An integrated electrical fire monitoring system

Abstract

This utility model discloses an integrated electrical fire monitoring system, relating to the field of fire alarm technology. When monitoring electrical fires, it improves the comprehensiveness of monitoring by using multiple sensors and video surveillance linkage. It monitors and records various parameters of electrical equipment groups, transmits data, receives and sends signals through a microcontroller module, and processes alarms through an alarm mechanism. By monitoring electrical circuits and detecting electrical fires, it monitors parameters such as current, voltage, and power of electrical circuits to promptly detect electrical faults and monitor for potential fire hazards. The comprehensiveness of electrical fire monitoring is enhanced through video surveillance linkage, so that the system will issue an alarm signal and link relevant equipment for control and processing upon detecting abnormalities, thereby improving the reliability and timeliness of the electrical fire monitoring system.

Description

Technical Field

[0001] This utility model belongs to the field of intelligent fire alarm technology, and in particular relates to an integrated electrical fire monitoring system. Background Technology

[0002] Electrical fires have a wide impact and cause serious economic losses. Most existing electrical fire monitoring systems use electrical fire detectors to monitor the circuits of electrical equipment. This single monitoring method has certain safety hazards and cannot perform fire assessment and analysis on the monitored equipment based on changes in monitoring data, predict potential fire hazards in advance, or improve safety.

[0003] With the improvement of residents' living standards, the number of electrical appliances has increased significantly, and the electricity consumption of civil buildings has also increased year by year. Consequently, electrical fires caused directly or indirectly by electrical wiring have also increased. According to relevant statistics, for example, of the 115 fires identified in 2002, 95 were electrical fires, highlighting the urgent need to strengthen the prevention of electrical fires. Electrical fires have many causes, including short circuits, overheating, leakage current, lightning strikes, and electrical faults, and their hazards are considerable. Therefore, fires caused by all reasons should be effectively controlled. Currently, protection measures against short circuits, overheating, and lightning strikes are becoming increasingly mature. However, due to the widespread presence of normal leakage current, leakage current is often not given sufficient attention, leading to fires. Clearly, alarm systems that use leakage current detection to provide fire early warnings are essential. With the successive promulgation of relevant product standards and design specifications in my country, the application of leakage current fire alarm systems, i.e., electrical fire monitoring systems, in engineering projects has been promoted.

[0004] Existing electrical fire monitoring systems have relatively outdated technology for monitoring fires caused by leakage current, resulting in low reliability. Furthermore, they can only alarm and control the fire by monitoring leakage current in the circuit, and cannot provide comprehensive monitoring of other fault causes that may lead to electrical fires. Utility Model Content

[0005] The technical problem to be solved by this utility model is to address the shortcomings of the existing technology by proposing an integrated electrical fire monitoring system. When monitoring electrical fires, the system uses temperature sensors, smoke sensors, combustible gas concentration detection units, current transformers, and voltage transformers, along with video monitoring linkage, to improve the comprehensiveness of electrical fire monitoring. It monitors and records and transmits various parameters of the electrical equipment group, receives and feeds back signals through a microcontroller module, and handles alarms through an alarm mechanism. The alarm mechanism evacuates people and contacts professional personnel to promptly eliminate electrical fires and protect property, thus achieving the effect of timely monitoring of electrical equipment groups.

[0006] To solve the above-mentioned technical problems, this utility model adopts the following technical solution:

[0007] An integrated electrical fire monitoring system includes a temperature sensor, a smoke sensor, a combustible gas concentration detection unit, a current transformer, a voltage transformer, a multiplexer, a signal processing module, an analog-to-digital converter, a microcontroller module, an image acquisition module, a positioning module, a voice broadcast module, a fire alarm module, a maintenance call module, an HDMI interface chip control unit, an HDMI interface circuit, and a power supply module. The outputs of the temperature sensor, smoke sensor, combustible gas concentration detection unit, current transformer, and voltage transformer are respectively connected to the input of the multiplexer. The output of the multiplexer is connected to the input of the signal processing module. The output of the signal processing module is connected to the input of the analog-to-digital converter. The output of the analog-to-digital converter is connected to the input of the microcontroller module. The output of the image acquisition module is connected to the input of the microcontroller module. The output of the positioning module is connected to the input of the microcontroller module. The output of the microcontroller module is connected to the inputs of the voice broadcast module, fire alarm module, and maintenance call module. The microcontroller module is connected to the HDMI interface circuit via the HDMI interface chip control unit. The power supply module is connected to the microcontroller module to provide the required power.

