107 results about "Ground resistance" patented technology

The present invention relates to a grounding rod, comprising a grounding rod body (1), a grounding rod handle (2) for installing an electric hammer or a grounding cap, and a grounding rod head (3) for inserting into the ground, wherein the grounding rod handle (2) and the grounding rod head (3) are respectively arranged at two ends of the grounding rod body (1), the grounding rod body (1) is provided with a protruding spiral texture (6), the grounding rod handle (2) is provided with a grounding rod slot (5) for matching the installation of an electric hammer or a grounding cap, and the grounding rod head (3) is a cross-arranged four-edged steel knife structure (4). Compared with the prior art, the present invention has the advantages of rapid grounding, achieving grounding with a smaller grounding resistance, improving the efficiency of hammering into the ground, and being easy to carry.

A method for measuring an earth resistance in a battery charging system connected to the power grid includes, for each measurement cycle, injecting a first, alternating current, signal between a first, neutral node and a second, earth node, detecting a first voltage signal representing an electrical potential difference between the first and second node, calculating an earth resistance value as a function of the first voltage signal. Further, injecting between the first, neutral node and the second, earth node an information signal representing the calculated earth resistance value. Before the injecting the first alternating current signal: detecting one or more information signals generated by further battery charging systems connected to the power grid; determining the earth resistance value based on the information content of the received information signals; proceeding with steps a) to c) if a number of information signals lower than the pre-set limit value is detected.

The invention discloses a ground resistance detection method and system for an electrostatic management tester, and relates to the field of ground resistance detection, and the key points of the technical scheme are that Op collection nodes are arranged in parallel on a circuit, voltage data on each node are obtained through a data collection device, and preliminary processing is carried out to obtain an initial data set; an optimization detection algorithm is used for the initial data set, and voltage data are converted into comprehensive direct-current voltage and comprehensive alternating-current voltage; setting an advanced detection threshold value, judging the obtained comprehensive direct current voltage and the comprehensive alternating current voltage with the advanced detection threshold value, performing mode selection according to a judgment result, giving an alarm if the mode is abnormal, and switching to a resistance detection mode and performing voltage measurement if the mode is normal. The device is suitable for detecting grounding resistance by an electrostatic management tester, and high-quality detection is realized.

The invention is suitable for the technical field of battery insulation detection and protection, and particularly relates to a battery leakage protection method and device. According to the method, a known resistor is connected to a positive and negative electrode ground resistor in parallel, so that a second resistance value, namely a resistance value after the positive electrode ground resistor is connected with a first parallel resistor in parallel, can be accurately calculated, and the resistance value of the positive electrode ground resistor is compared with the resistance value of the first parallel resistor. Whether the real insulation resistance of the battery to the ground is too large or the protection grounding wire is lost can be determined, under the normal condition, the highest second resistance value does not exceed the resistance value of the first parallel resistor, when the second resistance value is equal to the resistance value of the first parallel resistor, the resistance value of the positive electrode to the ground resistor is represented to be infinite, and under the abnormal condition, the resistance value of the positive electrode to the ground resistor is represented to be infinite. The resistance value of the second resistor exceeds the resistance value of the first parallel resistor, abnormity caused by loss of the protection grounding wire can be determined, the insulation monitoring precision is improved, and the false alarm condition of battery detection in the high-voltage energy storage system is avoided.

The invention relates to a method and an insulation monitoring arrangement (10) for insulation monitoring of a device supplied with a DC voltage (U DC ) operated electrical installation (2) which has a first insulation resistance (R) between the positive active conductor and earth iso1 ) and a second insulation resistance (R) between the negative active conductor and earth iso2 ) and has a functional earth connection between the negative active conductor and earth by means of an earth resistance (functional earth path). The following steps are performed to carry out the procedure: Measuring an earth current flowing in the functional earth path (I E ) using a DC current measuring device (14), measuring the supply DC voltage (U DC ) using a voltage measuring device (12), calculating the first insulation resistance (R iso1 ) from the supply DC voltage (U DC) divided by the earth current (I E ) by means of a computing unit (20), wherein during the operation of the electrical system (2) the condition applies that the second insulation resistance (R iso2 ) at least one hundred times greater than the earth resistance (R) E ) is.

