Electric leakage protection electromagnetic tripping mechanism

Abstract

The utility model belongs to the field of circuit breakers, and particularly relates to a leakage protection electromagnetic tripping mechanism, which comprises an electromagnetic tripper, a buffer piece, a reset piece, an energy storage spring and a transmission piece, when an operating mechanism rotates to a closing position, the reset piece is in limiting fit with the buffer piece, the reset piece is kept at a locking position, and the energy storage spring stores energy; when the electromagnetic tripper receives a line fault signal, the ejection force of the ejector rod of the electromagnetic tripper enables the buffer piece and the reset piece to release the limiting fit, the reset piece slides from the locking position to the unlocking position, and the energy storage spring releases energy to enable the reset piece to impact the lock catch of the operating mechanism to execute the tripping action. The buffer piece adopts an elastic buffer structure design, the buffer piece can reduce the impact force on the ejector rod of the electromagnetic tripper, the service life of the electromagnetic tripper can be prolonged, the reset piece adopts an energy storage structure design, the energy storage spring can assist the reset piece to impact the lock catch of the operating mechanism to execute the tripping action, and the tripping action is more sensitive.

Description

Technical Field

[0001] This utility model belongs to the field of circuit breaker technology, specifically relating to a leakage current protection electromagnetic tripping mechanism. Background Technology

[0002] A miniature residual current circuit breaker (RCCB) is an electrical protection device that integrates overload, short-circuit, and residual current protection functions. It is mainly used to detect leakage or electric shock current in the power grid and triggers a tripping action when a specific current value is detected, thereby cutting off the power supply to protect equipment and personal safety. The electromagnetic trip unit is an important component of the circuit breaker. When a line fault occurs, the electromagnetic trip unit causes the circuit breaker to trip and disconnect the circuit, thus protecting the line. After the fault is cleared, the circuit breaker needs to be reclosed. This requires resetting the electromagnetic trip unit's push rod; otherwise, the circuit breaker will not be able to be closed.

[0003] In existing electromagnetic tripping mechanisms, during reset, the contact mechanism drives the push rod of the electromagnetic trip unit via a reset rod to perform the reset action. This reset rod is a rigid component, and the push rod of the electrical trip unit is subjected to significant impact force during reset. All the reset force of the push rod is applied to the armature of the electromagnetic trip unit. Due to its high magnetic permeability, the armature of the electromagnetic trip unit requires heat treatment. After heat treatment, the surface hardness of the armature is only 95-115 HV, making it relatively soft. Under significant reset forces (greater than 4N), it is prone to deformation, leading to failure of the electromagnetic trip unit and significantly shortening its service life. Furthermore, during tripping, the push rod of the electromagnetic trip unit impacts the locking latch of the operating mechanism via the reset rod to perform the tripping action, causing the operating mechanism to trip and open the circuit breaker. This structural design results in a relatively small tripping force, leading to insensitive tripping action. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings and deficiencies of the existing technology and to provide a leakage protection electromagnetic tripping mechanism that effectively prevents the electromagnetic tripping device from failing due to reset impact force and has sensitive tripping action.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a leakage current protection electromagnetic tripping mechanism, comprising an electromagnetic trip unit fixedly installed inside a housing; a buffer member having an elastic buffer structure, rotatably disposed inside the housing and cooperating with the top rod of the electromagnetic trip unit; a reset member cooperating with the buffer member and sliding relative to the housing, having a locked position and an unlocked position, wherein an energy storage spring is provided between the reset member and the housing; and a transmission member rotatably disposed inside the housing, used to transmit the opening force of the moving contact frame of the operating mechanism to the reset member; when the operating mechanism rotates to the closing position, the... The reset component and the buffer component are in a limiting engagement. The reset component is held in the locked position and the energy storage spring is energized. When the electromagnetic trip unit receives a line fault signal, the pushing force of the top rod of the electromagnetic trip unit causes the buffer component and the reset component to release the limiting engagement. The reset component slides from the locked position to the unlocked position, and the energy storage spring releases energy, causing the reset component to strike the latch of the operating mechanism to perform a tripping action. When the moving contact frame of the operating mechanism rotates in the opening direction, the opening force of the moving contact frame causes the transmission component to push the reset component to strike the elastic buffer structure of the buffer component. The buffer component pushes the top rod of the electromagnetic trip unit to reset.