[0008] As a further preferred embodiment of the integrated electrical fire monitoring system of this utility model, the signal processing module includes a sensor signal conditioning circuit, a current signal conditioning circuit, a voltage signal conditioning circuit, a voltage divider follower filter circuit, and an A / D converter. The multiplexer switch is connected to the microcontroller module in sequence through the sensor signal conditioning circuit, the current signal conditioning circuit, the voltage signal conditioning circuit, the voltage divider follower filter circuit, and the A / D converter.

[0009] As a further preferred embodiment of the integrated electrical fire monitoring system of this utility model, the image acquisition module includes a CMOS image sensor, an input FIFO module, a DDR controller, an image parameter calculation module, a DDR2 SDRAM, and an output FIFO module. The output terminal of the CMOS image sensor is connected to the input terminal of the input FIFO module, the output terminal of the input FIFO module is connected to the input terminal of the DDR2 SDRAM, the output terminal of the DDR2 SDRAM is connected to the input terminal of the output FIFO module, the output terminal of the image parameter calculation module is also connected to the input terminal of the DDR2 SDRAM through the DDR controller, and the output terminal of the output FIFO module is connected to the input terminal of the main control module.

[0010] As a further preferred embodiment of the integrated electrical fire monitoring system of this utility model, the sensor signal conditioning circuit includes an analog signal input terminal, resistors R1 and R2, capacitor C1, and operational amplifier U1. The analog signal input terminal is connected to one end of resistor R1 and one end of resistor R2, the other end of resistor R2 is connected to one end of capacitor C1, the other end of capacitor C1 is connected to the other end of resistor R1 and the positive input terminal of operational amplifier U1, and the negative input terminal of operational amplifier U1 is connected to the output terminal of operational amplifier U1.

[0011] As a further preferred embodiment of the integrated electrical fire monitoring system of this utility model, the voltage signal conditioning circuit includes a voltage signal input terminal, resistors R3, R4, and R5, capacitor C2, and operational amplifier U2. The voltage signal input terminal is connected to one end of resistor R3, the other end of resistor R3 is connected to one end of resistor R4 and one end of resistor R5, the other end of resistor R5 is connected to one end of capacitor C2, the other end of capacitor C2 is connected to the other end of resistor R4 and the positive input terminal of operational amplifier U1, and the negative input terminal of operational amplifier U2 is connected to the output terminal of operational amplifier U2.

[0012] As a further preferred embodiment of the integrated electrical fire monitoring system of this utility model, the voltage divider follower filter circuit includes an operational amplifier U3, resistors R11 and R12, an operational amplifier U4, resistors R13, and a capacitor C7. The output terminal of the operational amplifier U3 is connected to one end of resistor R12, and the other end of resistor R12 is connected to one end of resistor R11 and the positive input terminal of operational amplifier U4. The output terminal of operational amplifier U4 is connected to one end of resistor R13, and the other end of resistor R13 is connected to one end of capacitor C7 and the A / D conversion unit. The other end of capacitor C7 is grounded, and the other end of resistor R11 is connected to the current signal conditioning circuit.

[0013] Compared with the prior art, the present invention, by adopting the above technical solution, has the following technical effects:

[0014] This utility model discloses an integrated electrical fire monitoring system. When monitoring electrical fires, it utilizes temperature sensors, smoke sensors, combustible gas concentration detection units, current transformers, and voltage transformers, along with video surveillance linkage to enhance the comprehensiveness of electrical fire monitoring. It monitors and records various parameters of the electrical equipment group, transmits data, receives and sends signals through a microcontroller module, and triggers an alarm mechanism. The alarm mechanism facilitates the evacuation of people and contacts professional personnel to promptly extinguish the electrical fire and protect property. This system provides timely monitoring of electrical equipment groups. By monitoring electrical circuits and detecting electrical fires, it monitors parameters such as current, voltage, and power to promptly identify electrical faults and monitor for potential fire hazards. The comprehensiveness of electrical fire monitoring is enhanced by video surveillance linkage, ensuring that the system issues an alarm signal and triggers relevant equipment for control and handling upon detecting abnormalities, thereby improving the reliability and timeliness of the electrical fire monitoring system. Attached Figure Description

