage regulator U1 is connected to the digital ground, the positive pole of the battery BT1 is connected to the second terminal of the dial switch S1, the second pin of the switching voltage regulator U1 is connected to the negative pole of the diode D2 and one end of the inductor L1, The anode of the diode D2 is connected to the digital ground, and at the same time connected to the negative pole of the polarized capacitor E1, the positive pole of the polarized capacitor E1 is connected to the other end of the inductor L1, and the other end of the inductor L1 generates a 3.3V DC voltage VCC3.3, and is connected to After the 4th pin of the switching voltage regulator U1 and the 5th and 7th terminals of the code switch S1 are short-circuited, one end of the resistor R2 is connected, and the other end of the resistor R2 is connected with the other end of the inductor L1; the power supply circuit 5 and Between the main control CPU1, the 6th and 8th terminals of the dial switch S1 are respectively connected to the 42nd and 43rd pins of the microcontroller U5; in the LCD liquid crystal interface circuit 6, the 8th pin of the LCD driver U4 is connected to One end of resistor R16, the other end of resistor R16 is connected to 3.3V DC voltage VCC3.3, and at the same time connected to the 9th pin of LCD driver U4 and one end of capacitor C6, the other end of capacitor C6 is connected to digital ground, 4-digit 7-segment digital The 1st to 4th pins of the LCD liquid crystal screen DS1 are respectively connected to the 16th to 13th pins of the LCD driver U4, and the 5th to 13th pins of the 4-digit 7-segment digital LCD liquid crystal screen DS1 are respectively connected to the 48th pins of the LCD driver U4. ～40 pins are connected; between the LCD liquid crystal interface circuit 6 and the main control CPU1, the 1st～4 pins of the LCD driver U4 are respectively connected with the 4th, 3rd, 2nd and 46th pins of the microcontroller U5 connect.

As shown in FIG. 6, in the power supply circuit 5, the battery BT1 is a 9V alkaline battery. In the power supply circuit 5, the dial switch S1 is a dial dial switch.

As shown in Figure 7, between the LCD liquid crystal interface circuit 6 and the main control CPU1, the 1st to 4th pins of the LCD driver U4 are respectively connected to the 4th, 3rd, 2nd and 46th pins of the microcontroller U5 through the SPI communication interface. pins are connected.

The meter is a fast steal detection instrument, and its host and clamp meter are integrated into one. Insert the live wire in, neutral out and live wire out of the electric energy meter respectively into the clamp head of the clamp meter to measure the live wire incoming current, neutral wire outgoing current and live wire outgoing current of the electric energy meter circuit, and connect the voltage wire of the electric energy meter to The input voltage of the electric energy meter can be measured by connecting to the voltage input terminal of the burglar detector; After the voltage and current analog signals are conditioned by the front-end signal conditioning circuit 2 on the internal working circuit board of the anti-theft detector, they are directly input into the microcontroller U5 of the main control CPU1, and the instantaneous voltage is obtained after the internal AD conversion of the microcontroller U5 , current sampling value, the sampling value is calculated by the microcontroller U5 to obtain electrical parameters such as voltage and current, and various electrical parameters are sent to the LCD liquid crystal interface circuit 6 for display. If you want to keep the electrical parameter content displayed by the LCD liquid crystal interface circuit 6 To not refresh, you can press the control key KEY1 in the keyboard circuit 3 once.

The calculation principle of the electrical parameters of the meter fast detector is as follows:

1. Voltage calculation formula

In the formula, Ua and uak are voltage effective value and instantaneous value respectively, and N is the number of AC sampling points per cycle;

2. Current calculation formula

In the formula, Ia and iak are the effective value and instantaneous value of the current respectively, and N is the number of AC sampling points per cycle.

The principle of using this electric meter fast detection instrument to judge whether the electric energy meter is normal, whether there is electricity stealing or not is as follows: first, insert the live wire of the electric energy meter into the clamp head of the clamp meter, and press the control button in the keyboard circuit 3 KEY2, measure the current Ia of the live wire of the electric energy meter circuit, and display the current value through the LCD liquid crystal interface circuit 6; then, change the line clamped in the clamp head, and clamp the zero line outgoing line of the electric energy meter into the clamp meter Inside the pliers, press the control button KEY2 in the keyboard circuit 3 again to measure the zero line outgoing current Ib of the electric energy meter circuit, and display this current value through the LCD liquid crystal interface circuit 6; The internal calculation process of the line outgoing current Ib is to input the live wire incoming current analog signal or the zero line outgoing current analog signal in the anti-theft instrument, after being conditioned by the front-end signal conditioning circuit 2 on the internal working circuit board of the anti-theft instrument, directly input Into the micro-controller U5 of the main control CPU1, after the internal AD conversion of the micro-controller U5, the instantaneous current sampling value of the live wire entering the line or the neutral line exiting the line is obtained, and the instantaneous current sampling value of the live line entering the line or the neutral line exiting the line is controlled U5 calculates the RMS current value of the incoming live wire or the outgoing wire of the neutral wire, that is, the incoming current Ia of the live wire or the outgoing current Ib of the neutral wire; after both the incoming current Ia of the live wire and the outgoing current Ib of the neutral wire are measured, then The instrument judges according to the following judgment basis, and the voice circuit 4 provides corresponding beautiful human voice voice prompts according to the judgment result. The judgment basis is as follows: when (Ia / Ib -1) > 15%, prompt "neutral line may be disconnected", when (Ia / Ib -1) < 15%, prompt "outside line access", Moreover, both of the above two situations indicate that the state of the electric energy meter is abnormal, and there may be electricity theft.

