Main and standby power detection and automatic switching circuit of fire-fighting power supply

Abstract

The main and standby power detection and automatic switching circuit comprises a main power supply module, a standby power supply module, a main power voltage detection module, a standby power voltage detection module, a charging control and main and standby power switching module and a main control module, the input end of the main power voltage detection module is connected with the output end of the main power supply module to detect the output voltage of the main power supply module, and the output end of the main power voltage detection module is connected with one I / O port of the main control module to send the detected output voltage of the main power supply module to the main control module. The input end of the main power supply module is connected with commercial power; the input end of the standby power voltage detection module is connected with the output end of the standby power supply module so as to detect the output voltage of the standby power supply module, and the output end of the standby power voltage detection module is connected with the other I / O port of the main control module so as to send the detected output voltage of the standby power supply module to the main control module.

Description

Technical Field

[0001] The utility model relates to the technical field of circuits, in particular to a fire-fighting power supply main and standby power detection and automatic switching circuit. Background Art

[0002] The fire host needs to work stably and continuously, so the internal power supply is an important part to ensure normal operation. Therefore, in addition to the mains power supply, the fire host is generally equipped with a battery as a backup power supply.

[0003] The existing fire host power supply generally adopts dual power supply of 220V (±10%) mains power + 24V battery. The mains power is stepped down by the power frequency transformer and then converted into DC voltage by the rectifier circuit for power supply. The mains power supply is used as the main power supply. When the main power fails, it automatically switches to the battery power supply to ensure the continuous operation of the fire host.

[0004] However, the existing power supply design circuit of the fire host is relatively complex, involving many components, and the mains input range is relatively small.

[0005] Therefore, it is necessary to design a fire power supply main and standby power detection and automatic switching circuit to solve the problems existing in the prior art. Utility Model Content

[0006] The purpose of the utility model is to provide a fire power supply main and standby power detection and automatic switching circuit, which can effectively solve the above-mentioned technical problems existing in the prior art.

[0007] In order to achieve the above-mentioned purpose, an embodiment of the utility model provides a fire power supply main and standby power detection and automatic switching circuit, which includes a main power supply module, a standby power supply module, a main power voltage detection module, a standby power voltage detection module, a charging control and main and standby power switching module, and a main control module;

[0008] The input end of the main power voltage detection module is connected to the output end of the main power supply module to detect the output voltage of the main power supply module, the output end of the main power voltage detection module is connected to an I / O port of the main control module to send the detected output voltage of the main power supply module to the main control module, and the input end of the main power supply module is connected to the main power supply; the input end of the backup power voltage detection module is connected to the output end of the backup power supply module to detect the output voltage of the backup power supply module, the output end of the backup power voltage detection module is connected to another I / O port of the main control module to send the detected output voltage of the backup power supply module to the main control module, the backup power supply module is a battery, and the rated voltage of the battery is 24Vdc;

[0009] The charging control and main-standby power switching module includes a first input / output terminal, a second input / output terminal and a controlled terminal, wherein the first input / output terminal, the second input / output terminal and the controlled terminal are respectively connected to the output terminal of the main power supply module, the output terminal of the backup power supply module and the control instruction output terminal of the main control module; the charging control and main-standby power switching module also includes a first diode, a second diode, a first fuse, a third diode, a fourth diode, a second fuse, a first light-emitting diode, a first resistor, a second resistor, a first capacitor, a third resistor, a first triode, a fifth diode, a relay, a fourth resistor and a fifth resistor; one end of the first diode and the second diode connected in parallel is connected to the first input / output terminal, and the other end is connected to one end of the first fuse, and the other end of the first fuse is connected to a 24V voltage; one end of the third diode and the fourth diode connected in parallel is connected to the The second input / output end, the other end of which is connected to one end of the first fuse; one end of the first resistor is connected to the controlled end, and the other end is connected to the base of the first transistor, the emitter of the first transistor is grounded, the collector of the first transistor is connected to pin 1 of the coil of the relay through the fifth diode on the one hand, and directly connected to pin 2 of the coil of the relay on the other hand, and pin 1 of the coil of the relay is connected to a 5V voltage; the input end of the first light-emitting diode is connected to the controlled end, and the output end is connected to the emitter of the first transistor through the second resistor; the first capacitor and the third resistor are connected in parallel and connected between the base and the emitter of the first transistor; one end of the fourth resistor and the fifth resistor in parallel is connected to pin 3 of the switch of the relay, and the other end is connected to one end of the third diode and the fourth diode in parallel, and pin 4 of the switch of the relay is connected to the 24V voltage.

