阅读说明：本技术 一种带检测接触电阻功能的接地装置 (Grounding device with contact resistance detection function ) 是由 孙家军 王毅 李继武 邱宇晟 李通 徐永波 韩勇 孙乾亮 李治君 夏奔飞 于 2021-03-02 设计创作，主要内容包括：本发明一种带检测接触电阻功能的接地装置属于电力系统设备检修领域,具体的是一种保障电力系统设备检修可靠接地的接地设备,特别适用于高电压设备检修保护接地。一种带检测接触电阻功能的接地装置具有线夹、测量回路,线夹包括主体框、顶压杆和顶压块、引流线,测量回路包括试验按钮、测量回路线、接触片、检测设备；引流线和测量回路线并行于透明绝缘护套内；其中主体框为门型或U形的具有开口的能够导电的框架,引流线与主体框连接,引流线的另一端电连接有测量装置；所述的顶压杆为螺纹杆,在主体框的下方设置有对应的内螺纹通孔,顶压杆的顶端活动连接有顶压块,顶压块位于主体框内,顶压杆的下方连接有绝缘杆。(The invention discloses a grounding device with a contact resistance detection function, belongs to the field of power system equipment maintenance, particularly relates to grounding equipment for ensuring reliable grounding of power system equipment maintenance, and is particularly suitable for high-voltage equipment maintenance and grounding protection. A grounding device with a contact resistance detection function is provided with a wire clamp and a measurement loop, wherein the wire clamp comprises a main body frame, a jacking rod, a jacking block and a drainage wire, and the measurement loop comprises a test button, a measurement loop line, a contact piece and detection equipment; the drainage wire and the measuring loop line are parallel to the inside of the transparent insulating sheath; the drainage wire is connected with the main body frame, and the other end of the drainage wire is electrically connected with a measuring device; the top pressure rod is a threaded rod, a corresponding internal thread through hole is formed in the lower portion of the main body frame, a top pressure block is movably connected to the top end of the top pressure rod and located in the main body frame, and an insulating rod is connected to the lower portion of the top pressure rod.)

1. The utility model provides a grounding device of contact resistance function is detected in area which characterized in that: the device is provided with a wire clamp and a measuring loop, wherein the wire clamp comprises a main body frame, a jacking rod, a jacking block and a drainage wire, and the measuring loop comprises a test button, a measuring loop line, a contact piece and a detecting device; the drainage wire and the measuring loop line are parallel;

the drainage wire is connected with the main body frame, and the other end of the drainage wire is connected with a measuring device; the top pressure rod is a threaded rod, a corresponding internal thread through hole is formed below the main body frame, the top end of the top pressure rod is movably connected with a top pressure block, the top pressure block is located in the main body frame, an insulating rod is connected below the top pressure rod, and the lifting of the top pressure block can be controlled by rotating the insulating rod;

the upper surface of the jacking block is provided with a dovetail groove, and the dovetail groove can be connected with a measurement contact body in a tenon-and-mortise mode;

the measuring contact body is provided with a mounting fixed block, an insulating layer and a contact piece from bottom to top respectively; the bottom of the mounting fixing block is provided with a clamping tenon matched with the dovetail groove, the side face of the contact piece is provided with a wiring hole, the wiring hole is connected with a measuring return line, and the other end of the measuring return line is connected with a measuring device.

2. The grounding device with the function of detecting contact resistance according to claim 1, characterized in that: the drainage wire and the measuring loop line are parallel to each other, the drainage wire and the measuring loop line are wrapped together through the transparent outer sheath, the measuring loop line is provided with an insulating layer, wiring of a cable is gathered and certain insulation is kept, one or three measuring loop lines are provided, single-phase electricity is measured when one measuring loop line is used, and each phase of three-phase electricity is measured when three measuring loop lines are used;

the drainage thread is divided into three head ends and a tail end, the head ends are three, the tail end is one, and the head ends and the tail end are electrically connected.