In addition, by measuring the input voltage of the watt-hour meter through this meter fast detector, it can be judged whether the voltage quality of the power supply line is good, whether the voltage is too high or too low, and whether it is within the allowable fluctuation range.

Claims (4)

1. a kind of ammeter rapid stealing detecting instrument, including host shell, split-core type meter and operating circuit plate, described host shell is provided with liquid Crystalline substance screen observation window, described split-core type meter is made up of binding clip housing and iron core, and described operating circuit plate is arranged in host shell, its It is characterized in that：Master cpu is included on described operating circuit plate（1）, analog signal processing（2）, keyboard circuit（3）, language Sound circuit（4）, power circuit（5）With LCD liquid crystal interface circuits（6）, master cpu（1）Inside there are microcontroller U5, external clock electricity Road, pull down resistor R17, CPU electrification reset circuit, cpu power VCC decoupling capacitances, polarized electric capacity E5, AD interface analog power Filter circuit and 0 Europe resistance R21, wherein, model STM32F100CBT6 of microcontroller U5 has 8M in outer clock circuit There is resistance R18 and electric capacity C9 in crystal oscillator Y1 and electric capacity C7 and C8, CPU electrification reset circuit, in cpu power VCC decoupling capacitances There are electric capacity C10, C11 and C12, there is inductance L2, electric capacity C13 and polarized electric capacity E6 in AD interface analog power filter circuits；Before End signal modulate circuit（2）Inside there is voltage follower U2A, U2C and U2D, the alternating current in four-way high precision operating amplifier Stream sampling input terminal P1, the sub- P2 of ac voltage input, resistance R1, R3～R10 and R12, electric capacity C1～C3 and clamper two Pole pipe D1 and D3～D5, model SGM8554 of its four-way high precision operating amplifier, clamp diode D1's and D3～D5 Model is IN4148；Keyboard circuit（3）Inside there are control button KEY1 and KEY2 and resistance R11 and R13；Sound circuit（4） Inside there are audio frequency power amplifier chip U3, polarized electric capacity E3 and E4, electric capacity C4 and C5, resistance R14 and R15 and loudspeaker SP1, its audio frequency Model SGM4890YMS of power amplifier chips U3；Power circuit（5）Inside there are battery BT1, regulator U1, polarized electricity Hold E1 and E2, diode D2, inductance L1, resistance R2 and toggle switch S1, the model of its regulator U1 LM2596S-3.3, model STPS2L25U of diode D2, model DO3316P-104 of inductance L1, toggle switch S1's Model SW DIP-6；LCD liquid crystal interface circuits（6）Inside there are lcd driver U4, resistance R16, electric capacity C6 and 47 segment numerals LCD liquid crystal display DS1, model HT1621B of its lcd driver U4, the model of 47 segment numeral LCD liquid crystal display DS1 GDC8310；