[0010] As an improvement of the above solution, the main power supply module is a 24V 100W Mean Well rectifier module. The input voltage range of the main power supply module is 100-240Vac 50 / 60hz. The output voltage of the main power supply module can be adjusted to 27.6V, and the output end is connected to the CN5 port of the fire host board.

[0011] As an improvement of the above solution, the backup power supply module is a battery composed of two 12Vdc 7ah lead-acid batteries connected in series, with a rated voltage of 24Vdc, connected to the CN7 port of the fire host board.

[0012] As an improvement of the above solution, the main power voltage detection module includes a second capacitor, a third capacitor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a sixth diode, a seventh diode, a tenth resistor, an eleventh resistor, a twelfth resistor, a fourth capacitor, a first comparator, a thirteenth resistor and a fourteenth resistor; one end of the second capacitor, the sixth resistor and the seventh resistor is connected as the input end of the main power voltage detection module, the other ends of the second capacitor, the sixth resistor and the seventh resistor are connected as a common end and connected to one end of the third capacitor, the eighth resistor and the ninth resistor, and the other ends of the third capacitor, the eighth resistor and the ninth resistor are grounded; the sixth diode and the seventh diode are connected in series After being connected in parallel, they are connected between the 5V voltage and the ground, and the connection point of the sixth diode and the seventh diode is connected to the common end; one end of the tenth resistor is connected to the negative phase access terminal of the first comparator, and the other end is connected to the 5V voltage; one end of the eleventh resistor, the twelfth resistor and the fourth capacitor after being connected in parallel is connected to the negative phase access terminal of the first comparator, and the other end is grounded; the positive phase access terminal of the first comparator is connected to the common end; the power supply terminal of the first comparator is connected to the 5V voltage, the grounding terminal is grounded, the output terminal is connected to the 5V voltage through the thirteenth resistor on the one hand, and is connected to one end of the fourteenth resistor on the other hand, and the other end of the fourteenth resistor serves as the output end of the main power voltage detection module.

[0013] As an improvement of the above scheme, the backup power voltage detection module includes a fifteenth resistor and a sixteenth resistor in series, a seventeenth resistor and an eighteenth resistor in series, an eighth diode and a ninth diode in series, a tenth diode and an eleventh diode in series, a second comparator, a fifth capacitor and a nineteenth resistor in parallel, a sixth capacitor and a twentieth resistor in parallel, a twenty-first resistor, a seventh capacitor and a twenty-second resistor in parallel, a third comparator, a twenty-third resistor, an eighth capacitor, and a twelfth diode and a thirteenth diode in series; one end of the fifteenth resistor and the sixteenth resistor in series is connected as the input end of the backup power voltage detection module, and the other end is connected to the connection point of the eighth diode and the ninth diode and the positive phase input end of the second comparator; one end of the seventeenth resistor and the eighteenth resistor in series is grounded, and the other end is connected to the connection point of the tenth diode and the eleventh diode and the negative phase input end of the second comparator; one end of the fifth capacitor and the nineteenth resistor in parallel is connected to the second comparator. positive phase input terminal, and the other end is grounded; one end of the sixth capacitor and the twentieth resistor connected in parallel is connected to the negative phase input terminal of the second comparator, and the other end is connected to the output terminal of the second comparator, the power supply terminal of the second comparator is connected to a 5V voltage, and the ground terminal is grounded; the output terminal of the second comparator is connected to the positive phase input terminal of the third comparator through the twenty-first resistor; one end of the seventh capacitor and the twenty-second resistor connected in parallel is connected to the positive phase input terminal of the third comparator, and the other end is grounded; the negative phase input terminal of the third comparator is connected to the output terminal of the third comparator; the output terminal of the third comparator is connected to one end of the twenty-third resistor, and the other end of the twenty-third resistor is simultaneously connected to one end of the eighth capacitor, the connection point of the twelfth diode and the thirteenth diode, the other end of the eighth capacitor is grounded, one end of the twelfth diode and the thirteenth diode connected in series is connected to a 5V voltage, and the other end is grounded; the other end of the twenty-third resistor is also used as the output terminal of the backup power voltage detection module.

[0014] As an improvement of the above solution, the main control module adopts a control chip with MCU-S9KEAZ128AMLH as the core.