[0006] In some embodiments, one end of the reset member has a locking part that cooperates with the buffer member, the buffer member has a locking arm that cooperates with the locking part, the locking part is fastened to the locking arm, and the buffer member and the reset member are locked together; the other end of the reset member has a triggering part for triggering the latch to perform a release action.

[0007] In some embodiments, the buffer member has a trigger arm that engages with the push rod of the electromagnetic trip unit, a buffer torsion spring is fitted on the buffer member, the buffer torsion spring has a first buffer arm that abuts against the trigger arm, and the buffer torsion spring has a second buffer arm that engages with the locking part.

[0008] In some embodiments, a reset torsion spring is fitted onto the buffer member, the first torsion arm of the reset torsion spring abuts against the locking arm, the second torsion arm of the reset torsion spring abuts against the limiting arm of the buffer member, and a limiting block that cooperates with the limiting arm is provided inside the housing.

[0009] In some embodiments, the locking arm is provided with a locking groove that cooperates with the locking part, the locking part has a locking protrusion that engages with the locking groove, the locking arm has a fastening guide surface that cooperates with the locking protrusion, and the locking protrusion moves with the locking part and slides along the fastening guide surface into the locking groove.

[0010] In some embodiments, a sliding groove is provided between the housing and the buffer member and the latch, and the housing is provided with a cover plate covering the sliding groove. A guide sliding space is formed between the cover plate and the sliding groove, allowing the reset member to slide back and forth.

[0011] In some embodiments, the reset member is provided with a receiving hole for accommodating the energy storage spring, the sliding groove is provided with a guide block inserted into the receiving hole, the receiving hole has a positioning post near the trigger part, one end of the energy storage spring is engaged with the positioning post, and the other end of the energy storage spring abuts against the guide block.

[0012] In some embodiments, the transmission member has a transmission arm that cooperates with the moving contact frame of the operating mechanism. The moving contact frame of the operating mechanism is provided with a toggle part that cooperates with the transmission arm. When the moving contact frame rotates in the opening direction, the toggle part moves with the moving contact frame and drives the transmission member to rotate.

[0013] In some embodiments, the transmission member has a toggle arm that cooperates with the reset member, and the reset member has a lever portion that cooperates with the toggle arm. The toggle arm moves with the transmission member and drives the lever portion, thus forming a linkage between the lever portion and the transmission member.

[0014] In some embodiments, the transmission component is fitted with a power-taking torsion spring for connecting or disconnecting the power supply of the test device. One end of the power-taking torsion spring has a conductive arm that abuts against the conductive part of the stationary contact, and the other end of the power-taking torsion spring has a power-taking arm that abuts against the driving arm of the transmission component. When the moving contact frame rotates to the open position, the driving arm of the transmission component moves with the moving contact frame and separates the power-taking arm from the test device, thereby disconnecting the power supply of the test device. When the moving contact frame rotates to the closed position, the driving arm of the transmission component moves with the moving contact frame and contacts the power-taking arm with the test device, thereby connecting the power supply of the test device.

[0015] The beneficial effects of this utility model are as follows: The use of a buffer component with an elastic buffer structure to drive the top rod of the electromagnetic trip unit for reset, the damping effect of the buffer component controls the reset force of the reset component to within 4N, thus effectively preventing deformation of the armature of the electromagnetic trip unit due to excessive impact force of the reset component, which helps extend the service life of the electromagnetic trip unit. The reset component adopts an energy storage structure design; the energy storage spring assists the reset component in impacting the latch of the operating mechanism to execute the tripping action, effectively increasing the tripping force of the electromagnetic trip unit mechanism and making the tripping action more sensitive. A power-taking torsion spring is added to the reverse connection circuit of the circuit breaker. When the moving contact frame of the operating mechanism rotates to the open position during reverse connection, the moving contact frame drives the power-taking conversion component to operate. The driving arm of the power-taking conversion component drives the power-taking arm of the power-taking torsion spring to separate from the conductive arm of the test device. The power-taking torsion spring cuts off the power supply to the test device, and the power supply to the test device is in a de-energized state, thus preventing damage to the test circuit. When the circuit breaker is connected in the forward direction, the operating mechanism controls the test device to disconnect the power through the moving contact and the stationary contact, thereby achieving the purpose of forward and reverse wiring of the circuit breaker, making the wiring more convenient. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, obtaining other drawings based on these drawings without creative effort still falls within the scope of this utility model.