[0015] The accompanying drawings, which are provided to further illustrate the present invention and form part of this application, do not constitute an undue limitation of the present invention. In the drawings:

[0016] Figure 1 This is a structural schematic diagram of an integrated electrical fire monitoring system according to this utility model;

[0017] Figure 2 This is a schematic diagram of the signal processing module of this utility model;

[0018] Figure 3 This is a schematic diagram of the image acquisition module of this utility model;

[0019] Figure 4 This is a circuit diagram of the sensor signal conditioning circuit of this utility model;

[0020] Figure 5 This is a circuit diagram of the voltage signal conditioning circuit of this utility model;

[0021] Figure 6 This is the circuit diagram of the voltage divider follower filter circuit of this utility model. Detailed Implementation

[0022] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings:

[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0025] In the description of this utility model, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0026] An integrated electrical fire monitoring system, such as Figure 1 As shown, the system includes a temperature sensor, a smoke sensor, a combustible gas concentration detection unit, a current transformer, a voltage transformer, a multiplexer, a signal processing module, an analog-to-digital converter, a microcontroller module, an image acquisition module, a positioning module, a voice broadcast module, a fire alarm module, a maintenance call module, an HDMI interface chip control unit, an HDMI interface circuit, and a power supply module. The outputs of the temperature sensor, smoke sensor, combustible gas concentration detection unit, current transformer, and voltage transformer are respectively connected to the input of the multiplexer. The output of the multiplexer is connected to the input of the signal processing module. The output of the signal processing module is connected to the input of the analog-to-digital converter. The output of the analog-to-digital converter is connected to the input of the microcontroller module. The output of the image acquisition module is connected to the input of the microcontroller module. The output of the positioning module is connected to the input of the microcontroller module. The outputs of the microcontroller module are respectively connected to the inputs of the voice broadcast module, fire alarm module, and maintenance call module. The microcontroller module is connected to the HDMI interface circuit via the HDMI interface chip control unit. The power supply module is connected to the microcontroller module to provide the required power.

[0027] The temperature sensor is connected to the electrical fire monitoring host and provides real-time feedback to the electrical equipment group.

[0028] Temperature data;

[0029] The combustible gas concentration detection unit is used to collect combustible gas concentration parameters; the current transformer is installed on the electrical equipment group, and the current transformer is connected to each electrical device and feeds back data to the electrical fire monitoring host; the voltage transformer is connected to the motor fire monitoring host and is connected to each electrical device and feeds back voltage data in real time; the smoke sensor is installed on the electrical equipment group, and the smoke sensor monitors and feeds back the smoke generation of the electrical equipment group and transmits data to the electrical fire monitoring host; the electrical fire monitoring host is used to collect and analyze temperature data, current data, voltage data and smoke data and determine whether a fire has occurred.

[0030] The image acquisition module is used to improve the comprehensiveness of electrical fire monitoring through video surveillance linkage;

[0031] The voice broadcast module broadcasts details of electrical fire warnings and disperses nearby crowds.

[0032] The fire alarm module contacts the local fire department, police station and health department to handle fires promptly.

[0033] The maintenance call module is used to call the on-duty engineer to promptly stop the operation of the electrical equipment group and contact the on-duty engineer for electrical maintenance to eliminate potential electrical fire hazards before a fire occurs.

[0034] This utility model discloses an integrated electrical fire monitoring system. When monitoring electrical fires, it utilizes temperature sensors, smoke sensors, combustible gas concentration detection units, current transformers, and voltage transformers, along with video surveillance linkage to enhance the comprehensiveness of electrical fire monitoring. It monitors and records various parameters of the electrical equipment group, receives and transmits signals through a microcontroller module, and triggers an alarm mechanism. The alarm mechanism facilitates the evacuation of people and contacts professional personnel to promptly extinguish the electrical fire and protect property. This system provides timely monitoring of electrical equipment groups. By monitoring electrical circuits and detecting electrical fires, it monitors parameters such as current, voltage, and power of the electrical circuits to promptly identify electrical faults and monitor for potential fire hazards. The comprehensiveness of electrical fire monitoring is enhanced through video surveillance linkage, ensuring that the system issues an alarm signal and triggers relevant equipment for control and handling upon detecting abnormalities, thereby improving the reliability and timeliness of the electrical fire monitoring system.