[0015] Compared with the prior art, the fire protection power supply main and standby power detection and automatic switching circuit provided by the embodiment of the utility model realizes the technical effects of wide voltage input of the main power supply, real-time detection of abnormal power failure of the main and standby power supplies, and seamless switching of the main and standby power supplies, wherein:

[0016] 1. Wide voltage input: Mean Well rectifier module has a wide input range, 100-240Vac 50 / 60hz.

[0017] 2. Real-time detection of main and backup power failures: continuous main power voltage and backup power voltage, when the main power voltage is lower than 22V, it is judged as a main power failure; when the backup power voltage is lower than 22V, it is judged as a backup power failure.

[0018] 3. Seamless switching between main and backup power: The main power voltage is adjusted to 27.6V (the main power supply has its own adjustment function), and the maximum voltage of the backup power is controlled to be no more than 26.8V when fully charged. The anti-reverse diodes are connected in series to supply power to the subsequent loads. Since the output voltage of the main power is higher than the backup power voltage, the load will give priority to the power provided by the main power, and the main power output will not be reversed to the backup power. When the main power fails, the main power output stops, and the voltage is lower than the backup power voltage. The backup power output anti-reverse diode is immediately turned on to provide power to the load, and the load will not be powered off. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the implementation mode will be briefly introduced below. Obviously, the drawings described below are only some implementation modes of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is a functional module structure diagram of a fire power supply main and standby power detection and automatic switching circuit provided by an embodiment of the utility model.

[0021] Figure 2 It is a circuit structure diagram of a main and standby power detection and automatic switching circuit for a fire power supply and a main and standby power switching module provided by an embodiment of the utility model.

[0022] Figure 3 The utility model provides a circuit structure diagram of a main power supply module of a fire power supply main and standby power detection and automatic switching circuit.

[0023] Figure 4 The utility model provides a circuit structure diagram of a backup power supply module of a fire power supply main and backup power detection and automatic switching circuit.

[0024] Figure 5 The utility model provides a circuit structure diagram of a main power voltage detection module of a fire power supply main and standby power detection and automatic switching circuit.

[0025] Figure 6 The utility model provides a circuit structure diagram of a backup power voltage detection module of a fire power supply main backup power detection and automatic switching circuit.

[0026] Figure 7 It is a chip schematic diagram of a main control module of a fire power supply main and standby power detection and automatic switching circuit provided by an embodiment of the utility model. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0028] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0029] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0030] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or can communicate with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] refer to Figure 1 The embodiment of the utility model provides a fire power supply main and backup power detection and automatic switching circuit, including a main power supply module 1, a backup power supply module 2, a main power voltage detection module 3, a backup power voltage detection module 4, a charging control and main and backup power switching module 5, and a main control module 6.

[0032] Among them, the input end of the main power voltage detection module 3 is connected to the output end of the main power supply module 1 to detect the output voltage of the main power supply module 1, and the output end of the main power voltage detection module 3 is connected to an I / O port of the main control module 6 (for example, I / O port No. 19, the specific I / O port is based on the definition in the program) to send the detected output voltage of the main power supply module 1 (output signal V_MWLow input) to the main control module 6, and the input end of the main power supply module 1 is connected to the mains.

[0033] The input end of the backup power voltage detection module 4 is connected to the output end of the backup power supply module 2 to detect the output voltage of the backup power supply module 2. The output end of the backup power voltage detection module 4 is connected to another I / O port of the main control module 6 (for example, I / O port 32, the specific I / O port is subject to the definition in the program) to send the detected output voltage of the backup power supply module (output signal AD-U1-BAT) to the main control module 6. The backup power supply module 2 is a battery, and the rated voltage of the battery is 24Vdc.

[0034] Combination Figure 1 and Figure 2 The charging control and main-backup power switching module 5 includes a first input / output terminal, a second input / output terminal and a controlled terminal, and the first input / output terminal, the second input / output terminal and the controlled terminal are respectively connected to the output terminal MWout of the main power supply module 1, the output terminal Battery+ of the backup power supply module 2 and the control instruction output terminal Charging relay out of the main control module 6.

[0035] Specifically, the charging control and main-standby power switching module 5 also includes a first diode D1, a second diode D2, a first fuse F1, a third diode D3, a fourth diode D4, a second fuse F2, a first light-emitting diode LED1, a first resistor R1, a second resistor R2, a first capacitor C1, a third resistor R3, a first transistor Q1, a fifth diode D5, a relay RY10, a fourth resistor R4 and a fifth resistor R5.

