Protection circuit and method for preventing strong voltage damage and electrostatic management tester

Abstract

The invention discloses a protection circuit and method for preventing strong voltage damage and an electrostatic management tester, and belongs to the technical field of power supply protection circuits, the protection circuit comprises a solid-state relay, a voltage acquisition circuit and a resistance acquisition circuit, the solid-state relay is connected to the acquisition end of the voltage acquisition circuit in a normally closed mode, and the resistance acquisition circuit is connected to the resistance acquisition circuit. The solid-state relay is normally open and connected to the acquisition end of the resistance acquisition circuit; the voltage acquisition circuit comprises a direct-current voltage measurement circuit and an alternating-current voltage measurement circuit, when the measured direct-current voltage is smaller than the direct-current threshold voltage or the measured alternating-current voltage is smaller than the alternating-current threshold voltage, a switching signal is sent to the solid-state relay, and the solid-state relay is switched and closed on the acquisition end of the resistance acquisition circuit to measure a resistance value; quickly switching back to the acquisition end of the voltage acquisition circuit; when the measured direct-current voltage is larger than or equal to the direct-current threshold voltage or the measured alternating-current voltage is larger than or equal to the alternating-current threshold voltage, an alarm signal is sent out, and the solid-state relay is connected to the collecting end of the voltage collecting circuit in a normally-closed mode.

Description

Technical Field

[0001] The present invention relates to the technical field of power supply protection circuits, and in particular to a protection circuit and method for preventing damage by strong voltage, and an electrostatic management tester. Background Art

[0002] In industrial production, static electricity can cause serious harm. For example, static electricity can cause dust to be adsorbed on equipment, affecting the filtration and transportation of powders. For example, static electricity discharge can cause electromagnetic interference, which can cause failures and malfunctions of electronic equipment. The current formed during the rapid discharge of static electricity can break through circuits and precision electronic components, causing aging and damage to components. For example, although the energy of static electricity is not large, due to its high voltage and easy discharge, static electricity sparks occur, which can easily cause fires in chemical production. For this reason, some companies in existing industrial production will install static electricity testers to measure and eliminate the static electricity carried by workpieces to improve product production safety.

[0003] When factories manage static electricity, they will regularly use static electricity management testers to check the performance of items, including the ground resistance value of the test equipment, the resistance value of the static electricity ground wire, the resistance value of the power ground wire, etc. When using the resistance range of the static electricity management tester to test resistance, workers sometimes accidentally plug in 220V AC high voltage, causing damage to expensive precision instruments, interrupting work and causing trouble, and also causing unnecessary maintenance costs and maintenance time.

[0004] Therefore, how to provide a protection circuit that can prevent the electrostatic tester from being damaged by a strong voltage is a technical problem that needs to be solved urgently by those skilled in the art. Summary of the invention

[0005] To this end, the present invention provides a protection circuit, method and electrostatic management tester for preventing damage by strong voltage, so as to solve the problem in the prior art that the high voltage caused by incorrect power circuit plugging causes damage to the tester.

[0006] In order to achieve the above object, the present invention provides the following technical solutions: According to a first aspect of the present invention, there is provided a protection circuit for preventing damage by strong voltage, comprising a solid-state relay, a voltage collection circuit and a resistance collection circuit, wherein the solid-state relay is normally closed and connected to the collection end of the voltage collection circuit, and the solid-state relay is normally open and connected to the collection end of the resistance collection circuit; The voltage acquisition circuit includes a DC voltage measurement circuit and an AC voltage measurement circuit, wherein when the measured DC voltage in the DC voltage measurement circuit is less than the DC threshold voltage or the measured AC voltage in the AC voltage measurement circuit is less than the AC threshold voltage, a switching signal is sent to the solid-state relay, and the solid-state relay switches and closes on the acquisition end of the resistance acquisition circuit, measures the resistance value in the resistance acquisition circuit, and quickly switches back to the acquisition end of the voltage acquisition circuit; When the measured DC voltage in the DC voltage measurement circuit is greater than or equal to the DC threshold voltage or the measured AC voltage in the AC voltage measurement circuit is greater than or equal to the AC threshold voltage, an alarm signal is sent to the solid-state relay, and the solid-state relay is normally closed and connected to the collection end of the voltage collection circuit.

[0007] Furthermore, an operational comparison circuit is provided between the solid-state relay and the voltage collection circuit, wherein when the solid-state relay is normally closed and connected to the collection end of the voltage collection circuit, the detection current flows into the voltage collection circuit through the operational comparison circuit.

