A power-on self-test device for an electrical appliance and an electrical appliance

Abstract

The present invention discloses a power-on self-checking device for an electrical equipment and the electrical equipment. The device includes: a power supply unit, which supplies power to an isolation unit and a switch unit when the electrical equipment is powered on; the isolation unit takes a power supply signal as a first signal to be measured and a signal at a test point as a second signal to be measured, and tests whether a short-circuit fault occurs between the first signal to be measured and the second signal to be measured. If no short-circuit fault occurs, it outputs a first isolation signal; if a short-circuit fault occurs, it outputs a second isolation signal; the switch unit, upon receiving the first isolation signal, controls the main power supply of the electrical equipment to supply power to the electrical equipment; upon receiving the second isolation signal, controls the main power supply of the electrical equipment not to supply power to the electrical equipment. With this solution, by enabling the electrical equipment to perform self-checking when the electrical equipment is powered on, and allowing the electrical equipment to be powered on and operate only when the self-checking is passed, it can at least improve the safety of the electrical equipment itself.

Description

Technical Field

[0001] The present invention belongs to the technical field of power-on control, and particularly relates to a power-on self-checking device for an electrical device and an electrical device, and more particularly to a power-on hardware self-checking circuit for an electrical device and an electrical device having the power-on hardware self-checking circuit. Background Art

[0002] With the development of technology, various electrical devices are filled in various occasions. The short-circuit operation of a device (such as an electrical device) will pose great risks. Especially for large devices, there will be situations of burning or even explosion, seriously endangering the safety of personal and property.

[0003] The above content is only used to assist in understanding the technical solution of the present invention, and does not represent an admission that the above content is prior art. Summary of the Invention

[0004] The purpose of the present invention is to provide a power-on self-checking device for an electrical device and an electrical device, so as to solve the problem that the electrical device may operate in a short circuit, which poses a great potential safety hazard. Thus, by enabling the electrical device to perform self-checking when the electrical device is powered on, and allowing the electrical device to be powered on only when the self-check is passed, at least the safety of the electrical device itself can be improved.

[0005] In a power-on self-checking device for an electrical device provided by the present invention, the electrical device has N power consumption networks, where N is a positive integer; the current power consumption network to be tested among the N power consumption networks is denoted as the current power consumption network; the power-on self-checking device of the electrical device includes: a power supply unit, an isolation unit, and a switch unit; wherein, the power supply unit is configured to supply power to the isolation unit and the switch unit when the electrical device is powered on; the isolation unit is configured to use a power supply signal provided by the power supply unit as a first signal to be tested, and use the signal at any test point in the current power consumption network as a second signal to be tested, and test whether a short-circuit fault occurs between the first signal to be tested and the second signal to be tested: if no short-circuit fault occurs between the first signal to be tested and the second signal to be tested, output a first isolation signal; if a short-circuit fault occurs between the first signal to be tested and the second signal to be tested, output a second isolation signal; the switch unit is configured to control the main power supply of the electrical device to supply power to the electrical device when receiving the first isolation signal; and control the main power supply of the electrical device not to supply power to the electrical device when receiving the second isolation signal.

[0006] In some embodiments, the power supply includes: a separately provided first weak power supply, or a second weak power supply obtained by converting the main power supply of the electrical device.

[0007] In some embodiments, the isolation unit includes a voltage conversion module and an optocoupler module. Among them, the voltage conversion module is disposed at the output end of the power supply unit and outputs two power supply signals. The two power supply signals include a positive power supply signal and a negative power supply signal. The positive power supply signal is input to the anode of the diode side in the optocoupler module. The second signal to be measured is input to the cathode of the diode side in the optocoupler module. The negative power supply signal serves as the first signal to be measured. The power supply unit is further connected to the collector of the transistor side in the optocoupler module. The emitter of the transistor side in the optocoupler module is connected to the switch unit.