[0017] Figure 1 This is a perspective view of the internal structure of the circuit breaker according to an embodiment of the present invention;

[0018] Figure 2 This is a structural diagram of the electromagnetic tripping mechanism for leakage protection in an embodiment of this utility model;

[0019] Figure 3 This is a structural diagram of the circuit breaker in the closed state according to an embodiment of the present invention;

[0020] Figure 4 This is a structural diagram of the circuit breaker in the tripped state according to an embodiment of the present utility model;

[0021] Figure 5 This is a perspective view of the buffer component according to an embodiment of the present utility model;

[0022] Figure 6 This is a perspective view of the reset component according to an embodiment of the present utility model;

[0023] Figure 7 This is a perspective view of the transmission component in an embodiment of the present utility model. Detailed Implementation

[0024] To make the technical problem to be solved, the technical solution, and the beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this utility model and are not intended to limit this utility model.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. The terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0026] The directional and positional terms used in this utility model, such as up, down, front, back, left, right, inside, outside, top, bottom, side, etc., are only for reference to the accompanying drawings. Therefore, the directional and positional terms used are for the purpose of explaining and understanding this utility model, and not for limiting the scope of protection of this utility model.

[0027] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments:

[0028] like Figure 1-4 As shown, a leakage current protection electromagnetic tripping mechanism includes an electromagnetic trip unit 11, fixedly installed inside a housing 10; a buffer member 12, having an elastic buffer structure, rotatably disposed inside the housing 10 and cooperating with the push rod 111 of the electromagnetic trip unit 11; a reset member 13, cooperating with the buffer member 12 and sliding relative to the housing 10, having a locked position and an unlocked position, with an energy storage spring 14 disposed between the reset member 13 and the housing 10; and a transmission member 15, rotatably disposed inside the housing 10, used to transmit the opening force of the moving contact frame 161 of the operating mechanism 16 to the reset member 13; when the operating mechanism 16 rotates to the closing position, the reset member 13 and the buffer member 12 are limited. In coordination, the reset member 13 remains in the locked position and the energy storage spring 14 stores energy. When the electromagnetic trip unit 11 receives a line fault signal, the push force of the push rod 111 of the electromagnetic trip unit 11 causes the buffer member 12 and the reset member 13 to release their limiting coordination. The reset member 13 slides from the locked position to the unlocked position. The energy storage spring 14 releases energy, causing the reset member 13 to strike the latch 162 of the operating mechanism 16 to perform the tripping action. When the moving contact frame 161 of the operating mechanism 16 rotates in the opening direction, the opening force of the moving contact frame 161 causes the transmission member 15 to push the reset member 13 to strike the elastic buffer structure of the buffer member 12. The buffer member 12 pushes the push rod 111 of the electromagnetic trip unit 11 to reset. Traditional electromagnetic trip units use a rigid reset rod to drive the top rod of the electromagnetic trip unit to reset. The reset force of this rod is greater than 7N, while the armature of the electromagnetic trip unit can only withstand a maximum impact force of 4N. After prolonged use, the armature of the electromagnetic trip unit is prone to deformation, significantly shortening its service life (≤2000 cycles). This invention, however, uses a buffer component with an elastic buffer structure to drive the top rod of the electromagnetic trip unit to reset. The damping effect of the buffer component controls the reset force to within 4N, effectively preventing deformation of the armature due to excessive impact force and extending the service life of the electromagnetic trip unit (≤4000 cycles). The reset component adopts an energy storage structure design; the energy storage spring assists the reset component in impacting the locking mechanism of the operating mechanism to execute the tripping action, effectively increasing the tripping force of the electromagnetic trip unit mechanism and making the tripping action more sensitive.