[0035] like Figure 2As shown, the signal processing module includes a sensor signal conditioning circuit, a current signal conditioning circuit, a voltage signal conditioning circuit, a voltage divider follower filter circuit, and an A / D converter. The multiplexer switch is connected to the microcontroller module in sequence through the sensor signal conditioning circuit, the current signal conditioning circuit, the voltage signal conditioning circuit, the voltage divider follower filter circuit, and the A / D converter.

[0036] like Figure 3 As shown, the image acquisition module includes a CMOS image sensor, an input FIFO module, a DDR controller, an image parameter calculation module, a DDR2 SDRAM, and an output FIFO module. The output terminal of the CMOS image sensor is connected to the input terminal of the input FIFO module, the output terminal of the input FIFO module is connected to the input terminal of the DDR2 SDRAM, the output terminal of the DDR2 SDRAM is connected to the input terminal of the output FIFO module, the output terminal of the image parameter calculation module is also connected to the input terminal of the DDR2 SDRAM through the DDR controller, and the output terminal of the output FIFO module is connected to the input terminal of the main control module.

[0037] The video capture module uses OminiVision's 5-megapixel CMOS image sensor OV5640 as the front-end capture camera to achieve efficient video data caching. At the same time, it uses Silion Image's SiI9134 as the HDMI chip, which can effectively support full HD video.

[0038] The data caching module adopts a three-level data caching mechanism, which utilizes the high-efficiency read and write performance of the internal FIFO and the large-capacity external DDR2 storage to form a complementary advantage in terms of speed and capacity (time and space), which well meets the performance requirements of high-speed image data transmission systems for image data transmission.

[0039] like Figure 4 As shown, the sensor signal conditioning circuit includes an analog signal input terminal, resistors R1 and R2, capacitor C1, and operational amplifier U1. The analog signal input terminal is connected to one end of resistor R1 and one end of resistor R2, respectively. The other end of resistor R2 is connected to one end of capacitor C1, and the other end of capacitor C1 is connected to the other end of resistor R1 and the positive input terminal of operational amplifier U1. The negative input terminal of operational amplifier U1 is connected to the output terminal of operational amplifier U1.

[0040] As a key component of the conditioning circuit, the operational amplifier is selected from the AD8608 operational amplifier chip of ADI. This chip combines many excellent features, has four rail input and output while being powered by a single power supply, and can ensure high speed while also ensuring extremely low noise and input bias current. It is widely applicable to various circuits.

[0041] Since the input impedance of operational amplifiers is generally very high, they are easily affected by external interference when the input pin is left floating. Therefore, setting resistor R2 can make the input terminal form a loop with the analog ground when the input pin is left floating, thus ensuring the stability of the operational amplifier.

[0042] like Figure 5 As shown, the voltage signal conditioning circuit includes a voltage signal input terminal, resistors R3, R4, and R5, capacitor C2, and operational amplifier U2. The voltage signal input terminal is connected to one end of resistor R3. The other end of resistor R3 is connected to one end of resistor R4 and one end of resistor R5. The other end of resistor R5 is connected to one end of capacitor C2. The other end of capacitor C2 is connected to the other end of resistor R4 and the positive input terminal of operational amplifier U1. The negative input terminal of operational amplifier U2 is connected to the output terminal of operational amplifier U2.

[0043] In voltage conditioning circuits, rail-to-rail operational amplifiers can maximize the input and output voltage swings to be close to the power supply voltage. However, there is still a large deviation under high current conditions. Since the input voltage range of AD8608 is 0 to 0.5V, a voltage divider circuit is set up with resistors R3 and R5 to reduce the input voltage to below 5V.

[0044] Depending on the magnitude of the current and whether it is AC or DC, the corresponding current acquisition methods vary. Commonly used current acquisition methods include the coaxial shunt method, current transformer method, Rogowski coil method, Hall sensor method, and sampling resistor method. The Hall sensor method is suitable for both AC and DC current measurement and can perform large current measurements. The current signal conditioning circuit uses the Allegro ACS714 chip, which is a current-isolated current sensor with common-mode rejection, composed of a high-precision, low-bias linear Hall sensor.

