CN118658254A - An electrical fire monitoring device - Google Patents

Abstract

The present invention relates to the field of electrical fire monitoring technology, and in particular to an electrical fire monitoring device; comprising a power conversion circuit, a residual current collection module, a smoke sensor module, a main control chip, an RS485 communication module, a 4G communication module, a three-phase voltage monitoring module, a three-phase line temperature measurement module and a three-phase current measurement module; the main control chip is electrically connected to the RS485 communication module, the residual current collection module, the power conversion circuit, the three-phase voltage monitoring module, the three-phase line temperature measurement module, the three-phase current measurement module and the smoke sensor module, and the main control chip is connected to the 4G communication module through a wireless signal; the residual current collection module, the three-phase voltage monitoring module and the three-phase current measurement module are electrically connected to an external three-phase system respectively. By adding voltage monitoring, current monitoring and three-phase line temperature measurement functions, all-round monitoring can be performed, and by adding RS485 communication and 4G communication, the electrical environment can be monitored in real time to improve safety.

Description

An electrical fire monitoring device

Technical Field

The invention relates to the technical field of electrical fire monitoring, and in particular to an electrical fire monitoring device.

Background Art

Fire is a major disaster with a high probability of occurrence, which seriously threatens human life and safety, brings about significant property losses, and causes great environmental pollution. There are many factors that induce fire accidents, among which electrical fires caused by improper use of electrical equipment, corrosion and aging of electrical lines and fault factors account for 50% of the total number of fires.

In order to monitor electrical fires, electrical fire monitoring and alarm devices have emerged. At present, when monitoring electrical fires, only one location is monitored, which cannot meet the current monitoring requirements for high safety.

Since the common electrical fire monitoring systems on the market all adopt a single monitoring method, namely, one of temperature monitoring, short circuit monitoring and residual current monitoring, it is impossible to achieve comprehensive monitoring of electrical fires that may be caused by various possible factors such as short circuit, overcurrent or leakage.

Summary of the invention

In order to overcome the defects of the prior art, the technical problem to be solved by the present invention is to provide an electrical fire monitoring device that can perform all-round monitoring. In order to solve the above technical problems, the technical solution adopted by the present invention is:

An electrical fire monitoring device, comprising a power conversion circuit, a residual current collection module and a smoke sensing module, a main control chip, an RS485 communication module, a 4G communication module, a three-phase voltage monitoring module, a three-phase line temperature measurement module and a three-phase current measurement module;

The main control chip is electrically connected to the RS485 communication module, the residual current collection module, the power conversion circuit, the three-phase voltage monitoring module, the three-phase line temperature measurement module, the three-phase current measurement module and the smoke sensor module respectively, and the main control chip is connected to the 4G communication module via a wireless signal;

The residual current collection module, the three-phase voltage monitoring module and the three-phase current measurement module are electrically connected to an external three-phase system respectively.

The beneficial effects of the present invention are as follows: on the traditional basis, voltage monitoring, current monitoring and three-phase line temperature measurement functions are added, electrical fires can be monitored in an all-round way, meeting the current monitoring requirements for high safety, and RS485 communication function is added to interact with background data, so that real-time monitoring data can be viewed through the local background, and 4G communication function is added to interact with cloud platform data, so that real-time monitoring data can be viewed through the background, so that the electrical environment can be monitored in real time, thereby improving safety.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a system block diagram of an electrical fire monitoring device;

FIG2 is a circuit connection diagram of the main control chip;

FIG3 shows a circuit connection diagram of a three-phase voltage monitoring module;

FIG4 shows a circuit connection diagram of a three-phase current monitoring module;

FIG5 is a circuit connection diagram of a three-phase line temperature measurement module;

Figure 6 shows the circuit connection diagram of the RS485 communication module;

FIG7 shows a circuit connection diagram of a smoke sensor module;

FIG8 shows a circuit connection diagram of a residual current collection module;

FIG9 is a circuit connection diagram of a power conversion module;

FIG10 shows a circuit connection diagram of a 4G communication module;

FIG11 is a circuit connection diagram of a 4G communication module;

FIG12 shows a circuit connection diagram of a 4G communication module;

FIG13 is a circuit connection diagram of a 4G communication module;

FIG14 shows a circuit connection diagram of a 4G communication module;

Description of labels:

1. Main control chip; 2. Three-phase voltage monitoring module; 3. Three-phase current monitoring module;

4. Residual current collection module; 5. Three-phase line temperature measurement module; 6. Smoke sensor module;

7. Power conversion module; 8. RS485 communication module; 9. 4G communication module.

DETAILED DESCRIPTION

In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following is an explanation in combination with the implementation modes and the accompanying drawings.

As shown in FIGS. 1 to 14 , an electrical fire monitoring device of the present invention includes a power conversion circuit, a residual current collection module and a smoke sensing module, a main control chip, an RS485 communication module, a 4G communication module, a three-phase voltage monitoring module, a three-phase line temperature measurement module and a three-phase current measurement module;

The main control chip is electrically connected to the RS485 communication module, the residual current collection module, the power conversion circuit, the three-phase voltage monitoring module, the three-phase line temperature measurement module, the three-phase current measurement module and the smoke sensor module respectively, and the main control chip is connected to the 4G communication module via a wireless signal;

The residual current collection module, the three-phase voltage monitoring module and the three-phase current measurement module are electrically connected to an external three-phase system respectively.

From the above description, it can be seen that the beneficial effects of the present invention are: adding voltage monitoring, adding current monitoring, adding three-phase line temperature measurement function, and being able to conduct all-round monitoring of the occurrence of electrical fires, meeting the current monitoring requirements for high safety, adding RS485 communication function, and connecting with background data. Real-time monitoring data can be viewed through the local background, plus 4G communication function, connected with cloud platform data, real-time monitoring data can be viewed through the background, and the electrical environment can be monitored in real time to improve safety.

Further, the three-phase voltage monitoring module includes an A-phase voltage monitoring circuit, a B-phase voltage monitoring circuit and a C-phase voltage monitoring circuit;

The A-phase voltage monitoring circuit includes a resistor R26, a resistor R28, a resistor R29 and a capacitor C24; one end of the resistor R28 is electrically connected to one end of the resistor R26, the other end of the resistor R28 is electrically connected to the resistor R29, the other end of the resistor R26 is electrically connected to the other end of the resistor R29, the capacitor C24 is connected in parallel with the resistor R29, and one end after the connection is electrically connected to the main control chip; the two ends of the resistor R28 are the two ends of the A-phase monitoring circuit, and are electrically connected to the A-phase line and the N line in the three-phase system;

The B-phase voltage monitoring circuit includes a resistor R32, a resistor R33, a resistor R34 and a capacitor C25; one end of the resistor R32 is electrically connected to one end of the resistor R33, the other end of the resistor R33 is electrically connected to the resistor R34, the other end of the resistor R32 is electrically connected to the other end of the resistor R34, the capacitor C25 is connected in parallel with the resistor R34, and one end after the connection is electrically connected to the main control chip; the two ends of the resistor R33 are the two ends of the B-phase monitoring circuit, and are electrically connected to the B-phase line and the N line in the three-phase system;

The C-phase voltage monitoring circuit includes resistor R38, resistor R39, resistor R40 and capacitor C30; one end of the resistor R38 is electrically connected to one end of the resistor R39, the other end of the resistor R39 is electrically connected to the resistor R40, the other end of the resistor R38 is electrically connected to the other end of the resistor R40, the capacitor C30 is connected in parallel with the resistor R40, and the connected end is electrically connected to the main control chip; the two ends of the resistor R39 are the two ends of the B-phase monitoring circuit, and are electrically connected to the C-phase line and the N line in the three-phase system.

The three-phase voltage monitoring module also includes a resistor R30, a resistor R35 and a resistor R36;

One end of the resistor R30 is electrically connected to one end of the resistor R26, and the other end of the resistor R30 is electrically connected to one end of the resistor R32;

One end of the resistor R35 is electrically connected to one end of the resistor R32, and the other end of the resistor R35 is electrically connected to one end of the resistor R38;

One end of the resistor R36 is electrically connected to one end of the resistor R26 , and the other end of the resistor R36 is electrically connected to one end of the resistor R38 .

From the above description, we can know that the function of this module is to monitor the three-phase voltage value in the three-phase system. R28, R33, and R39 are respectively the withstand voltage protection of A to N, B to N, and C to N, to prevent lightning strikes from breaking through the main control chip U4; R30, R35, and R36 are respectively the withstand voltage protection of A to B, B to C, and A to C, to prevent excessive voltage difference between lines from breaking through the main control chip U4.