[0029] like Figure 2-6As shown, one end of the reset member 13 has a locking part 131 that cooperates with the buffer member 12. The buffer member 12 has a locking arm 121 that cooperates with the locking part 131. The locking part 131 is fastened to the locking arm 121, thus locking the buffer member 12 and the reset member 13. The other end of the reset member 13 has a trigger part 132 for triggering the latch 162 to perform a tripping action. The reset member is fastened to the locking arm of the buffer member through the locking part, thereby ensuring that the buffer member and the reset member can be reliably locked or unlocked. The reset member strikes the latch of the operating mechanism through the trigger part, thereby realizing the reliable tripping of the circuit breaker. The buffer member 12 has a trigger arm 122 that cooperates with the push rod 111 of the electromagnetic trip device 11. A buffer torsion spring 17 is fitted on the buffer member 12. The buffer torsion spring 17 has a first buffer arm 171 that abuts against the trigger arm 122 and a second buffer arm 172 that cooperates with the locking part 131. The buffer torsion spring buffers the reset force of the reset component. The damping effect of the buffer torsion spring reduces the impact force of the buffer component on the top rod of the electromagnetic trip unit, thus extending the service life of the electromagnetic trip unit. A reset torsion spring 18 is fitted onto the buffer component 12. The first torsion arm 181 of the reset torsion spring 18 abuts against the locking arm 121, and the second torsion arm 182 of the reset torsion spring 18 abuts against the limiting arm 123 of the buffer component 12. A limiting block 101 that cooperates with the limiting arm 123 is provided inside the housing 10. The reset torsion spring ensures reliable reset of the buffer component, and the limiting block of the housing limits the limiting arm, thus ensuring reliable rotation of the buffer component within the housing. The locking arm 121 is provided with a locking groove 1211 that cooperates with the locking part 131. The locking part 131 has a locking protrusion 1311 that engages with the locking groove 1211. The locking arm 121 has a fastening guide surface 1212 that engages with the locking protrusion 1311. The locking protrusion 1311 moves with the locking part 131 and slides along the fastening guide surface 1212 into the locking groove 1211. The locking part is fastened in the locking groove of the locking arm by the locking protrusion, thereby ensuring that the locking arm of the buffer member and the locking part of the reset member can be reliably locked. The fastening guide surface guides the locking protrusion, ensuring that the locking protrusion and the locking groove can be reliably fastened.

[0030] like Figure 1-3As shown, a sliding groove 102 is provided between the buffer member 12 and the latch 162 in the housing 10. The housing 10 is provided with a cover plate 19 covering the sliding groove 102. A guide sliding space is formed between the cover plate 19 and the sliding groove 102, allowing the reset member 13 to slide back and forth. The reset member is slidably disposed in the sliding groove of the housing, thereby ensuring that the reset member can reliably operate within the housing, and the cover plate can play a protective role, ensuring that the reset member can reliably operate within the guide sliding space. The reset member 13 is provided with a receiving hole 133 for accommodating the energy storage spring 14. A guide block 103 is provided in the sliding groove 102 and inserted into the receiving hole 133. A positioning post 134 is provided in the receiving hole 133 near the trigger part 132. One end of the energy storage spring 14 is engaged with the positioning post 134, and the other end of the energy storage spring 14 abuts against the guide block 103. The energy storage spring is engaged between the positioning post of the reset component and the guide block of the housing, which facilitates the assembly of the energy storage spring with the reset component and the housing. This ensures that the energy storage spring can reliably store and release energy, and can reliably assist the reset component in striking the latch of the operating mechanism to perform the release action, thereby improving the release sensitivity of the electromagnetic release mechanism.