[0008] Furthermore, a TVS dual protection circuit is provided between the solid-state relay and the resistance collection circuit, wherein when the solid-state relay is switched closed on the collection end of the resistance collection circuit, the detection current flows into the resistance collection circuit through the TVS dual protection circuit.

[0009] Furthermore, the operational comparison circuit includes a comparator U1, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R7, a resistor R8 and a capacitor C1, the positive input end of the comparator U1 is respectively connected to one end of the resistor R1 and the resistor R2, the other end of the resistor R1 is connected to the normally closed end of the solid-state relay Q1, the other end of the resistor R2 is grounded, the negative input end of the comparator U1 is respectively connected to one end of the resistor R3 and the resistor R4, the other end of the resistor R4 is connected to the output end of the comparator U1, the other end of the resistor R3 is grounded, the resistor R5 and the resistor R6 are connected in series to the output end of the comparator U1 and connected to the collection end of the DC voltage measurement circuit, the resistor R7, the resistor R8 and the capacitor C1 are connected in series to the output end of the comparator U1 and connected to the collection end of the AC voltage measurement circuit.

[0010] Furthermore, the TVS dual protection circuit includes a comparator U2, a TVS diode T1, a resistor R9, a resistor R10, a resistor R11, a resistor R12 and a resistor R13, one end of the resistor R9 is connected to the normally open end of the solid-state relay Q1, the other end of the resistor R9 is respectively connected to one end of the TVS diode T1, the resistor R10 and the resistor R11, the other end of the resistor R10 inputs a second reference voltage V2, the other end of the resistor R11 is connected to the positive input end of the comparator U2, one end of the resistor R12 is connected to the negative input end of the comparator U2, the other ends of the TVS diode T1 and the resistor R12 are grounded, the negative input end of the comparator U2 is connected to one end of the resistor R13, the other end of the resistor R13 is connected to the output end of the comparator U2, and is connected to the collection end of the resistance collection circuit.

[0011] Furthermore, the positive electrode of the solid-state relay Q1 is connected to one end of the resistor R14, the other end of the resistor R14 inputs the first reference voltage V1, and the negative electrode of the solid-state relay Q1 is grounded.

[0012] According to a second aspect of the present invention, there is provided a protection method against strong voltage damage, comprising: Determine whether the power supply in the power supply circuit is a DC power supply or an AC power supply; Based on the power supply in the power supply circuit being a DC power supply, obtaining a measured DC voltage in the DC voltage measurement circuit; If the measured DC voltage in the DC voltage measurement circuit is less than the DC threshold voltage, sending a switching signal to the solid-state relay; If the measured DC voltage in the DC voltage measurement circuit is greater than or equal to the DC threshold voltage, sending an alarm signal to the solid-state relay; Based on the power supply in the power supply circuit being an AC power supply, obtaining a measured AC voltage in the AC voltage measurement circuit; If the measured AC voltage in the AC voltage measurement circuit is less than the AC threshold voltage, a switching signal is sent to the solid-state relay; If the measured AC voltage in the AC voltage measurement circuit is greater than or equal to the AC threshold voltage, sending an alarm signal to the solid-state relay; Based on the solid-state relay receiving the switching signal, the solid-state relay switches to close on the collection end of the resistance collection circuit, measures the resistance value in the resistance collection circuit, and quickly switches back to the collection end of the voltage collection circuit; Based on the solid-state relay receiving the alarm signal, the solid-state relay is normally closed and connected to the collection end of the voltage collection circuit.

[0013] Furthermore, based on the solid-state relay switching and closing on the collection end of the resistance collection circuit, if the pulse voltage in the resistance collection circuit is less than the pulse threshold voltage, the output end of the comparator U1 outputs a low level, and the TVS diode T1 is turned on; if the pulse voltage in the resistance collection circuit is greater than or equal to the pulse threshold voltage, the output end of the comparator U1 outputs a high level, and the TVS diode T1 is not turned on.

[0014] According to a third aspect of the present invention, there is provided an electrostatic management tester, wherein a red test lead of the electrostatic management tester is connected to the solid-state relay, and a black test lead of the electrostatic management tester is grounded.