Its annexation is：In master cpu（1）Interior, the 1st pin of microcontroller U5 connects by power circuit（5）Produce The mutual short circuit of the pin of 23rd, the 35th and the 47th of 3.3V DC voltage VCC3.3, microcontroller U5 is followed by digitally, external clock The two ends of circuit crystal oscillator Y1 are connected respectively to the 5th and the 6th pin of microcontroller U5, and the one of pull down resistor R17 terminates digitally, Its other end is connected to the 44th pin of microcontroller U5, and one end of resistance R18 and electric capacity C9 connects in CPU electrification reset circuits It is connected to the 7th pin of microcontroller U5, the other end connection 3.3V DC voltage VCC3.3 of resistance R18, the other end of electric capacity C9 Connect digitally, one end of electric capacity C10, C11 and C12 is connected respectively to the of microcontroller U5 in cpu power VCC decoupling capacitances 24th, the 36th and the 48th pin, its other end connects digitally, the positive pole connection 3.3V DC voltages of polarized electric capacity E5 VCC3.3, and while be connected with the pin of the 24th, the 36th and the 48th of microcontroller U5, the negative pole of polarized electric capacity E5 connects numeral Ground, one end connection 3.3V DC voltage VCC3.3 of AD interface analog power filter circuit internal inductances L2, the other end of inductance L2 The 9th pin of microcontroller U5 is connected to, and draws analog power voltage signal AVCC, one end connection polarized of electric capacity C13 The positive pole of electric capacity E6, and while connect the other end of inductance L2, the other end of electric capacity C13 and the negative pole of polarized electric capacity E6 connect The 8th pin of microcontroller U5 is connected to, 0 Europe resistance R21 is digitally to connect resistance with simulation ground single-point, and its one end is connected to micro- 8th pin of controller U5, its another termination is digitally；In analog signal processing（2）Interior, four-way high-accuracy arithmetic is put The positive electricity source connection of voltage follower U2A, U2C and U2D in big device is all connected with by master cpu（1）The simulation electricity of interior extraction Source voltage signal AVCC, wherein, electric capacity C2 is also associated between the positive electricity source connection and simulation ground of voltage follower U2A, electricity The negative electricity source connection of pressure follower U2A, U2C and U2D connects simulation ground, and voltage follower U2D and resistance R6 and R9 are constituted 1.65V voltage references produce circuit, after one end of resistance R6 is connected with one end of resistance R9, are connected to voltage follower The inverting input of U2D, the other end connection simulation power supply voltage signal AVCC of resistance R6, another termination simulation of resistance R9 Ground, the output end of voltage follower U2D is connected with its in-phase input end, and draws 1.65V voltage reference signal REF, exchange Current sample input terminal P1 connections are wound on the two ends of enamel-covered wire output line on split-core type meter iron core, alternating current sampling input terminal P1 The 1st pin connect resistance R3 one end, alternating current sampling input terminal P1 the 2nd pin connection resistance R3 the other end with And one end of resistance R4, the other end connection 1.65V voltage reference signal REF of resistance R4, positive pole and the pincers of clamp diode D1 After the position negative pole of diode D3 and one end of resistance R3 are connected, the in-phase input end of voltage follower U2A is connected to, is clamped The negative pole connection simulation power supply voltage signal AVCC of position diode D1, the positive pole of clamp diode D3 connects simulation ground, voltage follow The output end of device U2A is connected with its inverting input, and while connects one end of resistance R1, the other end connection of resistance R1 is electric Hold one end of C1, another termination simulation ground of electric capacity C1, the sub- P2 connections exchange 0～400V power supplys of ac voltage input, exchange 1st and the 2nd pin of voltage input-terminal P2 connects respectively one end of resistance R5 and resistance R10, and resistance R5's and resistance R10 is another One end connects respectively the two ends of resistance R8, and one end of resistance R12 connects one end of resistance R10, the other end connection of resistance R12 The positive pole of 1.65V voltage reference signal REF, clamp diode D4 and the negative pole of clamp diode D5 and resistance R10's is another After end is connected, the in-phase input end of voltage follower U2C, the negative pole connection analog power electricity of clamp diode D4 are connected to The positive pole of pressure signal AVCC, clamp diode D5 connects simulation ground, and the output end of voltage follower U2C is connected with its inverting input Connect, and while connect one end of resistance R7, the other end of resistance R7 connects one end of electric capacity C3, another termination simulation of electric capacity C3 Ground；Analog signal processing（2）With master cpu（1）Between, the other end of resistance R1 is connected to the 12nd of microcontroller U5 and draws Pin, the other end of resistance R7 is connected to the 13rd pin of microcontroller U5；In keyboard circuit（3）It is interior, the of control button KEY1 1st, the mutual short circuit of the terminal of the 2nd, the 4th and the 5th, connects one end of resistance R11 after the 3rd and the 6th terminal short circuit of control button KEY1, The other end connection 3.3V DC voltage VCC3.3 of resistance R11, and while connect one end of resistance R13, the other end of resistance R13 2nd and the 3rd terminal of connection control button KEY2, the 1st and the 4th terminal phase short circuit of control button KEY2；Keyboard circuit（3）With Master cpu（1）Between, the 5th terminal of control button KEY1 is connected to the 32nd pin of microcontroller U5, control button KEY2 1st terminal is connected to the 33rd pin of microcontroller U5；In sound circuit（4）It is interior, the 6th pin connection of audio frequency power amplifier chip U3 3.3V DC voltage VCC3.3, and while the positive pole of polar capacitor E3 is connected with, the negative pole of polarized electric capacity E3 is connected to audio frequency 7th pin of power amplifier chips U3, the 1st pin of audio frequency power amplifier chip U3 connects one end of electric capacity C4, the other end of electric capacity C4 with The negative pole of polarized electric capacity E4 is connected, and connects digitally, the positive pole of polarized electric capacity E4 and the 2nd of audio frequency power amplifier chip U3 and 3rd pin is connected, and the 4th pin of audio frequency power amplifier chip U3 connects one end of resistance R14 and resistance R15, and resistance R14's is another One end of end connection electric capacity C5, the other end of resistance R15 is connected to the 5th pin of audio frequency power amplifier chip U3, the two ends of loudspeaker SP1 It is connected to the 5th and the 8th pin of audio frequency power amplifier chip U3；Sound circuit（4）With master cpu（1）Between, the other end of electric capacity C5 The 14th pin of microcontroller U5 is connected to, the 1st pin of audio frequency power amplifier chip U3 connects the 15th pin of microcontroller U5； Power circuit（5）Interior, the 1st pin of regulator U1 connects the 1st terminal of toggle switch S1, and while is connected with pole Property electric capacity E2 positive pole, the negative pole of polarized electric capacity E2 connects the negative pole of battery BT1, and while connecting valve voltage regulator U1 The the 3rd and the 5th pin, the 3rd pin of regulator U1 connects digitally, the positive pole connection toggle switch S1 of battery BT1 The 2nd terminal, regulator U1 the 2nd pin connection diode D2 negative pole and inductance L1 one end, diode D2 Positive pole connect digitally, and while be connected with the negative pole of polar capacitor E1, the positive pole connection inductance L1's of polarized electric capacity E1 is another One end, the other end of inductance L1 produces 3.3V DC voltage VCC3.3, while the be connected to regulator U1 the 4th draws Pin, after the 5th and the 7th terminal short circuit of toggle switch S1, connects one end of resistance R2, and the other end of resistance R2 is another with inductance L1 One end is connected；Power circuit（5）With master cpu（1）Between, the 6th and the 8th terminal of toggle switch S1 is connected respectively to micro-control 42nd and the 43rd pin of device U5 processed；In LCD liquid crystal interface circuits（6）It is interior, the 8th pin connection resistance R16 of lcd driver U4 One end, resistance R16 the other end connection 3.3V DC voltage VCC3.3, and while connect lcd driver U4 the 9th pin and One end of electric capacity C6, another termination of electric capacity C6 digitally, the 1st～4 pin of 47 segment numeral LCD liquid crystal display DS1 respectively with 16th～13 pin of lcd driver U4 is connected, the 5th～13 pin of 47 segment numeral LCD liquid crystal display DS1 respectively with LCD 48th～40 pin of driver U4 is connected；LCD liquid crystal interface circuits（6）With master cpu（1）Between, lcd driver U4's 1st～4 pin is connected respectively with the pin of the 4th, the 3rd, the 2nd and the 46th of microcontroller U5；