[0036] Among them, one end of the first diode D1 and the second diode D2 connected in parallel is connected to the first input / output end, and the other end is connected to one end of the first fuse F1, and the other end of the first fuse F1 is connected to a 24V voltage; one end of the third diode D3 and the fourth diode D4 connected in parallel is connected to the second input / output end through the second fuse F2, and the other end is connected to one end of the first fuse F1; one end of the first resistor R1 is connected to the controlled end, and the other end is connected to the base of the first transistor D1, the emitter of the first transistor D1 is grounded, and the collector of the first transistor D1 is connected to the coil of the relay RY10 through the fifth diode D5. Pin 1, on the other hand, is directly connected to pin 2 of the coil of the relay RY10, and pin 1 of the coil of the relay RY10 is connected to a 5V voltage; the input end of the first light-emitting diode LED1 is connected to the controlled end, and the output end is connected to the emitter of the first transistor D1 through the second resistor R2; the first capacitor C1 and the third resistor R3 are connected in parallel and connected between the base and the emitter of the first transistor D1; one end of the fourth resistor R4 and the fifth resistor R5 are connected in parallel to pin 3 of the switch of the relay RY10, and the other end is connected to one end of the third diode D3 and the fourth diode D4 are connected in parallel, and pin 4 of the switch of the relay RY10 is connected to the 24V voltage.

[0037] Further, combined with Figure 1 and Figure 3 The main power supply module 1 is a 24V 100W Mean Well rectifier module. The input voltage range of the main power supply module 1 is 100-240Vac 50 / 60hz. The output voltage of the main power supply module 1 can be adjusted to 27.6V. The output end is connected to the CN5 port of the fire host board, and the output is defined as MWout / GND.

[0038] Further, combined with Figure 1 and Figure 4 The backup power supply module 2 is a battery composed of two 12Vdc 7ah lead-acid batteries connected in series, with a rated voltage of 24Vdc, connected to the CN7 port of the fire host board, and the output is defined as Battery+ / GND.

[0039] Further, combined with Figure 1 and Figure 5 The main power voltage detection module 3 includes a second capacitor C2, a third capacitor C3, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a sixth diode D6, a seventh diode D7, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a fourth capacitor C4, a first comparator U1A, a thirteenth resistor R13 and a fourteenth resistor R14.

[0040] Among them, one end of the second capacitor C2, the sixth resistor R6 and the seventh resistor R7 is connected as the input end of the main power voltage detection module 3, the other ends of the second capacitor C2, the sixth resistor R6 and the seventh resistor R7 are connected as a common end and connected to one end of the third capacitor C3, the eighth resistor R8 and the ninth resistor R9, and the other ends of the third capacitor C3, the eighth resistor R8 and the ninth resistor R9 are grounded; the sixth diode D6 and the seventh diode D7 are connected in series between the 5V voltage and the ground, and the connection point of the sixth diode D6 and the seventh diode D7 is connected to the common end; one end of the tenth resistor R10 The first comparator U1A has a first end connected to the negative phase access terminal of the first comparator U1A, and the other end is connected to the 5V voltage; the eleventh resistor R11, the twelfth resistor R12 and the fourth capacitor C4 are connected in parallel, one end is connected to the negative phase access terminal of the first comparator U1A, and the other end is grounded; the positive phase access terminal of the first comparator U1A is connected to the common terminal; the power supply terminal of the first comparator U1A is connected to the 5V voltage, the ground terminal is grounded, the output terminal is connected to the 5V voltage through the thirteenth resistor R13 on the one hand, and is connected to one end of the fourteenth resistor R14 on the other hand, and the other end of the fourteenth resistor R14 serves as the output terminal of the main power voltage detection module 3.

[0041] Further, combined with Figure 1 and Figure 6 The backup power voltage detection module 4 includes a fifteenth resistor R15 and a sixteenth resistor R16 connected in series, a seventeenth resistor R17 and an eighteenth resistor R18 connected in series, an eighth diode D8 and a ninth diode D9 connected in series, a tenth diode D10 and an eleventh diode D11 connected in series, a second comparator U2A, a fifth capacitor C5 and a nineteenth resistor R19 connected in parallel, a sixth capacitor C6 and a twentieth resistor R20 connected in parallel, a twenty-first resistor R21, a seventh capacitor C7 and a twenty-second resistor R22 connected in parallel, a third comparator U3A, a twenty-third resistor R23, an eighth capacitor C8, and a twelfth diode D12 and a thirteenth diode D13 connected in series.