[0015] The present invention has the following advantages: The protection circuit provided in the present application includes a solid-state relay, a voltage acquisition circuit and a resistance acquisition circuit. The solid-state relay is normally closed and connected to the acquisition end of the voltage acquisition circuit, and the solid-state relay is normally open and connected to the acquisition end of the resistance acquisition circuit; the voltage acquisition circuit includes a DC voltage measurement circuit and an AC voltage measurement circuit, wherein, when the measured DC voltage in the DC voltage measurement circuit is less than the DC threshold voltage or the measured AC voltage in the AC voltage measurement circuit is less than the AC threshold voltage, a switching signal is sent to the solid-state relay, the solid-state relay switches and closes on the acquisition end of the resistance acquisition circuit, measures the resistance value in the resistance acquisition circuit, and quickly switches back to the acquisition end of the voltage acquisition circuit; wherein, when the measured DC voltage in the DC voltage measurement circuit is greater than or equal to the DC threshold voltage or the measured AC voltage in the AC voltage measurement circuit is greater than or equal to the AC threshold voltage, the voltage acquisition end sends an alarm signal, and the solid-state relay is normally closed and connected to the acquisition end of the voltage acquisition circuit.

[0016] When the electrostatic management tester provided by the present application tests the electrostatic resistance, it first detects the power supply voltage in the power supply circuit. If the power supply voltage in the power supply circuit is greater than or equal to the preset threshold, an alarm signal is issued to remind the staff that the power supply connected to the power supply circuit is too large. If the power supply voltage in the power supply circuit is less than the preset threshold, it switches to the resistance acquisition circuit, and the red and black test leads of the electrostatic management tester are added to the two ends of the test equipment to measure the electrostatic resistance of the test equipment. The present application avoids the power supply voltage directly acting on the two ends of the electrostatic management tester during resistance measurement, protecting the electrostatic tester from damage by strong voltage. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0018] The structures, proportions, sizes, etc. illustrated in this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with the technology. They are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantial technical significance. Any structural modification, change in proportion or adjustment of size shall still fall within the scope of the technical contents disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0019] Figure 1 A schematic diagram of the structure of a protection circuit for preventing damage from high voltage provided in Example 1 of the present invention. DETAILED DESCRIPTION

[0020] The following is a description of the implementation of the present invention by specific embodiments. People familiar with the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Example

[0021] According to a first aspect of the present invention, there is provided a protection circuit for preventing damage by strong voltage, such as Figure 1 As shown, it includes a solid-state relay, a voltage collection circuit and a resistance collection circuit, the solid-state relay is normally closed and connected to the collection end of the voltage collection circuit, and the solid-state relay is normally open and connected to the collection end of the resistance collection circuit; The voltage acquisition circuit includes a DC voltage measurement circuit and an AC voltage measurement circuit, wherein when the measured DC voltage in the DC voltage measurement circuit is less than the DC threshold voltage or the measured AC voltage in the AC voltage measurement circuit is less than the AC threshold voltage, a switching signal is sent to the solid-state relay, the solid-state relay switches closed on the acquisition end of the resistance acquisition circuit, measures the resistance value in the resistance acquisition circuit, and quickly switches back to the acquisition end of the voltage acquisition circuit; Among them, when the measured DC voltage in the DC voltage measurement circuit is greater than or equal to the DC threshold voltage or the measured AC voltage in the AC voltage measurement circuit is greater than or equal to the AC threshold voltage, an alarm signal is sent to the solid-state relay, and the solid-state relay is normally closed and connected to the collection end of the voltage collection circuit.

[0022] When the electrostatic management tester provided by the present application tests the electrostatic resistance, it first detects the power supply voltage in the power supply circuit. If the power supply voltage in the power supply circuit is greater than or equal to the preset threshold, an alarm signal is issued to remind the staff that the power supply connected to the power supply circuit is too large. If the power supply voltage in the power supply circuit is less than the preset threshold, it switches to the resistance acquisition circuit, and the red and black test leads of the electrostatic management tester are added to the two ends of the test equipment to measure the electrostatic resistance of the test equipment. The present application avoids the power supply voltage directly acting on the two ends of the electrostatic management tester during resistance measurement, protecting the electrostatic tester from damage by strong voltage.

[0023] An operation comparison circuit is also provided between the solid-state relay and the voltage collection circuit, wherein when the solid-state relay is normally closed and connected to the collection end of the voltage collection circuit, the detection current flows into the voltage collection circuit through the operation comparison circuit.