Further, the three-phase current measurement module includes an A-phase current monitoring circuit, a B-phase current monitoring circuit and a C-phase current monitoring circuit;

The A-phase current monitoring circuit includes a current transformer U2, a resistor R1, a resistor R2, a resistor R4, a resistor R5, a capacitor C1 and a capacitor C5;

The I+ pin of the current transformer U2 is electrically connected to one end of the resistor R1 and one end of the resistor R2 respectively, the other end of the resistor R1 is grounded, the other end of the resistor R2 is electrically connected to one end of the capacitor C1, the other end of the capacitor C1 is grounded, and the other end of the resistor R2 is electrically connected to the main control chip;

The P1 pin and the P2 pin of the current transformer U2 are electrically connected to the A-phase primary cable;

The B-phase current monitoring circuit includes a current transformer U5, a resistor R9, a resistor R10, a resistor R14, a resistor R16, a capacitor C6 and a capacitor C9;

The I-pin of the current transformer U5 is electrically connected to one end of the resistor R16 and one end of the resistor R14 respectively, the other end of the resistor R16 is grounded, the other end of the resistor R14 is electrically connected to one end of the capacitor C9, the other end of the capacitor C9 is grounded, and the other end of the resistor R14 is electrically connected to the main control chip;

The P1 pin and the P2 pin of the current transformer U5 are electrically connected to the B-phase primary cable respectively;

The C-phase current monitoring circuit includes a current transformer U10, a resistor R18, a resistor R19, a resistor R20, a resistor R21, a capacitor C12 and a capacitor C17;

The I+ pin of the current transformer U10 is electrically connected to one end of the resistor R18 and one end of the resistor R19 respectively, the other end of the resistor R18 is grounded, the other end of the resistor R19 is electrically connected to one end of the capacitor C12, the other end of the capacitor C12 is grounded, and the other end of the resistor R19 is electrically connected to the main control chip;

The P1 pin and the P2 pin of the current transformer U10 are electrically connected to the C-phase primary cable.

From the above description, it can be seen that the function of this module is to monitor the current value of the cable in the distribution box. Here, phase A monitoring is taken as an example (the same applies to phases B and C). U2 is an open-type current transformer, which can convert the current on the primary cable side into a secondary proportional current through a transformation ratio. R1 and R5 are boost resistors to ground, which can convert the secondary current converted by U2 into a voltage output. R2 and R4 are current limiting resistors to prevent the voltage after the current transformer conversion from being too high and breaking through the IO port of the MCU; C1 and C5 are filter capacitors, which filter the converted voltage more smoothly to ensure the accuracy of the data when the MCU performs ADC sampling.

Further, the three-phase line temperature measurement module includes an A-phase temperature measurement circuit, a B-phase temperature measurement circuit and a C-phase temperature measurement circuit;

The A-phase temperature measurement circuit includes a thermistor R46, a resistor R50 and a capacitor C36, one end of the resistor R50 is electrically connected to one end of the resistor R46 and one end of the capacitor C36 respectively, the other end of the capacitor C36 is grounded, the other end of the resistor R50 is grounded, and the other end of the resistor R36 is electrically connected to a 3.3V power supply of an external device; one end of the resistor R50 is electrically connected to the main control chip;

The B-phase temperature measurement circuit includes a thermistor R47, a resistor R51 and a capacitor C37, one end of the resistor R51 is electrically connected to one end of the resistor R47 and one end of the capacitor C36 respectively, the other end of the capacitor C37 is grounded, the other end of the resistor R51 is grounded, and the other end of the resistor R37 is electrically connected to a 3.3V power supply of an external device; one end of the resistor R51 is electrically connected to the main control chip;

The C-phase temperature measurement circuit includes a thermistor R48, a resistor R52 and a capacitor C38, one end of the resistor R52 is electrically connected to one end of the resistor R48 and one end of the capacitor C38 respectively, the other end of the capacitor C38 is grounded, the other end of the resistor R52 is grounded, and the other end of the resistor R36 is electrically connected to the 3.3V power supply of the peripheral device; one end of the resistor R52 is electrically connected to the main control chip.

From the above description, we can know that the function of this module is to monitor the temperature change of the three-phase line to prevent the temperature from being too high when short circuit or overload occurs. Here we take the temperature monitoring of phase A as an example (the same applies to phase B and C), where R46 is an NTC thermistor, which is pasted on the phase A line to measure the temperature change of phase A. R46 and R50 form a voltage divider circuit, where C36 is a filter capacitor to ensure the output voltage V waveform is stable.

Further, the RS485 communication module includes a communication chip U10, a resistor R43, a resistor R44, a resistor R45, a single-phase suppression diode D6, a single-phase suppression diode D7 and a capacitor C31;

The eighth pin of the communication chip U10 is electrically connected to one end of the capacitor C31, and the other end of the capacitor C31 is grounded;

The seventh pin of the communication chip U10 is electrically connected to one end of the resistor R43, the sixth pin of the communication chip U10 is electrically connected to one end of the resistor R45, and both ends of the resistor R44 are electrically connected to the other end of the resistor R43 and the other end of the resistor R45 respectively;

The anode of the single-phase suppression diode D6 is grounded, and the cathode of the single-phase suppression diode D6 is electrically connected to the sixth pin of the communication chip U10. The anode of the single-phase suppression diode D7 is grounded, and the cathode of the single-phase suppression diode D7 is electrically connected to the seventh pin of the communication chip U10.

From the above description, it can be seen that the function of this module is to communicate data processed by MCU with the outside through RS485 communication. Among them, U10 is the RS485 communication chip, R43 and R45 are current limiting resistors to prevent overcurrent from breaking down U10 during external signal transmission, and D6 and D7 are single-phase suppression diodes of A and B, respectively, to protect A and B. R44 is the matching resistor between AB, in order to match the impedance when communicating with external RS485. C31 is the filter capacitor of U10 to ensure a stable power supply voltage.

Furthermore, the 4G communication module includes a 4G chip U8, a synchronous rectification step-down circuit, a voltage divider circuit, a level matching circuit and an indication circuit;

The synchronous rectification and buck circuit includes a synchronous buck regulator U9, a resistor R25, a resistor R27, a resistor R31, a resistor R37, a resistor R41, a capacitor C21, a capacitor C22, a capacitor C23, a capacitor C26, a capacitor C27, a capacitor C28, a capacitor C29, an inductor L1 and a zener diode D5;

The second pin of the synchronous buck regulator U9 is electrically connected to one end of the resistor R25, and the other end of the resistor R25 is electrically connected to the external 5V power supply; the capacitor C21 is connected in parallel with the capacitor C22, and one end of the connected capacitor is electrically connected to the second pin of the synchronous buck regulator U9, and the other end of the connected capacitor is grounded; one end of the resistor R27 is electrically connected to the second pin of the synchronous buck regulator U9, and the other end of the resistor R27 is electrically connected to the seventh pin of the synchronous buck regulator U9;

The eighth pin of the synchronous buck regulator U9 is electrically connected to one end of the capacitor C26, the other end of the capacitor C26 is grounded, and the fourth pin of the synchronous buck regulator U9 is grounded;

The sixth pin of the synchronous buck regulator U9 is electrically connected to one end of the capacitor C27, the other end of the capacitor C27 is electrically connected to one end of the resistor R41, and the other end of the resistor R41 is grounded;

The first pin of the synchronous buck regulator U9 is electrically connected to one end of the capacitor C23, and the other end of the capacitor C23 is electrically connected to the third pin of the synchronous buck regulator U9;

The fifth pin of the synchronous buck regulator U9 is electrically connected to one end of the resistor R31 and one end of the resistor R37 respectively, and the other end of the resistor R37 is grounded; one end of the third pin of the synchronous buck regulator U9 is electrically connected to one end of the inductor L1, and the other end of the resistor R31 is electrically connected to the other end of the inductor L1; one end of the capacitor C28 is electrically connected to the other end of the inductor L1, and the other end of the capacitor C28 is grounded; one end of the capacitor C29 is electrically connected to the other end of the inductor L1, and the other end of the capacitor C29 is grounded; the cathode of the zener diode D5 is electrically connected to the other end of the inductor L1, and the anode of the zener diode D5 is grounded; the other end of the inductor L1 is electrically connected to the 4G chip U8;

From the above description, we can know that U9 is a synchronous buck regulator, pin 2 is the input terminal, R25 is a current limiting protection resistor to prevent overcurrent from breaking down U9; C21 and C22 are bypass capacitors to absorb noise interference at the power input terminal, and R27 is the enable terminal input, which is set to a high level to ensure that the chip is always in the startup state. C23 is a bypass capacitor, L1 is a filter inductor to remove high-frequency interference on the line, R31 and R37 form a voltage divider circuit to reduce the system voltage to the voltage required by U9, and C26, C28, and C29 are filter capacitors. C27 and R41 form a low-pass filter circuit to remove interference on the horizon. D5 is a voltage-stabilizing diode to prevent the converted voltage from being too large and breaking down U8.