3. The grounding device with the function of detecting contact resistance according to claim 1, characterized in that: the back of the top pressure block is welded or riveted with a mouth-shaped frame, a through hole is formed in the mouth-shaped frame, a screw head is arranged at the top of the top pressure rod and is located in the mouth-shaped frame, and therefore the top pressure rod can push the top pressure block to move up and down without rotating.

4. The grounding device with the function of detecting contact resistance according to claim 1, characterized in that: the rear side of the main body frame is provided with a back fin, the back fin is provided with a connecting hole, the drainage wire is electrically connected with the main body frame through the connecting hole, and the connecting hole is a threaded hole.

5. The grounding device with the function of detecting contact resistance according to claim 1, characterized in that: the measuring device is provided with a cuboid shell, an equipment bin is arranged in the shell, a battery and detection equipment are respectively installed in the equipment bin from bottom to top, a cover plate is arranged above the equipment bin and fixedly connected with the shell through screws, a through observation window is arranged on the cover plate and positioned above the detection equipment, 2 or 4 test buttons are arranged on one side of the cover plate positioned above the observation window, wherein the single-phase electricity is tested when 2 test buttons are arranged, and the three-phase electricity is tested when 4 test buttons are arranged; one of the 2 or 4 test buttons is a power switch button, the rest are test buttons, and each test button is respectively connected with the corresponding measuring circuit line; the two ends of the shell are respectively provided with a connecting wire nose, the connecting wire nose at one side of the shell is connected with a drainage wire through an adapter, and the adapter is connected with the detection equipment; the connecting wire nose electricity of the opposite side of casing is connected with the earth bar, and the earth bar ground connection plays the voltage effect of letting out and guarantees that the maintenance equipment does not take the voltage.

6. The grounding device with the function of detecting contact resistance of claim 5, wherein: the detection device is an ohmmeter with a liquid crystal display screen, the detection device is electrically connected with the shell, and the ohmmeter is a commercially available proportional measurement ohmmeter.

7. The grounding device with the function of detecting contact resistance of claim 5, wherein: the battery is a lithium battery or a silver-zinc battery.

8. The grounding device with the function of detecting contact resistance according to claim 1, characterized in that: the drainage wire is a main passage for drainage and pressure relief, and the cross section of the drainage wire is 25mm ²Or 35mm²The flexible copper wires are connected, the outer side of the flexible copper wires is sleeved with a transparent insulating sheath, three of the head ends of the flexible copper wires are respectively connected to three (A, B, C) wire clamps, the other ends of the flexible copper wires are connected together to form a connection point which is used as a three-phase short circuit wire, and one of the three short circuit wires is led out from the short circuit point and connected to a shell of the measuring device and then connected to the ground through a ground rod.

9. The grounding device with contact resistance detection function according to claim 8, characterized in that: the cross section of the measuring loop line is smaller than that of the soft copper core insulated wire of the drainage wire.

10. A working method of a grounding device with a contact resistance detection function is characterized in that: when the device is used, the opening of the U-shaped main body frame is clamped on the conductor, the insulating rod of the lower half section of the jacking rod is rotated by hands, after the wire clamp is clamped, the power switch button on the measuring device is pressed, and any remaining test button is pressed, so that the power-on detection between the wire clamp and the conductor can be carried out;

when the contact resistance needs to be measured, a power switch is switched on, then one of the buttons is pressed, at the moment, the voltage passes through a wire clamp main body frame, a conductor, a contact piece on a measurement contact body, a measurement return line, detection equipment, a grounding drainage wire and a grounding rod to form a closed circuit measurement loop, and at the moment, the direct current resistance value of the loop exists on a display of the ohmmeter; when the contact resistance exceeds a set value, an alarm is given to remind an operator to reinstall the device until the device is qualified.

Technical Field

The invention discloses a grounding device with a contact resistance detection function, belongs to the field of power system equipment maintenance, particularly relates to grounding equipment for ensuring reliable grounding of power system equipment maintenance, and is particularly suitable for high-voltage equipment maintenance and grounding protection.