[0024] The operation comparison circuit includes a comparator U1, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R7, a resistor R8 and a capacitor C1. The positive input terminal of the comparator U1 is connected to one end of the resistor R1 and the resistor R2 respectively, the other end of the resistor R1 is connected to the normally closed end of the solid-state relay Q1, the other end of the resistor R2 is grounded, the negative input terminal of the comparator U1 is connected to one end of the resistor R3 and the resistor R4 respectively, the other end of the resistor R4 is connected to the output terminal of the comparator U1, the other end of the resistor R3 is grounded, the resistor R5 and the resistor R6 are connected in series to the output terminal of the comparator U1 and connected to the collection terminal of the DC voltage measurement circuit, the resistor R7, the resistor R8 and the capacitor C1 are connected in series to the output terminal of the comparator U1 and connected to the collection terminal of the AC voltage measurement circuit. The positive electrode of the solid-state relay Q1 is connected to one end of the resistor R14, the other end of the resistor R14 inputs the first reference voltage V1, and the negative electrode of the solid-state relay Q1 is grounded.

[0025] The first reference voltage V1 at the positive input terminal of the comparator U1 is adjusted by adjusting the resistance values ​​of the resistors R1 , R2 and R14 .

[0026] When the power supply in the power supply circuit is a DC power supply, the first reference voltage V1 at the positive input terminal of the comparator U1 is a DC threshold voltage, and the negative input terminal of the comparator U1 measures the measured DC voltage in the DC voltage measurement circuit. By comparing the magnitude relationship between the measured DC voltage and the DC threshold voltage, it is determined what signal is sent to the solid-state relay. If the measured DC voltage in the DC voltage measurement circuit is less than the DC threshold voltage, the output terminal of the comparator U1 outputs a low level, and a switching signal is sent to the solid-state relay; if the measured DC voltage in the DC voltage measurement circuit is greater than or equal to the DC threshold voltage, the output terminal of the comparator U1 outputs a high level, and an alarm signal is sent to the solid-state relay.

[0027] When the power supply in the power supply circuit is an AC power supply, the first reference voltage V1 at the positive input terminal of the comparator U1 is the AC threshold voltage, and the negative input terminal of the comparator U1 measures the measured AC voltage in the AC voltage measurement circuit. By comparing the magnitude relationship between the measured AC voltage and the AC threshold voltage, it is determined what signal is sent to the solid-state relay. If the measured AC voltage in the AC voltage measurement circuit is less than the AC threshold voltage, the output terminal of the comparator U1 outputs a low level, and a switching signal is sent to the solid-state relay; if the measured AC voltage in the AC voltage measurement circuit is greater than or equal to the AC threshold voltage, the output terminal of the comparator U1 outputs a high level, and an alarm signal is sent to the solid-state relay.

[0028] A TVS dual protection circuit is also provided between the solid-state relay and the resistance acquisition circuit. When the solid-state relay is switched closed on the acquisition end of the resistance acquisition circuit, the detection current flows into the resistance acquisition circuit through the TVS dual protection circuit to avoid instantaneous pulses of the line during the resistance measurement process.

[0029] The TVS double protection circuit includes a comparator U2, a TVS diode T1, a resistor R9, a resistor R10, a resistor R11, a resistor R12 and a resistor R13. One end of the resistor R9 is connected to the normally open end of the solid-state relay Q1, and the other end of the resistor R9 is respectively connected to one end of the TVS diode T1, the resistor R10 and the resistor R11. The other end of the resistor R10 inputs a second reference voltage V2, the other end of the resistor R11 is connected to the positive input end of the comparator U2, one end of the resistor R12 is connected to the negative input end of the comparator U2, the other ends of the TVS diode T1 and the resistor R12 are grounded, the negative input end of the comparator U2 is connected to one end of the resistor R13, the other end of the resistor R13 is connected to the output end of the comparator U2, and is connected to the collection end of the resistance collection circuit.

[0030] The negative input terminal of the comparator U2 measures the pulse voltage in the resistance collection circuit, and the positive input terminal of the comparator U2 receives the second reference voltage as the pulse threshold voltage. If the pulse voltage is less than the pulse threshold voltage, the output terminal of the comparator U1 outputs a low level, the TVS diode T1 is turned on, and the solid-state relay is connected to the resistance collection circuit; if the pulse voltage is greater than or equal to the pulse threshold voltage, the output terminal of the comparator U1 outputs a high level, the TVS diode T1 is not turned on, and the solid-state relay is not connected to the resistance collection circuit. Example