Further, the level matching circuit includes a capacitor C39, a resistor R56, a resistor R57, a resistor R61, a resistor R62, a resistor R63, a resistor R64, a transistor Q3 and a transistor Q2;

The base of the transistor Q2 is electrically connected to one end of the resistor R61, the other end of the resistor R61 is electrically connected to the emitter of the transistor Q2, one end of the resistor R56 is electrically connected to the base of the transistor Q2, the other end of the resistor R56 is electrically connected to the 4G chip, one end of the resistor R62 is electrically connected to the collector of the transistor Q2, the other end of the resistor R62 is externally connected to a 3.3V power supply, and the emitter of the transistor Q2 is electrically connected to the 4G chip.

The base of the transistor Q3 is electrically connected to one end of the resistor R63, the other end of the resistor R63 is electrically connected to the collector of the transistor Q3, one end of the resistor R57 is electrically connected to the base of the transistor Q2, the other end of the resistor R57 is electrically connected to the 4G chip, one end of the capacitor C39 is electrically connected to the base of the transistor Q2, the other end of the capacitor C39 is electrically connected to the 4G chip, one end of the resistor R64 is electrically connected to the emitter of the transistor Q2, the other end of the resistor R64 is electrically connected to the 3.3V power supply of the external device, and the collector of the transistor Q2 is electrically connected to the 4G chip;

The voltage divider circuit includes a resistor R49 and a resistor R58, one end of the resistor R49 is electrically connected to one end of the resistor R58 and a 3.3V power supply of an external device, the other end of the resistor R49 is electrically connected to a 3.8V power supply of an external device, and the other end of the resistor R58 is grounded.

The indicating circuit includes a transistor Q4, a transistor Q5, a resistor R53, a resistor R54, a resistor R55, a resistor R67, a resistor R68, a resistor R69, a resistor R70, a light emitting diode D8, a light emitting diode D9 and a light emitting diode D10;

The 4G chip is electrically connected to the base of the transistor Q4 through the resistor R67, the collector of the transistor Q4 is electrically connected to the cathode of the light-emitting diode D8, the anode of the light-emitting diode D8 is electrically connected to one end of the resistor R53, the other end of R53 is electrically connected to the external 3.3V power supply, one end of the resistor R69 is electrically connected to the base of the transistor Q4, the other end of the resistor R69 is grounded, and the emitter of the transistor Q4 is grounded;

The 4G chip is electrically connected to the base of the transistor Q5 through the resistor R68, the collector of the transistor Q5 is electrically connected to the cathode of the light-emitting diode D9, the anode of the light-emitting diode D9 is electrically connected to one end of the resistor R54, the other end of R54 is electrically connected to the external 3.3V power supply, one end of the resistor R70 is electrically connected to the base of the transistor Q5, the other end of the resistor R70 is grounded, and the emitter of the transistor Q5 is grounded;

One end of the resistor R55 is electrically connected to an external 3.3V power supply, the other end of the resistor R55 is electrically connected to the positive electrode of the light emitting diode D10, and the negative electrode of the light emitting diode D10 is grounded.

Furthermore, the 4G communication module also includes a SIM card slot J1, an electrostatic diode U11, a resistor R59, a resistor R60, a resistor R65, a resistor R66, a capacitor C32, a capacitor C33, a capacitor C34 and a capacitor C35;

The 4G chip is connected to the first pin of the SIM card slot J1, the 4G chip is electrically connected to one end of the resistor R60, the other end of the resistor R60 is connected to the second pin of the SIM card slot J1, the 4G chip is electrically connected to one end of the resistor R66, the other end of the resistor R66 is connected to the second pin of the SIM card slot J1;

One end of the capacitor C33 is electrically connected to one end of the resistor R60, and the other end of the capacitor C33 is grounded; one end of the capacitor C34 is electrically connected to one end of the resistor R66, and the other end of the capacitor C34 is grounded;

One end of the capacitor C32 is connected to the first pin of the SIM card slot J1, and the other end of the capacitor C32 is grounded; the first pin of the SIM card slot J1 is electrically connected to one end of the resistor R59, the other end of the resistor R59 is electrically connected to one end of the resistor R65, the other end of the resistor R65 is electrically connected to the sixth pin of the SIM card slot J1, one end of the capacitor C35 is electrically connected to one end of the resistor R65, the other end of the capacitor is grounded, and one end of the resistor R65 is electrically connected to the 4G chip;

The first pin of the electrostatic diode U11 is electrically connected to the first pin of the SIM card slot J1, and the sixth pin of the electrostatic diode U11 is electrically connected to one end of the resistor R60; the first pin of the electrostatic diode U11 is electrically connected to one end of the resistor R66; the fourth pin of the electrostatic diode U11 is electrically connected to one end of the resistor R65.

From the above description, we can know that R60, R65, and R66 are current limiting resistors to protect the IO port between the SIM card chip and the MCU, and R59 is a pull-up resistor to improve the driving ability of J1 pin 6. C32 is a filter capacitor, U11 is a SIM card slot, C33 and C34 are bypass capacitors, and serial communication is carried out between J1 pins 2, 3, and 6 and U8.

Further, the power conversion module includes a power conversion chip U3, an LDO chip U1, a varistor R3, a capacitor C2, a capacitor C3, a capacitor C4 and a capacitor E1;

The first pin and the second pin of the power conversion chip U3 are electrically connected to the external three-phase power supply respectively; one end of the varistor R33 is electrically connected to the first pin of the power conversion chip U3, and the other end of the varistor R33 is electrically connected to the second pin of the power conversion chip U3.

From the above description, we can know that the function of this module is to power the entire system. R3 is a varistor to prevent lightning strikes, U3 is an AC to DC power module that can convert AC220V voltage into DC5V voltage, C4 and E1 are voltage output filter capacitors to ensure stable voltage output; U1 is an LDO chip that can convert DC5V voltage into DC3.3V voltage output for system use, C2 and C3 are voltage output filter capacitors to ensure stable voltage output.

The capacitor C4 and the capacitor E1 are connected in parallel, one end of the connection is electrically connected to the fourth pin of the power conversion chip U3 and the third pin of the LDO chip U1 respectively, and the other end of the connection is electrically connected to the third pin of the power conversion chip U3;

The capacitor C3 and the capacitor C2 are connected in parallel, one end of the connection is electrically connected to the second pin of the LDO chip U1, and the other end of the connection is grounded. The first pin of the LDO chip U1 is grounded.

Further, the smoke sensor module includes a smoke sensor chip U6, a transistor Q1, a resistor R6, a resistor R7, a resistor R8, a resistor R11, a resistor R12, a resistor R15, a resistor R17, a light emitting diode D1, a light emitting diode D2 and a button S1;

The first pin of the smoke detection chip U6 is electrically connected to one end of the resistor R8, the other end of the resistor R8 is electrically connected to the positive electrode of the light emitting diode D1, and the negative electrode of the light emitting diode D1 is grounded;

The second pin of the smoke detection chip U6 is electrically connected to one end of the resistor R7, the other end of the resistor R7 is electrically connected to the positive electrode of the light emitting diode D2, and the negative electrode of the light emitting diode D2 is grounded;

The third pin of the smoke detection chip U6 is electrically connected to one end of the button S1, the other end of the button S1 is electrically connected to one end of the resistor R11, and the other end of the resistor R11 is electrically connected to the external 3.3V power supply;

The twelfth pin of the smoke detection chip U6 is grounded through a resistor R12;

The fourth pin of the smoke detection chip U6 is electrically connected to the base of the transistor Q1 through the resistor R15, one end of the resistor R17 is electrically connected to the base of the transistor Q1, and the other end of the resistor R17 is grounded; one end of the resistor R6 is electrically connected to the collector of the transistor Q1, and the other end of the resistor R6 is electrically connected to the external 3.3V power supply; the collector of the transistor Q1 is electrically connected to the main control chip.

From the above description, we can know that U6 is a smoke sensor module, which can detect smoke particles in the air in real time. C8 is a filter capacitor, which ensures that the working power supply of the smoke sensor module U6 is in a stable state. R12 is a current limiting resistor, which protects the module from overcurrent. D1 and D2 are light-emitting diodes used to observe the working status of the smoke sensor module.

Furthermore, the main control chip also includes a filter circuit, a crystal oscillator circuit and a reset circuit;

The filter circuit is electrically connected to the thirty-sixth pin of the chip U4; the two ends of the crystal oscillator circuit are electrically connected to the fifth pin and the sixth pin of the chip U4 respectively; the reset circuit is electrically connected to the seventh pin of the chip U4.

From the above description, we can know that U4 is the main control MCU, which is used for the whole system program running. Among them, C13, C14, C15, and C16 are the filter capacitors of the power supply VCC to GND, which are used to protect the MCU from working stably. C7, C10, and XT1 form the crystal oscillator circuit of U4, which is used for MCU oscillation. R13 and C11 constitute the reset circuit of the U4 chip.

8 , the residual current collection module includes a current transformer U10 , a resistor R22 , a resistor R23 , a resistor R24 , a capacitor C18 , a capacitor C18 , a capacitor C18 , a diode D3 , and a diode D4 .