[0042] Among them, one end of the fifteenth resistor R15 and the sixteenth resistor R16 connected in series is connected as the input end of the backup power voltage detection module 4, and the other end is connected to the connection point of the eighth diode D8 and the ninth diode D9 and the positive input end of the second comparator U2A; one end of the seventeenth resistor R17 and the eighteenth resistor R18 connected in series is grounded, and the other end is connected to the connection point of the tenth diode D10 and the eleventh diode D11 and the negative input end of the second comparator U1A; one end of the fifth capacitor C5 and the nineteenth resistor R19 connected in parallel is connected to the positive input end of the second comparator U2A, and the other end is grounded; one end of the sixth capacitor C6 and the twentieth resistor R20 connected in parallel is connected to the negative input end of the second comparator U2A, and the other end is connected to the output end of the second comparator U2A, the power supply end of the second comparator U2A is connected to a 5V voltage, and the ground end is grounded; The output end of the second comparator U2A is connected to the positive phase input end of the third comparator U3A through the twenty-first resistor R21; one end of the seventh capacitor C7 and the twenty-second resistor R22 connected in parallel is connected to the positive phase input end of the third comparator U3A, and the other end is grounded; the negative phase input end of the third comparator U3A is connected to the output end of the third comparator U3A; the output end of the third comparator U3A is connected to one end of the twenty-third resistor R23, and the other end of the twenty-third resistor R23 is simultaneously connected to one end of the eighth capacitor C8, the connection point of the twelfth diode D12 and the thirteenth diode D13, the other end of the eighth capacitor C8 is grounded, and one end of the twelfth diode D12 and the thirteenth diode D13 connected in series is connected to a 5V voltage, and the other end is grounded; the other end of the twenty-third resistor R23 also serves as the output end of the backup power voltage detection module 4.

[0043] Further, combined with Figure 1 and Figure 6 The main control module 6 adopts a control chip with MCU-S9KEAZ128AMLH as the core.

[0044] Next, combine Figure 1 to Figure 7 , the working principle and working process of a fire power supply main and standby power detection and automatic switching circuit provided by the utility model are described in detail.

[0045] Charging logic: The normal voltage of the backup battery is 24V, and the preset charging completion voltage is 26.8V. When the main power and the backup power are connected normally, the signal of the main power voltage detection module 3 and the backup power voltage detection module 4 is transmitted to the main control module 6. When the main control module 6 receives that the main power is normal and the backup power voltage is lower than 25V, it sends a charging instruction to the charging control and main-backup power switching module 5, so that the relay RY10 of the charging control and main-backup power switching module 5 is energized, and the main power charges the backup battery through the relay RY10 and the fourth and fifth resistors R4 / R5. When the main control module 6 receives that the backup power voltage reaches 26.8V for 5S, it stops sending charging instructions to the charging control and main-backup power switching module 5, and the relay RY10 is disconnected, and charging stops.

[0046] Automatic switching between main and backup power: When the main power is off, the voltage will drop rapidly. When the main power voltage is lower than the backup power voltage, due to the diode characteristics, the first and second diodes D1 / D2 will be quickly turned off, and the third and fourth diodes D3 / D4 will be quickly turned on. When the main power is restored and the voltage exceeds the backup power voltage, the first and second diodes D1 / D2 will be turned on again, and the third and fourth diodes D3 / D4 will be turned off.

[0047] Main power failure detection: When the main control module 6 receives the main power voltage detected by the main power voltage detection module 3 and the main power voltage is lower than 22V, it is judged as a main power failure, charging is stopped, and a main power failure signal is sent to the outside.

[0048] Backup power failure detection: During the charging phase, when the main control module 6 receives the backup power voltage detected by the backup power voltage detection module 4 and it is higher than 26.8V for more than 5S, the main control module 6 stops sending charging instructions to the charging control and main-backup power switching module 5, and the relay RY10 is disconnected. At this time, if the backup power has been disconnected, the backup power voltage will drop rapidly. The backup power voltage detection module 4 detects that the backup power voltage is rapidly dropping. If the voltage is lower than 22V for more than 5S, the main control module 6 receives the signal from the backup power voltage detection module 4 and determines that it is a backup power failure, and sends a backup power failure signal to the outside. During the non-charging phase, the backup power is disconnected, and the backup power voltage will drop rapidly. The backup power voltage detection module 4 detects that the backup power voltage is rapidly dropping. If the voltage is lower than 22V for more than 5S, the main control module 6 receives the signal from the backup power voltage detection module 4 and determines that it is a backup power failure, and sends a backup power failure signal to the outside.