[0031] According to a second aspect of the present invention, there is provided a protection method against strong voltage damage, comprising: Determine whether the power supply in the power supply circuit is a DC power supply or an AC power supply; Based on the power supply in the power supply circuit being a DC power supply, obtaining a measured DC voltage in the DC voltage measurement circuit; If the measured DC voltage in the DC voltage measurement circuit is less than the DC threshold voltage, a switching signal is sent to the solid-state relay; If the measured DC voltage in the DC voltage measurement circuit is greater than or equal to the DC threshold voltage, an alarm signal is sent to the solid-state relay; Based on the power supply in the power supply circuit being an AC power supply, obtaining a measured AC voltage in the AC voltage measurement circuit; If the measured AC voltage in the AC voltage measurement circuit is less than the AC threshold voltage, a switching signal is sent to the solid-state relay; If the measured AC voltage in the AC voltage measurement circuit is greater than or equal to the AC threshold voltage, an alarm signal is sent to the solid-state relay; Based on the solid-state relay receiving the switching signal, the solid-state relay switches to close on the collection end of the resistance collection circuit, measures the resistance value in the resistance collection circuit, and quickly switches back to the collection end of the voltage collection circuit; Based on the solid-state relay receiving the alarm signal, the solid-state relay is normally closed and connected to the collection end of the voltage collection circuit.

[0032] Based on the solid-state relay switching and closing on the collection end of the resistance collection circuit, if the pulse voltage is less than the pulse threshold voltage, the output end of the comparator U1 outputs a low level, the TVS diode T1 is turned on, and the solid-state relay is connected to the resistance collection circuit; if the pulse voltage is greater than or equal to the pulse threshold voltage, the output end of the comparator U1 outputs a high level, the TVS diode T1 is not turned on, and the solid-state relay is not connected to the resistance collection circuit.

[0033] Based on the comparison results of the power supply voltage and the threshold voltage in the operation comparison circuit, the contacts of the solid-state relay are controlled to be closed to eliminate the damage to the electrostatic tester caused by high voltage. Based on the comparison results of the pulse voltage and the pulse threshold voltage in the TVS dual protection circuit, the on-off between the solid-state relay and the resistance acquisition circuit is controlled to avoid the interference of the instantaneous pulse of the resistance measurement on the resistance measurement and improve the accuracy of the resistance measurement. Example

[0034] According to the third aspect of the present invention, a static electricity management tester is provided, wherein the red test lead of the static electricity management tester is connected to a solid-state relay, and the black test lead of the static electricity management tester is grounded. When in use, the red and black test leads are connected to both ends of the test equipment, and when the protection circuit in the static electricity management tester outputs a switching signal, the solid-state relay switches to the resistance acquisition circuit, and the static electricity management tester displays the measured resistance of the measuring equipment; when the protection circuit in the static electricity management tester outputs an alarm signal, the solid-state relay is normally closed and connected to the voltage measurement circuit, and the static electricity management tester has no display, and the staff can check whether there is an error in the power supply connection.

[0035] Although the present invention has been described in detail above by general description and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements can be made to the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all belong to the scope of protection claimed by the present invention.

Claims

1. A protection circuit against damage caused by high voltage, characterized in that: It includes a solid-state relay, a voltage collection circuit and a resistance collection circuit, wherein the solid-state relay is normally closed and connected to the collection end of the voltage collection circuit, and the solid-state relay is normally open and connected to the collection end of the resistance collection circuit; The voltage acquisition circuit includes a DC voltage measurement circuit and an AC voltage measurement circuit, wherein when the measured DC voltage in the DC voltage measurement circuit is less than the DC threshold voltage or the measured AC voltage in the AC voltage measurement circuit is less than the AC threshold voltage, a switching signal is sent to the solid-state relay, and the solid-state relay switches and closes on the acquisition end of the resistance acquisition circuit, measures the resistance value in the resistance acquisition circuit, and quickly switches back to the acquisition end of the voltage acquisition circuit; When the measured DC voltage in the DC voltage measurement circuit is greater than or equal to the DC threshold voltage or the measured AC voltage in the AC voltage measurement circuit is greater than or equal to the AC threshold voltage, an alarm signal is sent to the solid-state relay, and the solid-state relay is normally closed and connected to the collection end of the voltage collection circuit.

2. The protection circuit against high voltage damage as claimed in claim 1, characterized in that: An operation comparison circuit is also provided between the solid-state relay and the voltage collection circuit, wherein when the solid-state relay is normally closed and connected to the collection end of the voltage collection circuit, the detection current flows into the voltage collection circuit through the operation comparison circuit.