Background

The grounding of the maintenance equipment is the most direct and reliable method for ensuring the safety of maintenance personnel. People must work in the protection range of the grounding wire to be safe during the maintenance process. However, if the ground wire is not hung properly, such as poor contact, residual charges of the maintenance equipment cannot be discharged completely or external inductive electricity enters the maintenance equipment, especially the inductive electricity of the equipment which is crossed and erected on the same pole has hundreds of volts or even thousands of volts, which brings great hidden danger to the safety of maintenance personnel.

The failure of effective grounding of the maintenance equipment (unqualified grounding wire installation) caused by the current stage mainly has the following two conditions:

1. the positive pressure is insufficient;

the positive pressure of the contact element refers to the force which is generated by the surfaces which are in contact with each other and is vertical to the contact surfaces, the number and the area of the contact micro-points are gradually increased along with the increase of the positive pressure, and meanwhile, the contact micro-points are transited from elastic deformation to plastic deformation; that is, the contact surface becomes smaller when the positive pressure is insufficient, and the contact resistance is increased; when the grounding wire is hung, the rotating screw of the operating rod is oxidized, rusted and rotates laboriously or the grounding wire port is not clamped or is clamped falsely due to incorrect operation.

2. The surface conduction resistance is large;

after any conductor is installed and used, an oxide layer is formed on the surface (once metal is exposed in the atmosphere, an initial oxide film layer of several micrometers is generated quickly), oil stains or other pollutants are generated, and film layer resistance is generated on the surfaces of two contact pieces; because the film layer is a poor conductor, the contact area is reduced and the contact resistance is increased along with the increase of the thickness of the film layer.

Above two kinds of circumstances all probably lead to overhauing that equipment protection is unqualified with the earth connection installation, equipment ground resistance increase causes to overhaul equipment response residual voltage to raise, threatens maintainer safety, so it is necessary to provide a new equipment and satisfies actual maintenance demand.

Disclosure of Invention

The invention aims to overcome the defects, and provides the grounding device with the function of detecting the contact resistance, which is applied to the equipment maintenance of power transmission, transformation and distribution stations of the power system, prevents overlarge grounding resistance due to unqualified mounting quality of a grounding wire for protection, induces the electric injury to people, and ensures that the maintenance equipment is reliably grounded.

The invention is realized by adopting the following technical scheme:

a grounding device with a contact resistance detection function is provided with a wire clamp, wherein the wire clamp comprises a main body frame, a drainage wire, a measuring return line, a jacking rod and a jacking block; the drainage wire and the measuring loop line are connected in parallel;

the drainage wire is connected with the main body frame, and the other end of the drainage wire is connected with a measuring device; the top pressure rod is a threaded rod, a corresponding internal thread through hole is formed in the lower portion of the main body frame, a top pressure block is movably connected to the top end of the top pressure rod and located in the main body frame, an insulating rod is connected to the lower portion of the top pressure rod, and the top pressure block can be controlled to lift through the rotating insulating rod.

The upper surface of the jacking block is provided with a dovetail groove, and a measuring contact body can be connected in a tenon-and-mortise mode through the dovetail groove.

The measuring contact body is provided with a mounting fixed block, an insulating layer and a contact piece from bottom to top respectively; the bottom of the mounting fixing block is provided with a clamping tenon matched with the dovetail groove, the side face of the contact piece is provided with a wiring hole, the wiring hole is connected with a measuring return line, and the other end of the measuring return line is connected with a measuring device.

Furthermore, the drainage wire and the measuring return line are connected in parallel, the drainage wire and the measuring return line are wrapped together through the outer sheath, the measuring return line is provided with an insulating layer, wiring of a cable is gathered and kept with certain insulation, one or three measuring return lines are provided, single-phase electricity is measured when one measuring return line is used, and each phase of three-phase electricity is measured when three measuring return lines are used.