[0008] In some embodiments, the isolation unit further includes a first current limiting module and a second current limiting module. Among them, the first current limiting module is disposed between the positive power supply signal and the anode of the diode side in the optocoupler module. The second current limiting module is disposed between the power supply unit and the collector of the transistor side in the optocoupler module.

[0009] In some embodiments, the switch unit includes a first switch tube module and a second switch tube module. Among them, the emitter of the transistor side in the optocoupler module is connected to the control end of the first switch tube module. The power supply unit is further connected to the first connection end of the first switch tube module. The second connection end of the first switch tube module is connected to the control end of the second switch tube module. The first connection end of the second switch tube module is connected to the electrical device. The second connection end of the second switch tube module is connected to the main power supply of the electrical device.

[0010] In some embodiments, the first switch tube module includes a triode, and the triode is a PNP type triode. The second switch tube module includes a relay. The control end of the first switch tube module is the base of the triode. The first connection end of the first switch tube module is the emitter of the triode. The second connection end of the first switch tube module is the collector of the triode. The control end of the second switch tube module is the coil end of the relay. The first connection end of the second switch tube module is the first connection end of the normally open contact of the relay. The second connection end of the second switch tube module is the second connection end of the normally open contact of the relay.

[0011] In some embodiments, the switch unit further includes a delay module. The delay module is disposed between the power supply unit and the first connection end of the first switch tube module.

[0012] In some embodiments, an alarm module is further included. The alarm module is disposed at the emitter of the transistor side in the optocoupler module.

[0013] In some embodiments, it further includes: a third current limiting module; the third current limiting module is disposed between the emitter on the transistor side in the optocoupler module and the alarm module.

[0014] Matched with the above device, on the other hand, the present invention provides an electrical device, including: the power-on self-checking device of the electrical device described above.

[0015] Thus, in the solution of the present invention, by setting up a self-checking circuit for the electrical device, through this self-checking circuit, two test points of any power consumption network inside the electrical device are detected to determine whether there is a short circuit between the two test points of this power consumption network: if there is a short circuit, the power supply of this power consumption network is disconnected, if there is no short circuit, the power supply of this power consumption network is turned on. Thus, by making the electrical device perform self-checking when the electrical device is powered on, and only allowing the electrical device to operate after passing the self-checking, it can at least improve the safety of the electrical device itself.

[0016] Other features and advantages of the present invention will be described in the subsequent description, and part of them will be obvious from the description, or will be understood by implementing the present invention.

[0017] Next, through the drawings and embodiments, the technical solution of the present invention will be further described in detail. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic structural diagram of an embodiment of the power-on self-checking device of the electrical device of the present invention;

[0019] Figure 2 It is a schematic structural diagram of an embodiment of the power-on self-checking circuit. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] To make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0021] As the service life of the device increases, the device circuit will inevitably age, and the environment will also have many adverse factors on the device. Especially in some industrial application scenarios, the environment for the device is extremely harsh. Through conventional solutions such as dust prevention and heat dissipation to avoid environmental impacts, they will gradually fail over time, or due to the mistakes of operators, ultimately the following situations will occur:

[0022] (1) The natural aging of the equipment causes corrosion and damage to the cables and other connecting wires inside the equipment, resulting in short circuits that are difficult to detect through routine inspections.

[0023] (2) As far as developers are concerned, during the development and debugging phase, they may cause important network short circuits due to negligence, resulting in danger when power is turned on.

[0024] (3) In many applications, various conductive impurities are inevitably generated or the environment is extremely humid. When the protection of the equipment fails (dust and moisture proof), it will cause a short circuit in the internal circuit of the equipment, which will cause danger during the operation of the equipment.

[0025] (4) Misoperation by the equipment operator may result in incorrect line connection, which may cause a short circuit and create a dangerous situation.

[0026] (5) The equipment is sealed or the environment is crowded, making it difficult to inspect the inside of the equipment.

[0027] Short circuits are one of the most dangerous situations in equipment operation. Unknowingly powering a device that has experienced a short circuit can lead to serious consequences, especially for large equipment, resulting in significant losses. Hardware short circuits can be caused by a variety of factors, and many are difficult to detect through standard equipment inspections.