[0049] In summary, the utility model provides a fire power supply main and standby power detection and automatic switching circuit that uses a rectifier module instead of a power frequency transformer step-down solution. The first input voltage range is larger and supports the use of mains with different voltage levels. Automatic switching of main and standby power, simple logic, no need for program control, few devices, and low cost, thus bringing the following technical effects: 1. Mains wide voltage input: Meanwell rectifier module has a wide input range of 100-240Vac 50 / 60hz. 2. Real-time detection of whether the main and standby power are powered off: continuous main power voltage and standby power voltage, when the main power voltage is lower than 22V, it is judged as a main power failure; when the standby power voltage is lower than 22V, it is judged as a standby power failure. 3. Seamless switching of main and standby power: the main power voltage is adjusted to 27.6V (the main power supply has its own adjustment function), and the voltage of the standby power is controlled to be no more than 26.8V when it is fully charged. Each anti-reverse diode is connected in series to supply power to the subsequent load. Because the main power output voltage is higher than the standby power voltage, the load will give priority to the power provided by the main power, and the main power output will not be reversed to the standby power. When the main power fails, the main power output stops, and the voltage is lower than the backup power voltage. The backup power output anti-reverse diode immediately turns on to provide power to the load, and the load will not be powered off.

[0050] The above disclosures are only some preferred embodiments of the present invention, which certainly cannot be used to limit the scope of the present invention. A person skilled in the art can understand that all or part of the processes of the above embodiments and equivalent changes made according to the claims of the present invention still fall within the scope of the present invention.

Claims

1. A fire power supply main and standby power detection and automatic switching circuit, characterized in that: It includes a main power supply module, a backup power supply module, a main power voltage detection module, a backup power voltage detection module, a charging control and main and backup power switching module, and a main control module; The input end of the main power voltage detection module is connected to the output end of the main power supply module to detect the output voltage of the main power supply module, the output end of the main power voltage detection module is connected to an I / O port of the main control module to send the detected output voltage of the main power supply module to the main control module, and the input end of the main power supply module is connected to the main power supply; the input end of the backup power voltage detection module is connected to the output end of the backup power supply module to detect the output voltage of the backup power supply module, the output end of the backup power voltage detection module is connected to another I / O port of the main control module to send the detected output voltage of the backup power supply module to the main control module, the backup power supply module is a battery, and the rated voltage of the battery is 24Vdc; The charging control and main-backup power switching module includes a first input / output terminal, a second input / output terminal and a controlled terminal, wherein the first input / output terminal, the second input / output terminal and the controlled terminal are respectively connected to the output terminal of the main power supply module, the output terminal of the backup power supply module and the control instruction output terminal of the main control module; the charging control and main-backup power switching module also includes a first diode, a second diode, a first fuse, a third diode, a fourth diode, a second fuse, a first light-emitting diode, a first resistor, a second resistor, a first capacitor, a third resistor, a first triode, a fifth diode, a relay, a fourth resistor and a fifth resistor; the first diode and the second diode are connected in parallel. One end of the third diode and the fourth diode connected in parallel is connected to the second input / output end through the second fuse, and the other end is connected to one end of the first fuse; one end of the first resistor is connected to the controlled end, and the other end is connected to the base of the first transistor, the emitter of the first transistor is grounded, the collector of the first transistor is connected to the pin 1 of the coil of the relay through the fifth diode on the one hand, and is directly connected to the pin 2 of the coil of the relay on the other hand, and the pin 1 of the coil of the relay is connected to the 5V voltage; The input end of the first light-emitting diode is connected to the controlled end, and the output end is connected to the emitter of the first transistor through the second resistor; the first capacitor and the third resistor are connected in parallel and connected between the base and the emitter of the first transistor; one end of the fourth resistor and the fifth resistor in parallel is connected to pin 3 of the relay switch, and the other end is connected to one end of the third diode and the fourth diode in parallel, and pin 4 of the relay switch is connected to the 24V voltage.