One or three drainage wires are used for single-phase electrical grounding. Three of the three phases are used for grounding and short-circuiting, and the three phases are divided into a head end and a tail end (in a three-fork shape), wherein the three head ends are respectively used for A, B, C three phases, and the tail end is connected with a grounding rod by one connection.

Further, the outer sheath is a transparent outer sheath.

The back of the top pressure block is welded or riveted with a mouth-shaped frame, a through hole is formed in the mouth-shaped frame, a screw head is arranged at the top of the top pressure rod and is located in the mouth-shaped frame, and therefore the top pressure rod can push the top pressure block to move up and down without rotating.

The rear side of the main body frame is provided with a back fin, the back fin is provided with a connecting hole, the drainage wire is electrically connected with the main body frame through the connecting hole, and the connecting hole is a threaded hole.

The measuring device is provided with a cuboid shell, an equipment bin is arranged in the shell, a battery and detection equipment are respectively installed in the equipment bin from bottom to top, cover plates are respectively arranged above and below the equipment bin, the cover plates are fixedly connected with the shell through screws (the lower cover plate is an iron plate with the same frame size), a through observation window is arranged on the upper cover plate, the observation window is positioned above the detection equipment, 2 or 4 test buttons are arranged on one side of the cover plate, which is positioned on the observation window, wherein the single-phase electricity is tested when 2 test buttons are arranged, and the three-phase electricity is tested when 4 test buttons are arranged; one of the 2 or 4 test buttons is a power switch button, the rest are test buttons, and each test button is respectively connected with the corresponding measuring circuit line; the both ends of casing have the connecting wire nose respectively, and one end is connected on the drainage line, and one end is connected with the earth bar, and the earth bar is connected with the earth grid (or inserts the ground), plays to introduce the earth and prevent that the misdelivery voltage or the response from getting into maintenance equipment with the surplus electric charge of maintenance equipment.

The detection device is an ohmmeter with a liquid crystal display screen, the detection device is electrically connected with the shell, and the ohmmeter is a commercially available proportional measurement ohmmeter.

The battery is a lithium battery or a silver-zinc battery.

The drainage wire is a main passage for drainage and pressure relief, and the cross section of the drainage wire is 25mm ²Or 35mm²The soft copper wires are connected, the outer side of the soft copper wires is sleeved with a transparent insulating sheath, three of the head ends of the soft copper wires are respectively connected to three (A, B, C) wire clamps, the other ends of the soft copper wires are connected together to form a connection point which is used as a three-phase short circuit wire, and the connection point is led out to a grounding rod from the short circuit point and is used for grounding.

The cross section of the measuring loop line is smaller than that of the drainage wire, preferably 0.3mm ²-1mm²More preferably 0.5mm ²。

When the grounding wire contact resistance tester is used, a conductor (a copper-aluminum bar or a copper-aluminum wire connected with overhaul equipment) is placed in a main body frame, an insulating rod at the lower half section of a jacking rod is rotated by a hand, the conductor is tightly pressed in the main body frame, a power switch button on a measuring device is pressed, and any remaining test button is pressed, so that the mounted grounding wire contact resistance can be tested.

When the contact resistance needs to be measured, after a power switch is switched on, one button is pressed, at the moment, voltage passes through a test button, a measuring circuit line, a contact body, a conductor (copper bar), a wire clamp, a grounding wire and a measuring ohmmeter to form a closed measuring circuit, and at the moment, the direct current resistance value of the circuit is displayed on a display of the ohmmeter; when the contact resistance exceeds a set value, an alarm is given to remind an operator to reinstall the device until the device is qualified. Therefore, the feasible grounding of the maintenance equipment can be ensured, and the danger that the false clamping induced voltage residual of the grounding wire is too high to hurt people is avoided.