From the above description, it can be seen that U10 is a residual current transformer, which collects the residual current values D3 and D4 in the three-phase system to form a bidirectional diode protection tube to prevent overvoltage; R22 and R24 are current-limiting resistors between the two ends of the residual current transformer to prevent the signal voltage from being too large and breaking through the IO port of U4.

The working principle of an electrical fire monitoring device provided by the present invention is:

In this electrical fire monitoring device, the main control chip U4 is electrically connected to the residual current collection module, the three-phase voltage monitoring module, the three-phase voltage monitoring module and the three-phase line temperature measurement module; the main control chip U4 determines whether the voltage at this time is abnormal by monitoring the voltage value of each module. The main control chip is also electrically connected to the RS485 communication module and the 4G communication module to interact with the data collected by the MCU with the background.

In the residual current collection module, U10 is a residual current transformer, and its current is equal to the vector sum of phase A current + phase B current + phase C current. Assuming that the residual current is 5mA at this time, the voltage added by R2 = I*R = 5mA*10Ω = 50mV. C18 and C20 are filter capacitors of the residual current transformer leads at both ends to ensure stable voltage output; C19 is a balancing capacitor between the leads at both ends of the residual current transformer to prevent voltage mutations between the two ends; D3 and D4 constitute a bidirectional diode protection tube to prevent overvoltage; R22 and R24 are current limiting resistors between the leads at both ends of the residual current transformer to prevent excessive signal voltage from breaking through the IO port of U4. The main control chip U4 determines the residual current value in the three-phase system by detecting the voltage value between IAP and IAN.

In the three-phase voltage monitoring module, R28, R33, and R39 are respectively the withstand voltage protection of A relative to N, B relative to N, and C relative to N to prevent lightning strikes from piercing the main control chip U4; R30, R35, and R36 are respectively the withstand voltage protection of A relative to B, B relative to C, and A relative to C to prevent excessive voltage difference between lines from piercing the main control chip U4; taking phase A as an example, assuming that the voltage of phase A is 220V at this time, R26 and R29 form a voltage divider circuit, that is, VAIN voltage = 220V*(R29/(R26+R29)) = 183mV, C24 is a filter capacitor to ensure a stable output voltage, and the main control chip U4 reads the voltage value of VAIN to determine whether there is any abnormality in the voltage at this moment, and calculates the single-phase voltage value at the same time.

The three-phase current monitoring module can monitor the current value of the cable in the distribution box. Here, phase A monitoring is taken as an example (the same applies to phases B and C). U2 is an open-type current transformer, which can convert the current on the primary cable side into a secondary proportional current through a transformation ratio. Here, U2 is a 3000:1 current transformer, and if the current on the primary side is 30A, the output current on the secondary side (i+, i-pin of U2) is 10mA. R1 and R5 are boost resistors to ground, which can convert the secondary current converted by U2 into a voltage output, that is, U1=i+*R1; R2 and R4 are current limiting resistors to prevent the voltage after the current transformer conversion from being too high and breaking through the IO port of the MCU; C1 and C5 are filter capacitors, which filter the converted voltage to be smoother. The module will monitor the current changes of the three-phase cable in real time and output the data to the MCU for data processing.

The three-phase line temperature measurement module can monitor the temperature changes of the three-phase line. Here, the temperature monitoring of phase A is taken as an example, where R46 is an NTC thermistor, which is pasted on the phase A line to measure the temperature change of phase A. R46 and R50 form a voltage divider circuit, that is, V = 3.3V*(10K/(R30+10K)). The microcontroller U4 judges the voltage change of V and converts it into a temperature value to judge whether it is overloaded, etc.; C36 is a filter capacitor to ensure that the output voltage V waveform is stable;

As shown in FIGS. 1 to 14 , the first embodiment of the present invention is:

An electrical fire monitoring device, comprising a power conversion circuit, a residual current collection module and a smoke sensing module, a main control chip, an RS485 communication module, a 4G communication module, a three-phase voltage monitoring module, a three-phase line temperature measurement module and a three-phase current measurement module;

Among them, the model of the main control chip is STM32F103C8T6.

In this embodiment, the three-phase voltage monitoring module includes an A-phase voltage monitoring circuit, a B-phase voltage monitoring circuit and a C-phase voltage monitoring circuit;

The A-phase voltage monitoring circuit includes a resistor R26, a resistor R28, a resistor R29 and a capacitor C24; one end of the resistor R28 is electrically connected to one end of the resistor R26, the other end of the resistor R28 is electrically connected to the resistor R29, the other end of the resistor R26 is electrically connected to the other end of the resistor R29, the capacitor C24 is connected in parallel with the resistor R29, and one end after the connection is electrically connected to the main control chip; the two ends of the resistor R28 are the two ends of the A-phase monitoring circuit, and are electrically connected to the A-phase line and the N line in the three-phase system;

The B-phase voltage monitoring circuit includes a resistor R32, a resistor R33, a resistor R34 and a capacitor C25; one end of the resistor R32 is electrically connected to one end of the resistor R33, the other end of the resistor R33 is electrically connected to the resistor R34, the other end of the resistor R32 is electrically connected to the other end of the resistor R34, the capacitor C25 is connected in parallel with the resistor R34, and one end after the connection is electrically connected to the main control chip; the two ends of the resistor R33 are the two ends of the B-phase monitoring circuit, and are electrically connected to the B-phase line and the N line in the three-phase system;

The C-phase voltage monitoring circuit includes resistor R38, resistor R39, resistor R40 and capacitor C30; one end of the resistor R38 is electrically connected to one end of the resistor R39, the other end of the resistor R39 is electrically connected to the resistor R40, the other end of the resistor R38 is electrically connected to the other end of the resistor R40, the capacitor C30 is connected in parallel with the resistor R40, and the connected end is electrically connected to the main control chip; the two ends of the resistor R39 are the two ends of the B-phase monitoring circuit, and are electrically connected to the C-phase line and the N line in the three-phase system.

The three-phase voltage monitoring module also includes a resistor R30, a resistor R35 and a resistor R36;

One end of the resistor R30 is electrically connected to one end of the resistor R26, and the other end of the resistor R30 is electrically connected to one end of the resistor R32;

One end of the resistor R35 is electrically connected to one end of the resistor R32, and the other end of the resistor R35 is electrically connected to one end of the resistor R38;

One end of the resistor R36 is electrically connected to one end of the resistor R26 , and the other end of the resistor R36 is electrically connected to one end of the resistor R38 .

Among them, the resistance value of resistor R26 is 1.2MΩ, the model of resistor R28 is 10D681K, the resistance value of resistor R29 is 1KΩ, and the capacitance value of capacitor C24 is 100nF;

The resistance value of resistor R32 is 1.2MΩ, the model of resistor R33 is 10D681K, the resistance value of resistor R34 is 1KΩ, and the capacitance value of capacitor C25 is 100nF;

The resistance value of resistor R38 is 1.2MΩ, the model of resistor R39 is 10D681K, the resistance value of resistor R40 is 1KΩ, and the capacitance value of capacitor C30 is 100nF;

The model of resistor R30 is 10D681K, the model of resistor R35 is 10D681K, and the model of resistor R36 is 10D681K.

In this embodiment, the three-phase current measurement module includes an A-phase current monitoring circuit, a B-phase current monitoring circuit and a C-phase current monitoring circuit;

The A-phase current monitoring circuit includes a current transformer U2, a resistor R1, a resistor R2, a resistor R4, a resistor R5, a capacitor C1 and a capacitor C5;

The I+ pin of the current transformer U2 is electrically connected to one end of the resistor R1 and one end of the resistor R2 respectively, the other end of the resistor R1 is grounded, the other end of the resistor R2 is electrically connected to one end of the capacitor C1, the other end of the capacitor C1 is grounded, and the other end of the resistor R2 is electrically connected to the main control chip;

The P1 pin and the P2 pin of the current transformer U2 are electrically connected to the A-phase primary cable;

The B-phase current monitoring circuit includes a current transformer U5, a resistor R9, a resistor R10, a resistor R14, a resistor R16, a capacitor C6 and a capacitor C9;

The I-pin of the current transformer U5 is electrically connected to one end of the resistor R16 and one end of the resistor R14 respectively, the other end of the resistor R16 is grounded, the other end of the resistor R14 is electrically connected to one end of the capacitor C9, the other end of the capacitor C9 is grounded, and the other end of the resistor R14 is electrically connected to the main control chip;

The P1 pin and the P2 pin of the current transformer U5 are electrically connected to the B-phase primary cable respectively;

The C-phase current monitoring circuit includes a current transformer U10, a resistor R18, a resistor R19, a resistor R20, a resistor R21, a capacitor C12 and a capacitor C17;

The I+ pin of the current transformer U10 is electrically connected to one end of the resistor R18 and one end of the resistor R19 respectively, the other end of the resistor R18 is grounded, the other end of the resistor R19 is electrically connected to one end of the capacitor C12, the other end of the capacitor C12 is grounded, and the other end of the resistor R19 is electrically connected to the main control chip;

The P1 pin and the P2 pin of the current transformer U10 are electrically connected to the C-phase primary cable.