[0028] Before operating a device, it must be ensured that there are no short circuits in its wiring. This is often impossible to determine visually, and in many cases, operators are not equipped to perform this inspection. Therefore, the device must independently determine the internal wiring conditions. The present invention proposes a power-on hardware self-test solution, such as a power-on self-test device for electrical equipment.

[0029] According to an embodiment of the present invention, a power-on self-test device for an electrical device is provided. Figure 1 The structural schematic diagram of an embodiment of the device of the present invention is shown. The power-on self-test device of the electrical device may include: the electrical device has N power networks, N is a positive integer. The current power network to be tested among the N power networks is recorded as the current power network. The power-on self-test device of the electrical device includes: a power supply unit, an isolation unit and a switch unit. The power supply unit supplies power to the isolation unit and the switch unit respectively. The isolation unit is arranged at the front end of the switch unit. The switch unit is arranged between the electrical device and the main power supply of the electrical device.

[0030] Wherein, the power supply unit is configured to supply power to the isolation unit and the switch unit when the electrical device is powered on.

[0031] The isolation unit is configured to use a power supply signal provided by the power supply unit as a first signal to be measured, and use the signal at any test point in the current power consumption network as a second signal to be measured, and test whether a short - circuit fault occurs between the first signal to be measured and the second signal to be measured: If no short - circuit fault occurs between the first signal to be measured and the second signal to be measured, a first isolation signal is output. If a short - circuit fault occurs between the first signal to be measured and the second signal to be measured, a second isolation signal is output.

[0032] The switch unit is configured to, when receiving the first isolation signal, control the main power supply of the electrical device to supply power to the electrical device. When receiving the second isolation signal, control the main power supply of the electrical device not to supply power to the electrical device.

[0033] In the solution of the present invention, through a power - on hardware self - inspection scheme, it is checked whether there is a short - circuit at important positions before the device runs, so as to prohibit charging when there is a short - circuit, prevent device damage, and thus ensure the safety of the device and the operator. Thereby, the short - circuit operation situation caused by natural aging of the device is solved, and at least the safety of the electrical device itself can be improved. The R & D debugging risk caused by short - circuits is solved, and the development progress is prevented from being affected by short - circuit burning. The short - circuit operation situation caused by charged substances in the environment is solved. The short - circuit operation situation caused by misoperation of the operator is solved. It also solves the situation where it is impossible to check the internal situation of the device due to the surrounding conditions of the device not allowing it.

[0034] In some embodiments, the power supply includes: a separately provided first weak - current power supply, or a second weak - current power supply obtained by converting the main power supply of the electrical device. The first weak - current power supply and the second weak - current power supply can both be weak - current power supplies such as weak - current power supply VCC1, weak - current power supply VCC2, and weak - current power supply VCC3. That is to say, the weak - current power supplies VCC1, VCC2, and VCC3 can be provided by sharing one power supply, or of course they can be independent of each other. Sharing will reduce costs, and the power - on timing is consistent, which is more convenient for the delay control of the delay circuit.

[0035] In some embodiments, the isolation unit includes: a voltage conversion module and an optocoupler module. The voltage conversion module is, for example, a DC / DC isolation power supply. The optocoupler module is, for example, optocoupler OC1.

[0036] Among them, the voltage conversion module is arranged at the output end of the power supply unit and outputs two power supply signals. The two power supply signals include: a positive power supply signal and a negative power supply signal. The positive power supply signal is input to the anode of the diode side in the optocoupler module. The second signal to be measured is input to the cathode of the diode side in the optocoupler module. The negative power supply signal serves as the first signal to be measured.

[0037] The power supply unit is also connected to the collector on the transistor side of the optocoupler module. The emitter on the transistor side of the optocoupler module is connected to the switch unit.