The invention has the advantages that: the invention provides a new physical structure mode by studying the defects of the existing grounding wire in the using process, a contact point insulated with the wiring body is arranged on the lower clamping top block of the wire clamp, the drainage wire (diversion) body is used as a part of a return line for measuring the grounding resistance, a measuring device is additionally arranged on the grounding pile, and the contact resistance between the grounding wire clamp and the conductor can be measured through a test button on the measuring device after the grounding wire is installed, so that the phenomena of incomplete grounding or false grounding caused by inaccurate judgment of the aging rotation power of the grounding wire clamp (sometimes mistakenly considered to be clamped because of the rotation), semi-insulating layer formed on the conductor due to oxidation dust deposition and the like to increase the grounding resistance can be prevented. The problem that whether the existing grounding wire is qualified or not cannot be judged after being installed is effectively solved. Thereby avoiding the personal safety of the maintainers threatened by the residual pressure on the overhauling equipment due to the overlarge contact resistance.

Drawings

The invention will be further explained with reference to the accompanying drawings;

FIG. 1 is a schematic perspective view of the present invention (measuring contact is inserted into top of the top pressing block through dovetail groove);

FIG. 2 is a schematic perspective view of the present invention (measuring contact is not inserted into the top block through dovetail groove);

FIG. 3 is a schematic structural diagram of the main frame of the present invention;

FIG. 4 is a schematic structural view of the top press block of the present invention;

FIG. 5 is a schematic view of the structure of the measuring device of the present invention;

FIG. 6 is a schematic view of the cover plate of the measuring device of the present invention;

FIG. 7 is a schematic view of the structure between the press rod and the press block of the present invention;

FIG. 8 is a schematic diagram of a measurement circuit of the present invention;

FIG. 9 is a schematic view of the construction of the present invention with the drainage wires and measurement circuit lines hinged together (three measurement circuit lines).

Detailed Description

Referring to fig. 1-9, a grounding device with contact resistance detection function has a wire clamp and a measuring device, wherein the wire clamp comprises a main frame 1, a drainage wire 2, a measuring return line 9, a top pressure rod 3 and a top pressure block 4; the drainage wire 2 and the measuring loop line 9 are connected in parallel with the measuring device 5 (the drainage wire 2 is connected with the measuring device shell, and the measuring loop line 9 is connected with the measuring device ohmmeter);

the drainage wire 2 is connected with the main body frame 1, and the other end of the drainage wire 2 is electrically connected with a measuring device 5; the top pressure rod 3 is a threaded rod, a corresponding internal thread through hole is formed below the main body frame 1, a top pressure block 4 is movably connected to the top end of the top pressure rod 3, the top pressure block 4 is located in the main body frame 1, an insulating rod 3-2 is connected below the top pressure rod 3, and the top pressure block 4 can be controlled to lift through rotating the insulating rod 3-2.

The upper surface of the jacking block 4 is provided with a dovetail groove 4-1, a measuring contact body 6 can be connected in a tenon-and-mortise mode through the dovetail groove 4-1,

the measuring contact body 6 is provided with a mounting fixed block 6-1, an insulating layer 6-2 and a contact piece 6-3 from bottom to top respectively; the bottom of the mounting fixing block 6-1 is provided with a tenon matched with the dovetail groove 4-1, the side surface of the contact piece 6-3 is provided with a wiring hole 6-3-1, the wiring hole 6-3-1 is connected with a measuring return line 9, and the other end of the measuring return line 9 is connected with a detection device (ohmmeter) 5-4 in the measuring device 5.

Further, the drainage wire 2 and the measuring return line 9 are connected in parallel, the drainage wire 2 and the measuring return line 9 are insulated and wrapped together through the outer sheath 10, and therefore the wiring of the cable is gathered.

Further, drainage wire 2 is in parallel with measurement return line 9 and is in the same place, and drainage wire 2 and measurement return line 9 wrap up together through the oversheath, and measurement return line 9 has the insulating layer for the line of walking of cable is put together and is kept certain insulation, and the quantity of measuring return line 9 is one or three, measures the single-phase electricity during one, measures each looks in the three-phase electricity during three.

The drainage thread 2 is divided into three and one, the drainage thread 2 is divided into a head end and a tail end, the head end is three, the tail end is one, and the head end is electrically connected with the tail end.

Further, the outer sheath is a transparent outer sheath.