[0031] like Figure 2 , 6 As shown in Figure 7, the transmission member 15 has a transmission arm 151 that cooperates with the moving contact frame 161 of the operating mechanism 16. The moving contact frame 161 of the operating mechanism 16 is provided with a toggle part 1611 that cooperates with the transmission arm 151. When the moving contact frame 161 rotates in the opening direction, the toggle part 1611 moves with the moving contact frame 161 and drives the transmission member 15 to rotate. The moving contact frame drives the transmission arm of the transmission member through the toggle part, thereby ensuring that the moving contact frame can reliably drive the transmission member to rotate. The transmission member 15 has a toggle arm 152 that cooperates with the reset member 13. The reset member 13 has a lever part 135 that cooperates with the toggle arm 152. The toggle arm 152 moves with the transmission member 15 and drives the lever part 135, forming a linkage between the lever part 135 and the transmission member 15. The transmission member drives the lever part of the reset member through the toggle arm, thereby ensuring that the transmission member can reliably drive the reset member to slide within the housing.

[0032] like Figure 1 , 2As shown in Figures 4 and 7, a power-taking torsion spring 21 for connecting or disconnecting the power supply of the test device 20 is mounted on the transmission component 15. One end of the power-taking torsion spring 21 has a conductive arm 211 that abuts against the conductive part 221 of the stationary contact 22, and the other end of the power-taking torsion spring 21 has a power-taking arm 212 that abuts against the driving arm 153 of the transmission component 15. When the moving contact frame 161 rotates to the open position, the driving arm 153 of the transmission component 15 moves with the moving contact frame 161 and causes the power-taking arm 212 to separate from the test device 20, thereby disconnecting the power supply of the test device 20. When the moving contact frame 161 rotates to the closed position, the driving arm 153 of the transmission component 15 moves with the moving contact frame 161 and causes the power-taking arm 212 to contact the test device 20, thereby connecting the power supply of the test device 20. The test device 20 includes a test button 201 mounted on the housing 10 and a test torsion spring 202 mounted inside the housing 10. The drive arm 153 of the transmission component 15 drives the power-taking arm 212 of the power-taking torsion spring 21 to contact or separate from the test torsion spring 202, thereby realizing the connection or disconnection of the power supply to the test device 20. By adding a power-taking torsion spring to the reverse circuit of the circuit breaker, when the moving contact of the operating mechanism rotates to the open position during reverse wiring, the moving contact drives the power-taking conversion component to operate. The drive arm of the power-taking conversion component drives the power-taking arm of the power-taking torsion spring to separate from the conductive arm of the test device, and the power-taking torsion spring cuts off the power supply to the test device. The power supply to the test device is in a de-energized state, thus preventing damage to the test circuit. During forward wiring, the operating mechanism controls the power disconnection of the test device through the moving and stationary contacts, thereby achieving the purpose of forward and reverse wiring of the circuit breaker, making wiring more convenient.

[0033] The working principle of the electromagnetic tripping mechanism for leakage current protection is as follows: When the electromagnetic trip unit receives a line fault signal, the push rod of the electromagnetic trip unit drives the buffer to rotate. The locking arm of the buffer disengages from the locking part of the reset component, and the reset component slides from the locked position to the unlocked position. The energy storage spring releases energy, causing the reset component to strike the latch of the operating mechanism to perform the tripping action. During the opening process, the opening force of the moving contact frame drives the transmission component to rotate. The transmission component drives the locking part of the reset component to strike the buffer torsion spring of the buffer component. The buffer torsion spring causes the buffer component to push the push rod of the electromagnetic trip unit to reset. During the closing process, the transmission component loses the opening force applied by the moving contact frame, and the force of the energy storage spring drives the locking part of the reset component to engage with the locking arm of the buffer component, keeping the reset component in the locked position.

[0034] The above description is only one embodiment of the present utility model and is not intended to limit the scope of protection of the present utility model; the scope of protection of the present utility model is defined by the claims in the claims, and all equivalent changes and modifications made in accordance with the utility model are within the scope of protection of the present utility model patent.