[0045] The analog switch is controlled by FPGA to select and switch channels to achieve time-division multiplexing. When switching channels, the analog switch will affect the change of capacitive load, resulting in phenomena such as signal oscillation or ringing. The faster the analog switch switches, the more obvious this phenomenon will be. Therefore, the selection of analog switch is particularly important. After analyzing and comparing various types of analog switches, this design adopts the ADG706 chip.

[0046] like Figure 6As shown, the voltage divider follower filter circuit includes operational amplifier U3, resistors R11 and R12, operational amplifier U4, resistor R13, and capacitor C7. The output terminal of operational amplifier U3 is connected to one end of resistor R12. The other end of resistor R12 is connected to one end of resistor R11 and the positive input terminal of operational amplifier U4. The output terminal of operational amplifier U4 is connected to one end of resistor R13. The other end of resistor R13 is connected to one end of capacitor C7 and the A / D conversion unit. The other end of capacitor C7 is grounded. The other end of resistor R11 is connected to the current signal conditioning circuit.

[0047] The signal passes through a voltage divider / follower / filter circuit after passing through an analog switch, and is then input to the AD converter. The voltage follower makes the circuit present a high-impedance input and a low-impedance output, improving the circuit's load-driving capability. The operational amplifiers U3 and U4 are AD8031 chips. The maximum sampling current of the ACS714 chip is 5A.

[0048] The system control core uses the Xilinx Spartan 6 series chip XC6SLX45. The sixth-generation Spartan 6 FPGA is based on the widely recognized low-power 45nm, 9-metal copper layer, dual-gate oxide process technology, providing advanced power management technology, 150,000 logic cells, hard-core DRAM memory, and various IPs. It is one of Xlinx's most widely used and technologically mature FPGA series. The FPGA main control module primarily handles camera configuration and video data acquisition, DDR3-SDRAM data storage and retrieval, and HDMI interface chip configuration and video data transmission. Its hardware circuitry also includes power supply circuitry, reset circuitry, crystal oscillator circuitry, download circuitry, and SPI Flash configuration circuitry.

[0049] The OV5640 has specific power-on timing requirements, so modules that meet these requirements are essential. After initialization, the OV5640's operating mode is determined via the SCCB bus. This system has 303 registers configured. Once the OV5640 is configured and the DDR3-SDRAM is initialized and calibrated, video data can be acquired. Controlling the OV5640 requires providing a system clock XVCLK of 192MHz, and then identifying the pixel output clock (PCLK), vertical sync signal (VSYNC), and horizontal sync signal (HREF) to acquire data. The falling edge of the vertical sync signal indicates the start of a frame of data. A high level on the horizontal sync signal indicates valid data output. Between low levels on the vertical sync signal, the horizontal sync signal will be high 1080 times, representing 1080 lines of data per frame. During the high level period of the horizontal sync signal, there will be 1920 pixel output clock cycles, representing 1920 pixels per line.

[0050] To address the caching issue of high-speed, high-capacity video data, this system uses the Micron MT41J256M16HA-125 4Gbit DDR3-SDRAM memory chip as the cache medium. A0-A14 are the address bus, B0-B3 are the Bank addresses; the FPGA controls the data storage location in the DDR3-SDRAM by controlling the address bus and Bank addresses. D0-D15 are the data bus, connected in parallel with the FPGA. CLK-N and CLK-P are differential clock input ports; the clock frequency in this system is set to 312.5MHz. The FPGA controls the read and write operations of the DDR3-SDRAM through the Column Address Select (CAS), Row Address Select (RAS), and Write Enable (WE) signals. Performance optimization is achieved by controlling the ODT to enable on-chip resistors and prevent data line interruption reflections. DQS is the synchronization signal between the DDR3-SDRAM and the controller; it is bidirectional, issued by the controller when writing data and by the memory when reading data. DM is the data mask signal. Since only Bank1 and Bank3 of the Spartan6 series FPGA have MCB hard cores, in this system, Bank3 of the FPGA is connected to DDR3-SDRAM with a port voltage standard of 1.5V. In the FPGA UCF, the IO standard needs to be set to SSTL15_II.

[0051] Finally, the following points should be noted: First, in the description of this application, it should be noted that, unless otherwise specified and limited, the terms "installation", "connection", and "linkage" should be interpreted broadly, and can be mechanical or electrical connections, or internal connections between two components, or direct connections. "Up", "down", "left", "right", etc. are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may change.