Among them, the model of the current transformer U2 is ZEMCTK04, the resistance value of the resistor R1 is 7.5R, the resistance value of the resistor R2 is 1.2K, the resistance value of the resistor R4 is 1.2K, the resistance value of the resistor R5 is 7.5R, the specification of the capacitor C1 is 104, and the specification of the capacitor C5 is 104;

The model of the current transformer U5 is ZEMCTK04, the resistance value of the resistor R9 is 7.5Ω, the resistance value of the resistor R10 is 1.2KΩ, the resistance value of the resistor R14 is 1.2KΩ, the resistance value of the resistor R16 is 7.5Ω, the specification of the capacitor C6 is 104, and the specification of the capacitor C9 is 104;

The model of the current transformer U7 is ZEMCTK04, the resistance value of the resistor R18 is 7.5Ω, the resistance value of the resistor R19 is 1.2KΩ, the resistance value of the resistor R20 is 1.2KΩ, the resistance value of the resistor R21 is 7.5Ω, the specification of the capacitor C12 is 104, and the specification of the capacitor C17 is 104;

In this embodiment, the three-phase line temperature measurement module includes a phase A temperature measurement circuit, a phase B temperature measurement circuit and a phase C temperature measurement circuit;

The A-phase temperature measurement circuit includes a thermistor R46, a resistor R50 and a capacitor C36, one end of the resistor R50 is electrically connected to one end of the resistor R46 and one end of the capacitor C36 respectively, the other end of the capacitor C36 is grounded, the other end of the resistor R50 is grounded, and the other end of the resistor R36 is electrically connected to a 3.3V power supply of an external device; one end of the resistor R50 is electrically connected to the main control chip;

The B-phase temperature measurement circuit includes a thermistor R47, a resistor R51 and a capacitor C37, one end of the resistor R51 is electrically connected to one end of the resistor R47 and one end of the capacitor C36 respectively, the other end of the capacitor C37 is grounded, the other end of the resistor R51 is grounded, and the other end of the resistor R37 is electrically connected to a 3.3V power supply of an external device; one end of the resistor R51 is electrically connected to the main control chip;

The C-phase temperature measurement circuit includes a thermistor R48, a resistor R52 and a capacitor C38, one end of the resistor R52 is electrically connected to one end of the resistor R48 and one end of the capacitor C38 respectively, the other end of the capacitor C38 is grounded, the other end of the resistor R52 is grounded, and the other end of the resistor R36 is electrically connected to the 3.3V power supply of the peripheral device; one end of the resistor R52 is electrically connected to the main control chip.

Among them, the model of resistor R46 is NTC-10K, the resistance value of resistor R50 is 10KΩ, the capacitance value of capacitor C36 is 1uF, the model of resistor R47 is NTC-10K, the resistance value of resistor R51 is 10KΩ, the capacitance value of capacitor C37 is 1uF, the model of resistor R48 is NTC-10K, the resistance value of resistor R52 is 10KΩ, and the capacitance value of capacitor C38 is 1uF.

In this embodiment, the RS485 communication module includes a communication chip U10, a resistor R43, a resistor R44, a resistor R45, a single-phase suppression diode D6, a single-phase suppression diode D7 and a capacitor C31;

The eighth pin of the communication chip U10 is electrically connected to one end of the capacitor C31, and the other end of the capacitor C31 is grounded;

The seventh pin of the communication chip U10 is electrically connected to one end of the resistor R43, the sixth pin of the communication chip U10 is electrically connected to one end of the resistor R45, and both ends of the resistor R44 are electrically connected to the other end of the resistor R43 and the other end of the resistor R45 respectively;

The anode of the single-phase suppression diode D6 is grounded, and the cathode of the single-phase suppression diode D6 is electrically connected to the sixth pin of the communication chip U10. The anode of the single-phase suppression diode D7 is grounded, and the cathode of the single-phase suppression diode D7 is electrically connected to the seventh pin of the communication chip U10.

Among them, the model of the communication chip U10 is RS485, the resistance value of the resistor R43 is 10Ω, the resistance value of the resistor R44 is 120Ω, the resistance value of the resistor R45 is 10Ω, the model of the single-phase suppression diode D6 and the single-phase suppression diode D7 is P6SMB6.8A, and the capacitance value of the capacitor C31 is 1uF.

In this embodiment, the 4G communication module includes a 4G chip U8, a synchronous rectification step-down circuit, a voltage divider circuit, a level matching circuit and an indication circuit;

Among them, the model of 4G chip U8 is GM5.

The synchronous rectification and buck circuit includes a synchronous buck regulator U9, a resistor R25, a resistor R27, a resistor R31, a resistor R37, a resistor R41, a capacitor C21, a capacitor C22, a capacitor C23, a capacitor C26, a capacitor C27, a capacitor C28, a capacitor C29, an inductor L1 and a zener diode D5;

The second pin of the synchronous buck regulator U9 is electrically connected to one end of the resistor R25, and the other end of the resistor R25 is electrically connected to the external 5V power supply; the capacitor C21 is connected in parallel with the capacitor C22, and one end of the connected capacitor is electrically connected to the second pin of the synchronous buck regulator U9, and the other end of the connected capacitor is grounded; one end of the resistor R27 is electrically connected to the second pin of the synchronous buck regulator U9, and the other end of the resistor R27 is electrically connected to the seventh pin of the synchronous buck regulator U9;

The eighth pin of the synchronous buck regulator U9 is electrically connected to one end of the capacitor C26, the other end of the capacitor C26 is grounded, and the fourth pin of the synchronous buck regulator U9 is grounded;

The sixth pin of the synchronous buck regulator U9 is electrically connected to one end of the capacitor C27, the other end of the capacitor C27 is electrically connected to one end of the resistor R41, and the other end of the resistor R41 is grounded;

The first pin of the synchronous buck regulator U9 is electrically connected to one end of the capacitor C23, and the other end of the capacitor C23 is electrically connected to the third pin of the synchronous buck regulator U9;

The fifth pin of the synchronous buck regulator U9 is electrically connected to one end of the resistor R31 and one end of the resistor R37 respectively, and the other end of the resistor R37 is grounded; one end of the third pin of the synchronous buck regulator U9 is electrically connected to one end of the inductor L1, and the other end of the resistor R31 is electrically connected to the other end of the inductor L1; one end of the capacitor C28 is electrically connected to the other end of the inductor L1, and the other end of the capacitor C28 is grounded; one end of the capacitor C29 is electrically connected to the other end of the inductor L1, and the other end of the capacitor C29 is grounded; the cathode of the zener diode D5 is electrically connected to the other end of the inductor L1, and the anode of the zener diode D5 is grounded; the other end of the inductor L1 is electrically connected to the 4G chip U8;

Among them, the model of the synchronous buck regulator U9 is MP1482DS, the resistance value of the resistor R25 is 10Ω, the resistance value of the resistor R27 is 100KΩ, the resistance value of the resistor R31 is 31.6KΩ, the resistance value of the resistor R37 is 10KΩ, the resistance value of the resistor R41 is 2.2KΩ, the capacitance value of the capacitor C21 is 10uF, the capacitance value of the capacitor C22 is 10nF, the capacitance value of the capacitor C23 is 10nF, the capacitance value of the capacitor C26 is 100nF, the capacitance value of the capacitor C27 is 3nF, the capacitance value of the capacitor C28 is 47uF/6V3, the capacitance value of the capacitor C29 is 100nF, the parameter of the inductor L1 is 100uH, and the model of the Zener diode D5 is 1N4773;

In this embodiment, the level matching circuit includes a capacitor C39, a resistor R56, a resistor R57, a resistor R61, a resistor R62, a resistor R63, a resistor R64, a transistor Q3 and a transistor Q2;

The base of the transistor Q2 is electrically connected to one end of the resistor R61, the other end of the resistor R61 is electrically connected to the emitter of the transistor Q2, one end of the resistor R56 is electrically connected to the base of the transistor Q2, the other end of the resistor R56 is electrically connected to the 4G chip, one end of the resistor R62 is electrically connected to the collector of the transistor Q2, the other end of the resistor R62 is externally connected to a 3.3V power supply, and the emitter of the transistor Q2 is electrically connected to the 4G chip.