[0038] Figure 2 It is a schematic structural diagram of an embodiment of the power-on self-checking circuit. In Figure 2 In the example shown, the weak power supply VCC1 is input to the DC / DC isolation power supply. The positive connection terminal of the DC / DC isolation power supply is connected to the anode of the diode side of the optocoupler OC1 via the current-limiting resistor R1. The negative connection terminal of the DC / DC isolation power supply is connected to the first signal to be measured (such as the signal to be measured 1). The second signal to be measured (such as the signal to be measured 2) is connected to the cathode of the diode side of the optocoupler OC1.

[0039] Among them, the first signal to be measured and the second signal to be measured can be two points to be measured of any power consumption network inside the electrical equipment.

[0040] For example: The first signal to be measured and the second signal to be measured can be two reference grounds in the device, such as the strong power ground and the weak power ground. The precondition for setting two reference grounds is that the two power supplies are isolated from each other. If they are not isolated from each other, there is no such thing as a short circuit between the grounds. Usually, for electrical safety and reducing interference, the grounds of the strong power and the weak power are isolated from each other.

[0041] Another example: The first signal to be measured and the second signal to be measured can be the power supply and the ground in the device.

[0042] Another example: The first signal to be measured and the second signal to be measured can be two power supplies in the device, such as the strong power supply, the weak power supply, and some power supplies required by the periphery of the CPU, etc.

[0043] Another example: The first signal to be measured and the second signal to be measured can be some input signals of the CPU and the ground. If the input signal terminal of the CPU is short-circuited to the ground, although this situation will not pose a risk, it makes the level of the input signal pin of the CPU always at a low level (because the ground is at a low level), causing the CPU to not work properly.

[0044] In some embodiments, the isolation unit further includes: a first current-limiting module and a second current-limiting module. The first current-limiting module, such as the current-limiting resistor R1. The second current-limiting module, such as the current-limiting resistor R2.

[0045] Among them, the first current-limiting module is arranged between the positive power supply signal and the anode of the diode side of the optocoupler module.

[0046] The second current-limiting module is arranged between the power supply unit and the collector on the transistor side of the optocoupler module.

[0047] In some embodiments, the switch unit includes: a first switch tube module and a second switch tube module. The first switch tube module is, for example, a PNP transistor Q1. The second switch tube module is, for example, a relay K1.

[0048] Wherein, the emitter of the transistor side in the optocoupler module is connected to the control end of the first switch tube module. The power supply unit is also connected to the first connection end of the first switch tube module. The second connection end of the first switch tube module is connected to the control end of the second switch tube module.

[0049] The first connection end of the second switch tube module is connected to the electrical device. The second connection end of the second switch tube module is connected to the main power supply of the electrical device.

[0050] In some embodiments, the first switch tube module includes: a triode, the triode is a PNP triode, such as a PNP transistor Q1. The second switch tube module includes: a relay, such as a relay K1.

[0051] The control end of the first switch tube module is the base of the triode. The first connection end of the first switch tube module is the emitter of the triode. The second connection end of the first switch tube module is the collector of the triode.

[0052] The control end of the second switch tube module is the coil end of the relay. The first connection end of the second switch tube module is the first connection end of the normally open contact of the relay. The second connection end of the second switch tube module is the second connection end of the normally open contact of the relay.

[0053] In Figure 2 In the example shown, the weak power supply VCC2 is connected to the collector of the transistor side of the optocoupler OC1 after passing through the current limiting resistor R2. The emitter of the transistor side of the optocoupler OC1 is connected to the anode of the short - circuit warning lamp D1 after passing through the current limiting resistor R3. The cathode of the short - circuit warning lamp D1 is grounded. The emitter of the transistor side of the optocoupler OC1 is also connected to the base of the PNP transistor Q1.

[0054] In Figure 2 In the example shown, the weak power supply VCC3 is connected to the emitter of the PNP transistor Q1 after passing through the delay circuit. The collector of the PNP transistor Q1 is connected to the control end of the relay K1. The second connection end of the normally open contact of the relay K1 is connected to the main power supply of the electrical device. The first connection end of the normally open contact of the relay K1 is connected to the power supply input end of the electrical device.