2. The fire power supply main and standby power detection and automatic switching circuit according to claim 1 is characterized in that: The main power supply module is a 24V 100W Mean Well rectifier module. The input voltage range of the main power supply module is 100-240Vac50 / 60hz. The output voltage of the main power supply module can be adjusted to 27.6V, and the output end is connected to the CN5 port of the fire host board.

3. The fire power supply main and standby power detection and automatic switching circuit according to claim 1 is characterized in that: The backup power supply module is a battery composed of two 12Vdc 7ah lead-acid batteries connected in series, with a rated voltage of 24Vdc, connected to the CN7 port of the fire host board.

4. The fire power supply main and standby power detection and automatic switching circuit according to claim 1 is characterized in that: The main power voltage detection module includes a second capacitor, a third capacitor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a sixth diode, a seventh diode, a tenth resistor, an eleventh resistor, a twelfth resistor, a fourth capacitor, a first comparator, a thirteenth resistor and a fourteenth resistor; one end of the second capacitor, the sixth resistor and the seventh resistor is connected as an input end of the main power voltage detection module, the other ends of the second capacitor, the sixth resistor and the seventh resistor are connected as a common end and connected to one end of the third capacitor, the eighth resistor and the ninth resistor, and the other ends of the third capacitor, the eighth resistor and the ninth resistor are grounded; the sixth diode and the seventh diode are connected in series to 5V voltage and ground, and the connection point of the sixth diode and the seventh diode is connected to the common end; one end of the tenth resistor is connected to the negative phase access terminal of the first comparator, and the other end is connected to the 5V voltage; one end of the eleventh resistor, the twelfth resistor and the fourth capacitor in parallel is connected to the negative phase access terminal of the first comparator, and the other end is grounded; the positive phase access terminal of the first comparator is connected to the common end; the power supply terminal of the first comparator is connected to the 5V voltage, the ground terminal is grounded, the output terminal is connected to the 5V voltage through the thirteenth resistor on the one hand, and is connected to one end of the fourteenth resistor on the other hand, and the other end of the fourteenth resistor serves as the output end of the main power voltage detection module.

5. The fire power supply main and standby power detection and automatic switching circuit according to claim 1 is characterized in that: The backup power voltage detection module includes a fifteenth resistor and a sixteenth resistor connected in series, a seventeenth resistor and an eighteenth resistor connected in series, an eighth diode and a ninth diode connected in series, a tenth diode and an eleventh diode connected in series, a second comparator, a fifth capacitor and a nineteenth resistor connected in parallel, a sixth capacitor and a twentieth resistor connected in parallel, a twenty-first resistor, a seventh capacitor and a twenty-second resistor connected in parallel, a third comparator, a twenty-third resistor, an eighth capacitor, and a twelfth diode and a thirteenth diode connected in series; one end of the fifteenth resistor and the sixteenth resistor connected in series is connected as the input end of the backup power voltage detection module, and the other end is connected to the connection point of the eighth diode and the ninth diode and the positive phase input end of the second comparator; one end of the seventeenth resistor and the eighteenth resistor connected in series is grounded, and the other end is connected to the connection point of the tenth diode and the eleventh diode and the negative phase input end of the second comparator; one end of the fifth capacitor and the nineteenth resistor connected in parallel is connected to the positive phase input end of the second comparator , the other end is grounded; one end of the sixth capacitor and the twentieth resistor connected in parallel is connected to the negative phase input end of the second comparator, and the other end is connected to the output end of the second comparator, the power supply end of the second comparator is connected to a 5V voltage, and the ground end is grounded; the output end of the second comparator is connected to the positive phase input end of the third comparator through the twenty-first resistor; one end of the seventh capacitor and the twenty-second resistor connected in parallel is connected to the positive phase input end of the third comparator, and the other end is grounded; the negative phase input end of the third comparator is connected to the output end of the third comparator; the output end of the third comparator is connected to one end of the twenty-third resistor, and the other end of the twenty-third resistor is simultaneously connected to one end of the eighth capacitor, the connection point of the twelfth diode and the thirteenth diode, the other end of the eighth capacitor is grounded, one end of the twelfth diode and the thirteenth diode connected in series is connected to a 5V voltage, and the other end is grounded; the other end of the twenty-third resistor is also used as the output end of the backup power voltage detection module.

6. The fire power supply main and standby power detection and automatic switching circuit according to claim 1 is characterized in that: The main control module adopts a control chip with MCU-S9KEAZ128AMLH as the core.

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