The base of the transistor Q3 is electrically connected to one end of the resistor R63, the other end of the resistor R63 is electrically connected to the collector of the transistor Q3, one end of the resistor R57 is electrically connected to the base of the transistor Q2, the other end of the resistor R57 is electrically connected to the 4G chip, one end of the capacitor C39 is electrically connected to the base of the transistor Q2, the other end of the capacitor C39 is electrically connected to the 4G chip, one end of the resistor R64 is electrically connected to the emitter of the transistor Q2, the other end of the resistor R64 is electrically connected to the 3.3V power supply of the external device, and the collector of the transistor Q2 is electrically connected to the 4G chip;

The level matching circuit includes a capacitor C39 having a capacitance of 33 pF, a resistor R56 having a resistance of 10 KΩ, a resistor R57 having a resistance of 10 KΩ, a resistor R61 having a resistance of 47 KΩ, a resistor R62 having a resistance of 4.7 KΩ, a resistor R63 having a resistance of 47 KΩ, a resistor R64 having a resistance of 4.7 KΩ, and transistors Q3 and Q2 having models of S9014;

The voltage divider circuit includes a resistor R49 and a resistor R58, one end of the resistor R49 is electrically connected to one end of the resistor R58 and a 3.3V power supply of an external device, the other end of the resistor R49 is electrically connected to a 3.8V power supply of an external device, and the other end of the resistor R58 is grounded.

The resistance value of the resistor R49 is 1.5KΩ, and the resistance value of the resistor R58 is 10KΩ.

The indicating circuit includes a transistor Q4, a transistor Q5, a resistor R53, a resistor R54, a resistor R55, a resistor R67, a resistor R68, a resistor R69, a resistor R70, a light emitting diode D8, a light emitting diode D9 and a light emitting diode D10;

The 4G chip is electrically connected to the base of the transistor Q4 through the resistor R67, the collector of the transistor Q4 is electrically connected to the cathode of the light-emitting diode D8, the anode of the light-emitting diode D8 is electrically connected to one end of the resistor R53, the other end of R53 is electrically connected to the external 3.3V power supply, one end of the resistor R69 is electrically connected to the base of the transistor Q4, the other end of the resistor R69 is grounded, and the emitter of the transistor Q4 is grounded;

The 4G chip is electrically connected to the base of the transistor Q5 through the resistor R68, the collector of the transistor Q5 is electrically connected to the cathode of the light-emitting diode D9, the anode of the light-emitting diode D9 is electrically connected to one end of the resistor R54, the other end of R54 is electrically connected to the external 3.3V power supply, one end of the resistor R70 is electrically connected to the base of the transistor Q5, the other end of the resistor R70 is grounded, and the emitter of the transistor Q5 is grounded;

One end of the resistor R55 is electrically connected to an external 3.3V power supply, the other end of the resistor R55 is electrically connected to the positive electrode of the light emitting diode D10, and the negative electrode of the light emitting diode D10 is grounded.

Wherein, the model of the transistor Q4 and the transistor Q5 is S9014, the resistance of the resistor R53 is 4.7KΩ, the resistance of the resistor R54 is 4.7KΩ, the resistance of the resistor R55 is 4.7KΩ, the resistance of the resistor R67 is 1KΩ, the resistance of the resistor R68 is 1KΩ, the resistance of the resistor R69 is 10KΩ, the resistance of the resistor R70 is 10KΩ, the model of the light-emitting diode D8 is LED-Y, the model of the light-emitting diode D9 is LED-G, and the model of the light-emitting diode D10 is LED-R;

In this embodiment, the 4G communication module further includes a SIM card slot J1, an electrostatic diode U11, a resistor R59, a resistor R60, a resistor R65, a resistor R66, a capacitor C32, a capacitor C33, a capacitor C34 and a capacitor C35;

The 4G chip is connected to the first pin of the SIM card slot J1, the 4G chip is electrically connected to one end of the resistor R60, the other end of the resistor R60 is connected to the second pin of the SIM card slot J1, the 4G chip is electrically connected to one end of the resistor R66, the other end of the resistor R66 is connected to the second pin of the SIM card slot J1;

One end of the capacitor C33 is electrically connected to one end of the resistor R60, and the other end of the capacitor C33 is grounded; one end of the capacitor C34 is electrically connected to one end of the resistor R66, and the other end of the capacitor C34 is grounded;

One end of the capacitor C32 is connected to the first pin of the SIM card slot J1, and the other end of the capacitor C32 is grounded; the first pin of the SIM card slot J1 is electrically connected to one end of the resistor R59, the other end of the resistor R59 is electrically connected to one end of the resistor R65, the other end of the resistor R65 is electrically connected to the sixth pin of the SIM card slot J1, one end of the capacitor C35 is electrically connected to one end of the resistor R65, the other end of the capacitor is grounded, and one end of the resistor R65 is electrically connected to the 4G chip;

The first pin of the electrostatic diode U11 is electrically connected to the first pin of the SIM card slot J1, and the sixth pin of the electrostatic diode U11 is electrically connected to one end of the resistor R60; the first pin of the electrostatic diode U11 is electrically connected to one end of the resistor R66; the fourth pin of the electrostatic diode U11 is electrically connected to one end of the resistor R65.

Among them, the 4G communication module also includes a SIM card slot J1 of model MICRO-SIM, an electrostatic diode U11 of model PESD5V0L5UV, a resistor R59 of 10KΩ, a resistor R60 of 22Ω, a resistor R65 of 22Ω, a resistor R66 of 22Ω, a capacitor C32 of 100nF, a capacitor C33 of 47pF, a capacitor C34 of 47pF, and a capacitor C35 of 47pF.

In this embodiment, the power conversion module includes a power conversion chip U3, an LDO chip U1, a varistor R3, a capacitor C2, a capacitor C3, a capacitor C4 and a capacitor E1;

The first pin and the second pin of the power conversion chip U3 are electrically connected to the external three-phase power supply respectively; one end of the varistor R33 is electrically connected to the first pin of the power conversion chip U3, and the other end of the varistor R33 is electrically connected to the second pin of the power conversion chip U3.

The fourth pin of U3 is electrically connected to the third pin of the LDO chip U1, and the other end of the connection is electrically connected to the third pin of the power conversion chip U3;

The capacitor C3 and the capacitor C2 are connected in parallel, one end of the connection is electrically connected to the second pin of the LDO chip U1, and the other end of the connection is grounded. The first pin of the LDO chip U1 is grounded.

Among them, the model of the power conversion chip U3 is POWRE-AC/DC-5V, the model of the LDO chip U1 is AMS1117-3.3, the model of the varistor R3 is 10D471K, the capacitance of the capacitor C2 is 1uF, the capacitance of the capacitor C3 is 100nF, the capacitance of the capacitor C4 is 100nF, and the capacitance of the capacitor E1 is 220uF/35V.

The capacitor C4 and the capacitor E1 are connected in parallel, and one end of the connected ends is connected to the power conversion chip

In this embodiment, the smoke sensor module includes a smoke sensor chip U6, a transistor Q1, a resistor R6, a resistor R7, a resistor R8, a resistor R11, a resistor R12, a resistor R15, a resistor R17, a light emitting diode D1, a light emitting diode D2 and a button S1;

The first pin of the smoke detection chip U6 is electrically connected to one end of the resistor R8, the other end of the resistor R8 is electrically connected to the positive electrode of the light emitting diode D1, and the negative electrode of the light emitting diode D1 is grounded;

The second pin of the smoke detection chip U6 is electrically connected to one end of the resistor R7, the other end of the resistor R7 is electrically connected to the positive electrode of the light emitting diode D2, and the negative electrode of the light emitting diode D2 is grounded;

The third pin of the smoke detection chip U6 is electrically connected to one end of the button S1, the other end of the button S1 is electrically connected to one end of the resistor R11, and the other end of the resistor R11 is electrically connected to the external 3.3V power supply;

The twelfth pin of the smoke detection chip U6 is grounded through a resistor R12;

The fourth pin of the smoke detection chip U6 is electrically connected to the base of the transistor Q1 through the resistor R15, one end of the resistor R17 is electrically connected to the base of the transistor Q1, and the other end of the resistor R17 is grounded; one end of the resistor R6 is electrically connected to the collector of the transistor Q1, and the other end of the resistor R6 is electrically connected to the external 3.3V power supply; the collector of the transistor Q1 is electrically connected to the main control chip.

Among them, the model of the detection chip U6 is SM100, the model of the transistor Q1 is SS8050, the resistance value of the resistor R6 is 10KΩ, the resistance value of the resistor R7 is 2KΩ, the resistance value of the resistor R8 is 2KΩ, the resistance value of the resistor R11 is 0Ω, the resistance value of the resistor R12 is 0Ω, the resistance value of the resistor R15 is 2KΩ, the resistance value of the resistor R17 is 10KΩ, the models of the light-emitting diodes D1 and D2 are LED-R, and the model of the button S1 is SW-PB;

In this embodiment, as shown in FIG. 8 , the residual current collection module includes a current transformer U10 , a resistor R22 , a resistor R23 , a resistor R24 , a capacitor C18 , a capacitor C18 , a capacitor C18 , a diode D3 , and a diode D4 .

Among them, the model of the current transformer U10 is ZEMCTK15, the resistance value of the resistor R22 is 100Ω, the resistance value of the resistor R23 is 10Ω, the resistance value of the resistor R24 is 100Ω, the capacitance value of the capacitor C18 is 100nF, the capacitance value of the capacitor C18 is 30nF, the capacitance value of the capacitor C18 is 100nF, and the models of the diode D3 and the diode D4 are 1N4148.