[0055] In some embodiments, the switch unit further includes: a delay module, such as a delay circuit.

[0056] The delay module is disposed between the power supply unit and the first connection end of the first switching tube module.

[0057] In some embodiments, it further includes: an alarm module, such as a short - circuit alarm lamp D1.

[0058] The alarm module is disposed at the emitter of the transistor side in the optocoupler module.

[0059] In some embodiments, it further includes: a third current - limiting module, such as a current - limiting resistor R3.

[0060] The third current - limiting module is disposed between the emitter of the transistor side in the optocoupler module and the alarm module.

[0061] As Figure 2 shown, the power - on self - test circuit includes: a DC / DC isolated power supply, current - limiting resistors R1, R2, R3, an optocoupler OC1, a relay K1, a PNP - type triode Q1, a delay circuit, a short - circuit alarm lamp D11, weak power supplies VCC1, VCC2, and VCC3. The weak power supplies VCC1, VCC2, and VCC3 can be the same weak power supply, such as 3V, 5V, etc., or different weak power supplies.

[0062] In the solution of the present invention, the hardware circuit of the power - on self - test circuit as Figure 2 shown is used for detecting the line short - circuit condition before the device is normally powered on. The specific usage process is as follows:

[0063] Process 1: After the device (such as an electrical device) is started, the weak power is turned on. The weak power (such as the weak power supply VCC1) passes through the DC / DC isolated power supply to convert the required first signal to be measured (such as the signal to be measured 1), and the current - limiting resistor R1 is used to limit the current magnitude input to the optocoupler OC1.

[0064] For example: The first signal to be measured is a point in the power - using network that needs to be detected. Connect this point to the negative pole of the DC / DC power supply as the reference ground of the power supply. If a short - circuit occurs between the signals to be measured 1 and 2, it is equivalent to the networks to which these two signals to be measured belong becoming one network. The DC / DC power supply and the diode of the optocoupler will form a loop through these two signals to be measured and output a voltage. When there is no short - circuit, these two signals will be isolated from each other (normally they are isolated from each other), and the above - mentioned loop will be in a short - circuit state.

[0065] Process 2: The power supply is connected to the anode of the light - emitting diode of the optocoupler OC1, and the second signal to be measured (such as the signal to be measured 2) is input to the cathode of the light - emitting diode of the optocoupler OC1.

[0066] Process 3: The collector of the triode at the output end of optocoupler OC1 is connected to a weak power supply (such as weak power supply VCC2). The emitter of the triode at the output end of optocoupler OC1 is connected to the base of PNP triode Q1 and the anode of short-circuit alarm lamp D1.

[0067] Process 4: Multiple second signals to be measured (such as signal to be measured 2) can be connected in parallel. For example, if the reference ground of the strong power is selected as the first signal to be measured, then the strong power supply can be used as the signal to be measured, or the weak ground or weak power supply can be used to detect whether there is a short circuit with the strong power supply at the same time. Diodes need to be added when used in parallel to ensure that the signals in parallel will not cause a short circuit due to the parallel detection operation.

[0068] When there is no short-circuit fault between the second signal to be measured (such as signal to be measured 2) and the first signal to be measured (such as signal to be measured 1), the triode at the back end of optocoupler OC1 is not conducting, the short-circuit alarm lamp D1 is not lit, the base of PNP triode Q1 is pulled low, PNP triode Q1 conducts, and after the delay set by the delay circuit, the weak power supply (such as weak power supply VCC3) supplies power to the control end of relay K1, relay K1 conducts, and the main power supply of the device normally supplies power to the device.

[0069] Among them, the characteristic of the PNP triode, generally speaking, is that the PNP triode cuts off when the base is at a high level and conducts when the base is at a low level. The reason for the pull-down is that the base of this triode is connected to the ground through a current-limiting resistor and a light-emitting diode, showing a low-level state.