3. The protection circuit against high voltage damage as claimed in claim 1, characterized in that: A TVS dual protection circuit is also provided between the solid-state relay and the resistance collection circuit, wherein when the solid-state relay is switched closed on the collection end of the resistance collection circuit, the detection current flows into the resistance collection circuit through the TVS dual protection circuit.

4. The protection circuit against high voltage damage as claimed in claim 2, characterized in that: The operational comparison circuit includes a comparator U1, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R7, a resistor R8 and a capacitor C1. The positive input end of the comparator U1 is connected to one end of the resistor R1 and the resistor R2 respectively, the other end of the resistor R1 is connected to the normally closed end of the solid-state relay Q1, the other end of the resistor R2 is grounded, the negative input end of the comparator U1 is connected to one end of the resistor R3 and the resistor R4 respectively, the other end of the resistor R4 is connected to the output end of the comparator U1, the other end of the resistor R3 is grounded, the resistor R5 and the resistor R6 are connected in series to the output end of the comparator U1 and connected to the collection end of the DC voltage measurement circuit, the resistor R7, the resistor R8 and the capacitor C1 are connected in series to the output end of the comparator U1 and connected to the collection end of the AC voltage measurement circuit.

5. The protection circuit against strong voltage damage as claimed in claim 3, characterized in that: The TVS dual protection circuit includes a comparator U2, a TVS diode T1, a resistor R9, a resistor R10, a resistor R11, a resistor R12 and a resistor R13, one end of the resistor R9 is connected to the normally open end of the solid-state relay Q1, the other end of the resistor R9 is respectively connected to one end of the TVS diode T1, the resistor R10 and the resistor R11, the other end of the resistor R10 inputs a second reference voltage V2, the other end of the resistor R11 is connected to the positive input end of the comparator U2, one end of the resistor R12 is connected to the negative input end of the comparator U2, the other ends of the TVS diode T1 and the resistor R12 are grounded, the negative input end of the comparator U2 is connected to one end of the resistor R13, the other end of the resistor R13 is connected to the output end of the comparator U2, and is connected to the collection end of the resistance collection circuit.

6. The protection circuit against high voltage damage as claimed in claim 1, characterized in that: The positive electrode of the solid-state relay Q1 is connected to one end of the resistor R14, the other end of the resistor R14 inputs the first reference voltage V1, and the negative electrode of the solid-state relay Q1 is grounded.

7. A protection method against strong voltage damage, applied to the protection circuit against strong voltage damage as claimed in any one of claims 1 to 6, characterized in that: include: Determine whether the power supply in the power supply circuit is a DC power supply or an AC power supply; Based on the power supply in the power supply circuit being a DC power supply, obtaining a measured DC voltage in the DC voltage measurement circuit; If the measured DC voltage in the DC voltage measurement circuit is less than the DC threshold voltage, sending a switching signal to the solid-state relay; If the measured DC voltage in the DC voltage measurement circuit is greater than or equal to the DC threshold voltage, sending an alarm signal to the solid-state relay; Based on the power supply in the power supply circuit being an AC power supply, obtaining a measured AC voltage in the AC voltage measurement circuit; If the measured AC voltage in the AC voltage measurement circuit is less than the AC threshold voltage, a switching signal is sent to the solid-state relay; If the measured AC voltage in the AC voltage measurement circuit is greater than or equal to the AC threshold voltage, sending an alarm signal to the solid-state relay; Based on the solid-state relay receiving the switching signal, the solid-state relay switches to close on the collection end of the resistance collection circuit, measures the resistance value in the resistance collection circuit, and quickly switches back to the collection end of the voltage collection circuit; Based on the solid-state relay receiving the alarm signal, the solid-state relay is normally closed and connected to the collection end of the voltage collection circuit.

8. The protection method against high voltage damage according to claim 7, characterized in that: Based on the solid-state relay switching and closing on the collection end of the resistance collection circuit, if the pulse voltage in the resistance collection circuit is less than the pulse threshold voltage, the output end of the comparator U1 outputs a low level, and the TVS diode T1 is turned on; if the pulse voltage in the resistance collection circuit is greater than or equal to the pulse threshold voltage, the output end of the comparator U1 outputs a high level, and the TVS diode T1 is not turned on.

9. An electrostatic management tester, comprising a protection circuit for preventing damage from high voltage as claimed in any one of claims 1 to 6, characterized in that: The red test lead of the electrostatic management tester is connected to the solid-state relay, and the black test lead of the electrostatic management tester is grounded.

Images