The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the contents of the present invention's specification and drawings, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims (10)

1. The electric fire monitoring device comprises a power supply conversion circuit, a residual current collection module, a smoke sensing module, and is characterized by further comprising a main control chip, an RS485 communication module, a 4G communication module, a three-phase voltage monitoring module, a three-phase line temperature measuring module and a three-phase current measuring module;

The main control chip is respectively and electrically connected with the RS485 communication module, the residual current collection module, the power supply conversion circuit, the three-phase voltage monitoring module, the three-phase line temperature measuring module, the three-phase current measuring module and the smoke sensing module, and is connected with the 4G communication module through wireless signals;

the residual current collection module, the three-phase voltage monitoring module and the three-phase current measuring module are respectively and electrically connected with an external three-phase system.

2. An electrical fire monitoring device as claimed in claim 1 wherein the three phase voltage monitoring module comprises an a phase voltage monitoring circuit, a B phase voltage monitoring circuit and a C phase voltage monitoring circuit;

The A-phase voltage monitoring circuit comprises a resistor R26, a resistor R28, a resistor R29 and a capacitor C24; one end of the resistor R28 is electrically connected with one end of the resistor R26, the other end of the resistor R28 is electrically connected with the resistor R29, the other end of the resistor R26 is electrically connected with the other end of the resistor R29, the capacitor C24 is connected with the resistor R29 in parallel, and one end after connection is electrically connected with the main control chip; the two ends of the resistor R28 are two ends of an A-phase monitoring circuit and are electrically connected with an A-phase line and an N-phase line in a three-phase system;

The B-phase voltage monitoring circuit comprises a resistor R32, a resistor R33, a resistor R34 and a capacitor C25; one end of the resistor R32 is electrically connected with one end of the resistor R33, the other end of the resistor R33 is electrically connected with the resistor R34, the other end of the resistor R32 is electrically connected with the other end of the resistor R34, the capacitor C25 is connected with the resistor R34 in parallel, and one end after connection is electrically connected with the main control chip; the two ends of the resistor R33 are two ends of a B-phase monitoring circuit and are electrically connected with a B-phase line and an N-phase line in a three-phase system;

The C-phase voltage monitoring circuit comprises a resistor R38, a resistor R39, a resistor R40 and a capacitor C30; one end of the resistor R38 is electrically connected with one end of the resistor R39, the other end of the resistor R39 is electrically connected with the resistor R40, the other end of the resistor R38 is electrically connected with the other end of the resistor R40, the capacitor C30 is connected with the resistor R40 in parallel, and one end after connection is electrically connected with the main control chip; and two ends of the resistor R39 are two ends of the B-phase monitoring circuit and are electrically connected with a C-phase line and an N-phase line in the three-phase system.

3. An electrical fire monitoring device as claimed in claim 2 wherein the three phase voltage monitoring module further comprises a resistor R30, a resistor R35 and a resistor R36;

One end of the resistor R30 is electrically connected with one end of the resistor R26, and the other end of the resistor R30 is electrically connected with one end of the resistor R32;

One end of the resistor R35 is electrically connected with one end of the resistor R32, and the other end of the resistor R35 is electrically connected with one end of the resistor R38;

one end of the resistor R36 is electrically connected to one end of the resistor R26, and the other end of the resistor R36 is electrically connected to one end of the resistor R38.

4. An electrical fire monitoring device as claimed in claim 1 wherein the three phase current measurement module comprises an a phase current monitoring circuit, a B phase current monitoring circuit and a C phase current monitoring circuit;

the A-phase current monitoring circuit comprises a current transformer U2, a resistor R1, a resistor R2, a resistor R4, a resistor R5, a capacitor C1 and a capacitor C5;

The I+ pin of the current transformer U2 is respectively and electrically connected with one end of a resistor R1 and one end of a resistor R2, the other end of the resistor R1 is grounded, the other end of the resistor R2 is electrically connected with one end of a capacitor C1, the other end of the capacitor C1 is grounded, and the other end of the resistor R2 is electrically connected with the main control chip;

the P1 pin and the P2 pin of the current transformer U2 are electrically connected with the A-phase primary cable;

the B-phase current monitoring circuit comprises a current transformer U5, a resistor R9, a resistor R10, a resistor R14, a resistor R16, a capacitor C6 and a capacitor C9;

The I-pin of the current transformer U5 is respectively and electrically connected with one end of a resistor R16 and one end of a resistor R14, the other end of the resistor R16 is grounded, the other end of the resistor R14 is electrically connected with one end of a capacitor C9, the other end of the capacitor C9 is grounded, and the other end of the resistor R14 is electrically connected with the main control chip;

the P1 pin and the P2 pin of the current transformer U5 are respectively and electrically connected with the B-phase primary cable;

The C-phase current monitoring circuit comprises a current transformer U10, a resistor R18, a resistor R19, a resistor R20, a resistor R21, a capacitor C12 and a capacitor C17;

The I+ pin of the current transformer U10 is respectively and electrically connected with one end of a resistor R18 and one end of a resistor R19, the other end of the resistor R18 is grounded, the other end of the resistor R19 is electrically connected with one end of a capacitor C12, the other end of the capacitor C12 is grounded, and the other end of the resistor R19 is electrically connected with the main control chip;

And the P1 pin and the P2 pin of the current transformer U10 are electrically connected with a C-phase primary cable.

5. The electrical fire monitoring device of claim 1, wherein the three-phase line temperature measurement module comprises an a-phase temperature measurement circuit, a B-phase temperature measurement circuit, and a C-phase temperature measurement circuit;

The A-phase temperature measuring circuit comprises a thermistor R46, a resistor R50 and a capacitor C36, wherein one end of the resistor R50 is respectively and electrically connected with one end of the resistor R46 and one end of the capacitor C36, the other end of the capacitor C36 is grounded, the other end of the resistor R50 is grounded, and the other end of the resistor R36 is electrically connected with a 3.3V power supply of the peripheral equipment; one end of the resistor R50 is electrically connected with the main control chip;

The B-phase temperature measuring circuit comprises a thermistor R47, a resistor R51 and a capacitor C37, wherein one end of the resistor R51 is respectively and electrically connected with one end of the resistor R47 and one end of the capacitor C36, the other end of the capacitor C37 is grounded, the other end of the resistor R51 is grounded, and the other end of the resistor R37 is electrically connected with a 3.3V power supply of the peripheral equipment; one end of the resistor R51 is electrically connected with the main control chip;

The C-phase temperature measuring circuit comprises a thermistor R48, a resistor R52 and a capacitor C38, wherein one end of the resistor R52 is respectively and electrically connected with one end of the resistor R48 and one end of the capacitor C38, the other end of the capacitor C38 is grounded, the other end of the resistor R52 is grounded, and the other end of the resistor R36 is electrically connected with a 3.3V power supply of the peripheral equipment; one end of the resistor R52 is electrically connected with the main control chip.

6. The electrical fire monitoring device of claim 1, wherein the RS485 communication module comprises a communication chip U10, a resistor R43, a resistor R44, a resistor R45, a single-phase suppressor diode D6, a single-phase suppressor diode D7, and a capacitor C31;

The eighth pin of the communication chip U10 is electrically connected to one end of the capacitor C31, and the other end of the capacitor C31 is grounded;

the seventh pin of the communication chip U10 is electrically connected with one end of the resistor R43, the sixth pin of the communication chip U10 is electrically connected with one end of the resistor R45, and two ends of the resistor R44 are respectively electrically connected with the other end of the resistor R43 and the other end of the resistor R45;

the positive electrode of the single-phase suppression diode D6 is grounded, the negative electrode of the single-phase suppression diode D6 is electrically connected with the sixth pin of the communication chip U10, the positive electrode of the single-phase suppression diode D7 is grounded, and the negative electrode of the single-phase suppression diode D7 is electrically connected with the seventh pin of the communication chip U10.