[0070] Process 5: When a short-circuit fault occurs between the second signal to be measured (such as signal to be measured 2) and the first signal to be measured (such as signal to be measured 1), the diode at the front end of optocoupler OC1 conducts, the light-emitting diode inside optocoupler OC1 emits light, the phototransistor at the back end of optocoupler OC1 conducts, the short-circuit alarm lamp D1 emits light for alarm, the base of PNP triode Q1 is pulled high, PNP triode Q1 turns off, relay K1 does not conduct, and the device cannot be powered. Due to the existence of the delay circuit, relay K1 will not conduct directly when power is applied.

[0071] Among them, the base of PNP triode Q1 is pulled high because the photosensitive device of optocoupler OC1 conducts, and the weak power supply supplies power to the base of the PNP triode, showing a high-level state.

[0072] In related solutions, it is mostly a software + hardware joint processing mode, which means that the device CPU must be in the normal working mode because only in this way can it process signals and send instructions. However, if there is a short circuit in the CPU power supply part, it will still pose a danger, but the device cannot detect this risk. The power-on self-check circuit proposed in the solution of the present invention adopts a pure hardware mode, ensuring that the detection can be completed before the power supply required by the device is supplied, without the participation of the CPU, and is safer.

[0073] The solution of the present invention proposes a power-on self-checking solution for electrical equipment. Before power-on operation, weak electricity is provided by the power supply. When there is no short circuit, the self-checking circuit drives the relay to conduct and supply power to the equipment. When a short circuit occurs, the self-checking circuit does not drive the relay, preventing the equipment from being normally powered, and the alarm light is turned on to indicate the short circuit. Thus, it is possible to avoid short circuits caused by reasons such as human operation, equipment aging, and the environment, which may otherwise lead to equipment failures and personal and property losses after the equipment is powered on. The equipment can automatically check for internal short circuits, covering the blind spots of equipment inspection, and improving the reliability and safety of the equipment. It at least solves the hazards caused by short circuits during operation due to reasons such as human operation, equipment aging, and the environment, and improves the reliability and safety of the equipment.

[0074] Adopting the technical solution of the present invention, by setting up a self-checking circuit for the electrical equipment, through this self-checking circuit, two test points of any power consumption network inside the electrical equipment are detected to determine whether there is a short circuit between the two test points of the power consumption network: if there is a short circuit, the power supply of the power consumption network is disconnected; if there is no short circuit, the power supply of the power consumption network is turned on. Thus, by enabling the electrical equipment to perform self-checking when the electrical equipment is powered on, and only allowing the electrical equipment to be powered on and operate when the self-checking passes, it can at least improve the safety of the electrical equipment itself.

[0075] According to an embodiment of the present invention, there is also provided an electrical equipment corresponding to the power-on self-checking device of the electrical equipment. The electrical equipment may include: the power-on self-checking device of the electrical equipment described above.

[0076] Since the processing and functions implemented by the electrical equipment in this embodiment are basically corresponding to the embodiments, principles, and examples of the device, for the parts not described in detail in the description of this embodiment, reference can be made to the relevant descriptions in the foregoing embodiments, and details will not be repeated here.

[0077] Adopting the technical solution of the present invention, by setting up a self-checking circuit for the electrical equipment, through this self-checking circuit, two test points of any power consumption network inside the electrical equipment are detected to determine whether there is a short circuit between the two test points of the power consumption network: if there is a short circuit, the power supply of the power consumption network is disconnected; if there is no short circuit, the power supply of the power consumption network is turned on, ensuring the safety of the equipment and the operator.

[0078] In summary, it is easy for those skilled in the art to understand that, on the premise of no conflict, the above-mentioned advantageous ways can be freely combined and superimposed.

[0079] The above are only the embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the scope of the claims of the present invention.