[0052] Secondly: The accompanying drawings of the embodiments disclosed in this utility model only involve the structures involved in the embodiments disclosed in this utility model. Other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of this utility model can be combined with each other.

[0053] Finally: The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An integrated electrical fire monitoring system, characterized in that: The system includes a temperature sensor, a smoke sensor, a combustible gas concentration detection unit, a current transformer, a voltage transformer, a multiplexer, a signal processing module, an analog-to-digital converter, a microcontroller module, an image acquisition module, a positioning module, a voice broadcast module, a fire alarm module, a maintenance call module, an HDMI interface chip control unit, an HDMI interface circuit, and a power supply module. The outputs of the temperature sensor, smoke sensor, combustible gas concentration detection unit, current transformer, and voltage transformer are respectively connected to the input of the multiplexer. The output of the multiplexer is connected to the input of the signal processing module. The output of the signal processing module is connected to the input of the analog-to-digital converter. The output of the analog-to-digital converter is connected to the input of the microcontroller module. The output of the image acquisition module is connected to the input of the microcontroller module. The output of the positioning module is connected to the input of the microcontroller module. The outputs of the microcontroller module are respectively connected to the inputs of the voice broadcast module, fire alarm module, and maintenance call module. The microcontroller module is connected to the HDMI interface circuit via the HDMI interface chip control unit. The power supply module is connected to the microcontroller module to provide the required power.

2. The integrated electrical fire monitoring system according to claim 1, characterized in that: The signal processing module includes a sensor signal conditioning circuit, a current signal conditioning circuit, a voltage signal conditioning circuit, a voltage divider follower filter circuit, and an A / D converter. The multiplexer switch is connected to the microcontroller module in sequence through the sensor signal conditioning circuit, the current signal conditioning circuit, the voltage signal conditioning circuit, the voltage divider follower filter circuit, and the A / D converter.

3. The integrated electrical fire monitoring system according to claim 1, characterized in that: The image acquisition module includes a CMOS image sensor, an input FIFO module, a DDR controller, an image parameter calculation module, a DDR2 SDRAM, and an output FIFO module. The output of the CMOS image sensor is connected to the input of the input FIFO module, the output of the input FIFO module is connected to the input of the DDR2 SDRAM, the output of the DDR2 SDRAM is connected to the input of the output FIFO module, the output of the image parameter calculation module is also connected to the input of the DDR2 SDRAM through the DDR controller, and the output of the output FIFO module is connected to the input of the main control module.

4. The integrated electrical fire monitoring system according to claim 2, characterized in that: The sensor signal conditioning circuit includes an analog signal input terminal, resistors R1 and R2, capacitor C1, and operational amplifier U1. The analog signal input terminal is connected to one end of resistor R1 and one end of resistor R2. The other end of resistor R2 is connected to one end of capacitor C1. The other end of capacitor C1 is connected to the other end of resistor R1 and the positive input terminal of operational amplifier U1. The negative input terminal of operational amplifier U1 is connected to the output terminal of operational amplifier U1.

5. The integrated electrical fire monitoring system according to claim 2, characterized in that: The voltage signal conditioning circuit includes a voltage signal input terminal, resistors R3, R4, and R5, capacitor C2, and operational amplifier U2. The voltage signal input terminal is connected to one end of resistor R3. The other end of resistor R3 is connected to one end of resistor R4 and one end of resistor R5. The other end of resistor R5 is connected to one end of capacitor C2. The other end of capacitor C2 is connected to the other end of resistor R4 and the positive input terminal of operational amplifier U1. The negative input terminal of operational amplifier U2 is connected to the output terminal of operational amplifier U2.

6. The integrated electrical fire monitoring system according to claim 2, characterized in that: The voltage divider follower filter circuit includes operational amplifier U3, resistor R11, resistor R12, operational amplifier U4, resistor R13, and capacitor C7. The output terminal of operational amplifier U3 is connected to one end of resistor R12. The other end of resistor R12 is connected to one end of resistor R11 and the positive input terminal of operational amplifier U4. The output terminal of operational amplifier U4 is connected to one end of resistor R13. The other end of resistor R13 is connected to one end of capacitor C7 and the A / D conversion unit. The other end of capacitor C7 is grounded. The other end of resistor R11 is connected to the current signal conditioning circuit.

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