7. The electrical fire monitoring device of claim 1, wherein the 4G communication module comprises a 4G chip U8, a synchronous rectification step-down circuit, a voltage dividing circuit, a level matching circuit and an indicating circuit;

The synchronous rectification step-down circuit comprises a synchronous step-down voltage stabilizer U9, a resistor R25, a resistor R27, a resistor R31, a resistor R37, a resistor R41, a capacitor C21, a capacitor C22, a capacitor C23, a capacitor C26, a capacitor C27, a capacitor C28, a capacitor C29, an inductor L1 and a voltage stabilizing diode D5;

The second pin of the synchronous buck regulator U9 is electrically connected with one end of a resistor R25, and the other end of the resistor R25 is electrically connected with a peripheral 5V power supply; the capacitor C21 is connected in parallel with the capacitor C22, one end after connection is electrically connected with the second pin of the synchronous buck regulator U9, and the other end after connection is grounded; one end of the resistor R27 is electrically connected with the second pin of the synchronous buck regulator U9, and the other end of the resistor R27 is electrically connected with the seventh pin of the synchronous buck regulator U9;

An eighth pin of the synchronous buck regulator U9 is electrically connected with one end of the capacitor C26, the other end of the capacitor C26 is grounded, and a fourth pin of the synchronous buck regulator U9 is grounded;

A sixth pin of the synchronous buck regulator U9 is electrically connected with one end of a capacitor C27, the other end of the capacitor C27 is electrically connected with one end of a resistor R41, and the other end of the resistor R41 is grounded;

The first pin of the synchronous buck regulator U9 is electrically connected with one end of a capacitor C23, and the other end of the capacitor C23 is electrically connected with the third pin of the synchronous buck regulator U9;

The fifth pin of the synchronous buck regulator U9 is respectively and electrically connected with one end of a resistor R31 and one end of a resistor R37, and the other end of the resistor R37 is grounded; one end of a third pin of the synchronous buck regulator U9 is electrically connected with one end of the inductor L1, and the other end of the resistor R31 is electrically connected with the other end of the inductor L1; one end of the capacitor C28 is electrically connected with the other end of the inductor L1, and the other end of the capacitor C28 is grounded; one end of the capacitor C29 is electrically connected with the other end of the inductor L1, and the other end of the capacitor C29 is grounded; the negative electrode of the voltage stabilizing diode D5 is electrically connected with the other end of the inductor L1, and the positive electrode of the voltage stabilizing diode D5 is grounded; the other end of the inductor L1 is electrically connected with the 4G chip U8;

The level matching circuit comprises a capacitor C39, a resistor R56, a resistor R57, a resistor R61, a resistor R62, a resistor R63, a resistor R64, a triode Q3 and a triode Q2;

The base electrode of the triode Q2 is electrically connected with one end of a resistor R61, the other end of the resistor R61 is electrically connected with the emitter electrode of the triode Q2, one end of a resistor R56 is electrically connected with the base electrode of the triode Q2, the other end of the resistor R56 is electrically connected with a 4G chip, one end of a resistor R62 is electrically connected with the collector electrode of the triode Q2, the other end of the resistor R62 is externally connected with a 3.3V power supply, and the emitter electrode of the triode Q2 is electrically connected with the 4G chip;

the base electrode of the triode Q3 is electrically connected with one end of the resistor R63, the other end of the resistor R63 is electrically connected with the collector electrode of the triode Q3, one end of the resistor R57 is electrically connected with the base electrode of the triode Q2, the other end of the resistor R57 is electrically connected with the 4G chip, one end of the capacitor C39 is electrically connected with the base electrode of the triode Q2, the other end of the capacitor C39 is electrically connected with the 4G chip, one end of the resistor R64 is electrically connected with the emitter electrode of the triode Q2, the other end of the resistor R64 is electrically connected with a peripheral 3.3V power supply, and the collector electrode of the triode Q2 is electrically connected with the 4G chip;

The voltage dividing circuit comprises a resistor R49 and a resistor R58, wherein one end of the resistor R49 is respectively and electrically connected with one end of the resistor R58 and a 3.3V power supply of the peripheral equipment, the other end of the resistor R49 is electrically connected with the 3.8V power supply of the peripheral equipment, and the other end of the resistor R58 is grounded;

The indicating circuit comprises a triode Q4, a triode Q5, a resistor R53, a resistor R54, a resistor R55, a resistor R67, a resistor R68, a resistor R69, a resistor R70, a light emitting diode D8, a light emitting diode D9 and a light emitting diode D10;

The 4G chip is electrically connected with the base electrode of the triode Q4 through a resistor R67, the collector electrode of the triode Q4 is electrically connected with the negative electrode of the light-emitting diode D8, the positive electrode of the light-emitting diode D8 is electrically connected with one end of the resistor R53, the other end of the resistor R53 is electrically connected with a peripheral 3.3V power supply, one end of the resistor R69 is electrically connected with the base electrode of the triode Q4, the other end of the resistor R69 is grounded, and the emitter electrode of the triode Q4 is grounded;

The 4G chip is electrically connected with the base electrode of the triode Q5 through a resistor R68, the collector electrode of the triode Q5 is electrically connected with the negative electrode of the light-emitting diode D9, the positive electrode of the light-emitting diode D9 is electrically connected with one end of the resistor R54, the other end of the resistor R54 is electrically connected with a peripheral 3.3V power supply, one end of the resistor R70 is electrically connected with the base electrode of the triode Q5, the other end of the resistor R70 is grounded, and the emitter electrode of the triode Q5 is grounded;

one end of the resistor R55 is electrically connected with a peripheral 3.3V power supply, the other end of the resistor R55 is electrically connected with the positive electrode of the light emitting diode D10, and the negative electrode of the light emitting diode D10 is grounded.

8. The electrical fire monitoring device of claim 7, wherein the 4G communication module further comprises a SIM card slot J1, an electrostatic diode U11, a resistor R59, a resistor R60, a resistor R65, a resistor R66, a capacitor C32, a capacitor C33, a capacitor C34, and a capacitor C35;

The 4G chip is connected with a first pin of the SIM card slot J1, the 4G chip is electrically connected with one end of the resistor R60, the other end of the resistor R60 is connected with a second pin of the SIM card slot J1, the 4G chip is electrically connected with one end of the resistor R66, and the other end of the resistor R66 is connected with the second pin of the SIM card slot J1;

one end of the capacitor C33 is electrically connected with one end of the resistor R60, and the other end of the capacitor C33 is grounded; one end of the capacitor C34 is electrically connected with one end of the resistor R66, and the other end of the capacitor C34 is grounded;

One end of the capacitor C32 is connected with the first pin of the SIM card slot J1, and the other end of the capacitor C32 is grounded; the first pin of the SIM card slot J1 is electrically connected with one end of the resistor R59, the other end of the resistor R59 is electrically connected with one end of the resistor R65, the other end of the resistor R65 is electrically connected with the sixth pin of the SIM card slot J1, one end of the capacitor C35 is electrically connected with one end of the resistor R65, the other end of the capacitor is grounded, and one end of the resistor R65 is electrically connected with the 4G chip;

A first pin of the electrostatic diode U11 is electrically connected with a first pin of the SIM card slot J1, and a sixth pin of the electrostatic diode U11 is electrically connected with one end of the resistor R60; the first pin of the electrostatic diode U11 is electrically connected with one end of the resistor R66; the fourth pin of the electrostatic diode U11 is electrically connected to one end of the resistor R65.

9. The electrical fire monitoring device of claim 1, wherein the power conversion module comprises a power conversion chip U3, an LDO chip U1, a varistor R3, a capacitor C2, a capacitor C3, a capacitor C4, and a capacitor E1;

The first pin and the second pin of the power conversion chip U3 are respectively and electrically connected with an external three-phase power supply; one end of the piezoresistor R33 is electrically connected with a first pin of the power conversion chip U3, and the other end of the piezoresistor R33 is electrically connected with a second pin of the power conversion chip U3;

The capacitor C4 and the capacitor E1 are connected in parallel, one end after connection is respectively and electrically connected with a fourth pin of the power conversion chip U3 and a third pin of the LDO chip U1, and the other end after connection is electrically connected with the third pin of the power conversion chip U3;

The capacitor C3 and the capacitor C2 are connected in parallel, one end of the capacitor C3 is electrically connected with the second pin of the LDO chip U1, the other end of the capacitor C3 is grounded, and the first pin of the LDO chip U1 is grounded.

10. The electrical fire monitoring device of claim 1, wherein the smoke sensing module comprises a smoke sensing chip U6, a triode Q1, a resistor R6, a resistor R7, a resistor R8, a resistor R11, a resistor R12, a resistor R15, a resistor R17, a light emitting diode D1, a light emitting diode D2 and a key S1;

the first pin of the smoke detection chip U6 is electrically connected with one end of a resistor R8, the other end of the resistor R8 is electrically connected with the positive electrode of the light emitting diode D1, and the negative electrode of the light emitting diode D1 is grounded;

the second pin of the smoke detection chip U6 is electrically connected with one end of a resistor R7, the other end of the resistor R7 is electrically connected with the positive electrode of the light emitting diode D2, and the negative electrode of the light emitting diode D2 is grounded;

the third pin of the smoke detection chip U6 is electrically connected with one end of a key S1, the other end of the key S1 is electrically connected with one end of a resistor R11, and the other end of the resistor R11 is electrically connected with a peripheral 3.3V power supply;

the twelfth pin of the smoke detection chip U6 is grounded through a resistor R12;

The fourth pin of the smoke detection chip U6 is electrically connected with the base electrode of the triode Q1 through a resistor R15, one end of the resistor R17 is electrically connected with the base electrode of the triode Q1, and the other end of the resistor R17 is grounded; one end of the resistor R6 is electrically connected with the collector electrode of the triode Q1, and the other end of the resistor R6 is electrically connected with a peripheral 3.3V power supply; and the collector electrode of the triode Q1 is electrically connected with the main control chip.