Claims

1. An arc fault protection electromagnetic trip unit characterized by: include The electromagnetic trip unit is fixedly installed inside the housing; The buffer component has an elastic buffer structure, is rotatably mounted inside the housing, and cooperates with the top rod of the electromagnetic trip unit. A reset component, which cooperates with a buffer component and slides relative to the housing, has a locked position and an unlocked position, and an energy storage spring is provided between the reset component and the housing. The transmission component is rotatably disposed within the housing and is used to transmit the opening force of the moving contact frame of the operating mechanism to the reset component; When the operating mechanism rotates to the closed position, the reset component and the buffer component engage in a limiting cooperation. The reset component remains in the locked position and the energy storage spring stores energy. When the electromagnetic trip unit receives a line fault signal, the pushing force of the electromagnetic trip unit's push rod causes the buffer component and the reset component to release their limiting cooperation. The reset component slides from the locked position to the unlocked position, and the energy storage spring releases energy, causing the reset component to strike the locking latch of the operating mechanism to perform a tripping action. When the moving contact frame of the operating mechanism rotates in the opening direction, the opening force of the moving contact frame causes the transmission component to push the reset component to strike the elastic buffer structure of the buffer component. The buffer component pushes the push rod of the electromagnetic trip unit to reset.

2. The ground fault protection electromagnetic trip unit of claim 1, wherein: The reset member has a locking part at one end that cooperates with the buffer member, and the buffer member has a locking arm that cooperates with the locking part. The locking part is fastened to the locking arm and forms a lock between the buffer member and the reset member. The other end of the reset member has a triggering part for triggering the latch to perform a release action.

3. The ground fault protection electromagnetic trip unit of claim 2, wherein: The buffer component has a trigger arm that cooperates with the push rod of the electromagnetic trip unit. A buffer torsion spring is fitted on the buffer component. The buffer torsion spring has a first buffer arm that abuts against the trigger arm and a second buffer arm that cooperates with the locking part.

4. The ground fault protection electromagnetic trip unit of claim 2 or 3, wherein: The buffer is fitted with a reset torsion spring. The first torsion arm of the reset torsion spring abuts against the locking arm, and the second torsion arm of the reset torsion spring abuts against the limiting arm of the buffer. A limiting block that cooperates with the limiting arm is provided inside the housing.

5. The ground fault protection electromagnetic trip unit of claim 2 or 3, wherein: The locking arm is provided with a locking groove that cooperates with the locking part. The locking part has a locking protrusion that engages with the locking groove. The locking arm has a fastening guide surface that cooperates with the locking protrusion. The locking protrusion moves with the locking part and slides along the fastening guide surface into the locking groove.

6. The ground fault protection electromagnetic release according to claim 2 or 3, characterized in that: The housing is provided with a sliding groove between the buffer and the latch, and the housing is provided with a cover plate covering the sliding groove. A guide sliding space is formed between the cover plate and the sliding groove, which allows the reset member to slide back and forth.

7. The ground fault protection electromagnetic release of claim 6, wherein: The reset component is provided with a receiving hole for accommodating the energy storage spring. A guide block is provided in the sliding groove and inserted into the receiving hole. A positioning post is provided in the receiving hole near the trigger part. One end of the energy storage spring is engaged with the positioning post, and the other end of the energy storage spring abuts against the guide block.

8. The ground fault protection electromagnetic release of claim 1, wherein: The transmission component has a transmission arm that cooperates with the moving contact frame of the operating mechanism. The moving contact frame of the operating mechanism is provided with a toggle part that cooperates with the transmission arm. When the moving contact frame rotates in the opening direction, the toggle part moves with the moving contact frame and drives the transmission component to rotate.

9. The ground fault protection electromagnetic release of claim 8, wherein: The transmission component has a toggle arm that cooperates with the reset component, and the reset component has a lever portion that cooperates with the toggle arm. The toggle arm moves with the transmission component and drives the lever portion, thus forming a linkage between the lever portion and the transmission component.

10. The ground fault protection electromagnetic release according to claim 8 or 9, characterized in that: The transmission component is fitted with a torsion spring for connecting or disconnecting the power supply of the test device. One end of the torsion spring has a conductive arm that abuts against the conductive part of the stationary contact, and the other end of the torsion spring has a power-taking arm that abuts against the driving arm of the transmission component. When the moving contact frame rotates to the open position, the driving arm of the transmission component moves with the moving contact frame and separates the power-taking arm from the test device, thereby disconnecting the power supply of the test device. When the moving contact frame rotates to the closed position, the driving arm of the transmission component moves with the moving contact frame and contacts the power-taking arm with the test device, thereby connecting the power supply of the test device.

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