Stealing detecting instrument measurement live wire line current Ia or zero line go out the internal arithmetic process of line current Ib：In input stealing detecting instrument Live wire line current analog signal or zero line outlet current analog signal, the front end letter on stealing detecting instrument internal pull-up circuit plate Number modulate circuit（2）After conditioning, it is directly inputted in the microcontroller U5 of master cpu 1, Jing microcontrollers U5 inside AD conversion Afterwards, the transient current sampled value that live wire enters line or zero line outlet is obtained, live wire enters the transient current sampled value of line or zero line outlet The current effective value that live wire enters line or zero line outlet is calculated through microcontroller U5, that is, measures live wire line current Ia or zero Line goes out line current Ib；Live wire line current Ia and zero line go out the equal side of line current Ib measure come after, stealing detecting instrument according to it is following judge according to According to being judged, sound circuit（4）Corresponding beautiful voice prompting is provided according to judged result；Described basis for estimation For：As Ia/Ib -1>When 15%, point out " zero line may disconnect ", as Ia/Ib -1<When 15%, point out " have outside line to connect Enter ", and both the above situation, show that electric energy table status are abnormal, there may be electricity filching behavior.

2. ammeter rapid stealing detecting instrument according to claim 1, is characterized in that：In power circuit（5）Interior, battery BT1 is 9V Alkaline battery.

3. ammeter rapid stealing detecting instrument according to claim 1 and 2, is characterized in that：In power circuit（5）It is interior, toggle switch S1 is rotating disk toggle switch.

4. ammeter rapid stealing detecting instrument according to claim 3, is characterized in that：LCD liquid crystal interface circuits（6）With master cpu （1）Between, the 1st～4 pin of lcd driver U4 by SPI communication interfaces respectively with microcontroller U5 the 4th, the 3rd, the 2nd and 46th pin is connected.