The back of the top pressure block 4 is welded or riveted with a mouth-shaped frame 4-2, a through hole is formed in the mouth-shaped frame 4-2, the top of the top pressure rod 3 is provided with a screw head 3-1, and the screw head 3-1 is located in the mouth-shaped frame 4-2, so that the top pressure rod 3 can push the top pressure block 4 to move up and down without rotating.

The back fin 1-1 is arranged on the rear side of the main body frame 1, the back fin 1-1 is provided with a connecting hole, the drainage wire 2 is connected with the main body frame 1 through the connecting hole, and the connecting hole is a threaded hole.

The measuring device 5 is provided with a cuboid shell 5-1, an equipment bin 5-2 is arranged in the shell 5-1, a battery 5-3 and detection equipment 5-4 are respectively arranged in the equipment bin 5-2 from bottom to top, a cover plate 5-5 is arranged above the equipment bin 5-2, the cover plate 5-5 is fixedly connected with the shell 5-1 through screws, a transparent observation window 5-5-1 is arranged on the cover plate 5-5, the observation window 5-5-1 is positioned above the detection equipment 5-4, 2 or 4 test buttons are arranged on one side of the observation window 5-5-1 on the cover plate 5-5, wherein single-phase electricity is tested when 2 test buttons are arranged, and three-phase electricity is tested when 4 test buttons are arranged; one of the 2 or 4 test buttons is a power switch button 5-4-1, the rest are test buttons, and each test button is respectively connected with a corresponding measuring circuit line 5-4-2; the two ends of the shell 5-1 are respectively provided with a connecting lug 5-6, the connecting lug 5-6 at one side of the shell 5-1 is connected with a drainage wire 2 through an adapter 8, and the adapter 8 is connected with the detection equipment 5-4; the connecting lug 5-6 on the other side of the shell 5-1 is electrically connected with a grounding rod 7, and the grounding rod 7 is grounded to play a role in grounding and current guiding.

The detection device 5-4 is an ohmmeter with a liquid crystal display screen, the detection device 5-4 is electrically connected with the shell 5-1, and the ohmmeter is a commercially available ratio measurement ohmmeter.

The battery 5-3 is a lithium battery or a silver-zinc battery.

The drainage wire 2 is a main passage for drainage and pressure relief, and the cross section of the main passage is 25mm ²Or 35mm²The flexible copper wires are connected, the outer side of the flexible copper wires is sleeved with a transparent insulating sheath, three of the head ends of the flexible copper wires are respectively connected to three (A, B, C) wire clamps, the other ends of the flexible copper wires are connected together to form a connection point which is used as a three-phase short circuit wire, and one of the three short circuit wires is led out from the short circuit point and connected to the shell 5 of the measuring device and then connected to the ground through a ground rod.

The cross-section of the measurement loop line 9 is smaller than the drainage wire 2, preferably 0.3mm ²-1.0mm²A soft copper core insulated wire, more preferably 0.5mm ²。

When the device is used, the opening of the U-shaped main body frame 1 is clamped on a conductor, the insulating rod 3-2 of the lower half section of the jacking rod 3 is rotated by hand, the power switch button 5-4-1 on the measuring device is pressed after the wire clamp is clamped, and any remaining test button is pressed, so that the power-on detection between the wire clamp and the conductor can be carried out.

When the contact resistance needs to be measured, after a power switch is switched on, one button is pressed, at the moment, voltage passes through the wire clamp main body frame 1, a conductor, a contact piece 6-3 on the measurement contact body 6, a measurement return circuit line 9, detection equipment 5-4 and a grounding drainage wire 2 to form a closed circuit measurement loop, and at the moment, the direct current resistance value of the loop exists on a display of the ohmmeter; when the contact resistance exceeds a set value, an alarm is given to remind an operator to reinstall the device until the device is qualified. Therefore, the feasible grounding of the maintenance equipment can be ensured, and the danger that the false clamping induced voltage residual of the grounding wire is too high to hurt people is avoided.