Claims

1. An electrical device power-on self-checking device, characterized in that The electrical device has N power consumption networks, where N is a positive integer; the currently measured power consumption network among the N power consumption networks is denoted as the current power consumption network; The power-on self-checking device of the electrical device includes: a power supply unit, an isolation unit, and a switch unit; where, The power supply unit is configured to supply power to the isolation unit and the switch unit when the electrical device is powered on; The isolation unit is configured to use a power supply signal provided by the power supply unit as a first measured signal, and use the signal at any test point in the current power consumption network as a second measured signal to test whether a short circuit fault occurs between the first measured signal and the second measured signal: if no short circuit fault occurs between the first measured signal and the second measured signal, output a first isolation signal; if a short circuit fault occurs between the first measured signal and the second measured signal, output a second isolation signal; the first measured signal is the signal at a point in the current power consumption network that needs to be detected, and this point is connected to the negative pole of the DC / DC power supply as the reference ground of the power supply; the isolation unit includes: a voltage conversion module and an optocoupler module; where, the voltage conversion module is arranged at the output end of the power supply unit and outputs two power supply signals; the two power supply signals include: a positive power supply signal and a negative power supply signal; the positive power supply signal is input to the anode of the diode side in the optocoupler module; the second measured signal is input to the cathode of the diode side in the optocoupler module; the negative power supply signal is used as the first measured signal; the power supply unit is also connected to the collector of the transistor side in the optocoupler module; the emitter of the transistor side in the optocoupler module is connected to the switch unit; The switch unit is configured to control the device main power supply of the electrical device to supply power to the electrical device when receiving the first isolation signal; and control the device main power supply of the electrical device not to supply power to the electrical device when receiving the second isolation signal.

2. The power-on self-checking device of the electrical equipment according to claim 1, characterized in that The power supply unit includes: a separately provided first weak power supply, or a second weak power supply obtained by converting the device main power supply of the electrical device.

3. The power-on self-checking device for the electrical equipment according to claim 1, wherein The isolation unit further includes: a first current limiting module and a second current limiting module; where, The first current limiting module is arranged between the positive power supply signal and the anode of the diode side in the optocoupler module; The second current limiting module is arranged between the power supply unit and the collector of the transistor side in the optocoupler module.

4. The power-on self-checking device of the electrical equipment according to claim 1, characterized in that, The switch unit includes: a first switch tube module and a second switch tube module; where, The emitter of the transistor side in the optocoupler module is connected to the control end of the first switch tube module; the power supply unit is also connected to the first connection end of the first switch tube module; the second connection end of the first switch tube module is connected to the control end of the second switch tube module; The first connection end of the second switch tube module is connected to the electrical device; the second connection end of the second switch tube module is connected to the device main power supply of the electrical device.

5. The power-on self-checking device of the electrical equipment according to claim 4, characterized in that, The first switching transistor module includes: a triode, which is a PNP-type triode; the second switching transistor module includes: a relay; The control terminal of the first switching transistor module is the base of the triode; the first connection terminal of the first switching transistor module is the emitter of the triode; the second connection terminal of the first switching transistor module is the collector of the triode; The control terminal of the second switching transistor module is the coil terminal of the relay; the first connection terminal of the second switching transistor module is the first connection terminal of the normally open contact of the relay; the second connection terminal of the second switching transistor module is the second connection terminal of the normally open contact of the relay.

6. The power-on self-checking device for an electrical equipment according to claim 4, wherein, The switching unit further includes: a delay module; The delay module is disposed between the power supply unit and the first connection terminal of the first switching transistor module.

7. The power-on self-checking device for an electrical appliance according to claim 1, characterized in that It further includes: An alarm module; The alarm module is disposed at the emitter on the transistor side of the optocoupler module.

8. The power-on self-checking device of the electrical equipment according to claim 7, characterized in that It further includes: A third current limiting module; The third current limiting module is disposed between the emitter on the transistor side of the optocoupler module and the alarm module.

9. An electrical device, characterized in that, It includes: The power-on self-checking device of the electrical equipment according to any one of claims 1 to 8.

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