The present invention relates to a fast and safe cable insulation tester and a detection method thereof, comprising a plurality of multifunctional terminal hooks, an insulation connecting wire and an insulation tester, wherein the plurality of multifunctional terminal hooks are connected to the insulation tester through the insulation connecting wire, and the insulation tester comprises a housing and an internal circuit, wherein the internal circuit realizes one-key automatic detection of the insulation resistance to ground of all six-phase cables of a double cable by adding a plurality of groups of intelligent detection circuits, or detects the insulation resistance between phases one by one. After testing, it takes 4 minutes to install and remove the insulation connecting wire at one time, 4 minutes to detect the six-phase resistance to ground at the same time, and 6 minutes to detect the resistance between phases one by one, which is about 14 minutes in total. Compared with the current method, the detection time is shortened by 28 minutes, and the operation time of the climbers on the tower is shortened by 38 minutes.

The present invention discloses an insulation detection method for a charging device, comprising the following steps: A1, after the electric vehicle is connected to the charging pile, the charging pile starts to perform insulation detection, and respectively measures the DC+ to ground impedance R+ and the DC- to ground impedance R-; A2, accumulating the number of insulation detection times n, and respectively calculating the difference Δ between the measured R+, R- and the insulation impedance standard value r R+ , Δ R‑ , and then calculate Δ R+ , Δ R‑ The square values ​​of each are saved; A3, respectively R+ , Δ R‑ The square value of each and the total square of DC+ to ground resistance S R+ 、DC-to-ground resistance total square sum S R‑ Accumulate and assign the accumulated values ​​to S respectively R+ , S R‑ ; A4, then calculate the standard deviation S of DC+ impedance to ground 正 , Standard deviation of DC-to-ground impedance S 负 , and according to the calculated S 正 , S 负 The present invention can effectively avoid the risk of electric shock caused by aging of insulating materials during charging.

The invention relates an electric measuring arrangement (10) and to a measuring method both for monitoring a ground connection for an insulation monitoring device (4), which is connected to at least one active conductor (L1, L2) of an ungrounded power supply system (2) and a ground terminal (PE) of an electric installation (3), with an active loop measurement device (20), which is connectable between a ground-connection clamp (E) of the insulation monitoring device (4) and the ground terminal (PE) and has an independent excitation voltage source (UgEKE) for quantitatively determining a ground resistance (REKE) of the ground connection (6) between the insulation monitoring device (4) and the ground terminal (PE).Furthermore, the invention relates to an insulation monitoring device (30) having an electric measuring arrangement (10) according to the invention.

Provided is a home appliance employing a method for protection against electric shock when a user touches a heat exchanger. The home appliance may comprise: a heat exchanger for performing heat exchange with the outside; a first ground line connecting the heat exchanger and the ground and including a ground resistor; and a second ground line by which the heat exchanger is directly grounded on the basis of a first event by a user, and which is connected to the ground in parallel with the first ground line.

An apparatus for preventing an electric shock and a fire according to the present invention includes one or more failure detectors that have one end electrically connected to at least one of two or more power lines insulated from earth with a resistance value greater than or equal to a predetermined ground resistance value and a first neutral point having a potential between voltages of the two or more power lines, and the other end electrically connected to the earth, in which the failure detector detects a leakage current by forming a current path for the leakage current flowing from the two or more power lines or the first neutral point to the earth. According to the present disclosure, it is possible to prevent the electric shock and the occurrence of the fire due to the leakage current.

An assembly type steel rail insulation reinforcing structure is used for effectively reinforcing the insulation performance of the steel rail, improving the resistance to ground of the steel rail and effectively preventing stray current from being blocked from the source. An under-rail high-insulation pad is arranged between the bottom face of the steel rail and the plate face of the iron base plate, the two transverse sides of the under-rail high-insulation pad are each provided with a protruding part extending out of the rail bottom structure of the steel rail, the plate faces of the protruding parts on the two sides are each provided with an inserting groove and an arc-shaped groove which extend longitudinally, and the arc-shaped grooves correspond to the insulation gauge blocks on the same side in position. Insulation insertion pieces are fixedly installed on the under-rail high-insulation base plate faces through insertion grooves, insulation insertion piece bodies are provided with inner side vertical parts, outer side vertical parts and middle parts, the lower ends of the outer side vertical parts are provided with insertion parts matched with the insertion grooves, and the upper ends of the inner side vertical parts extend out of the top faces of the insulation rail gauge blocks by a certain height. The longitudinal side walls of the insulating gauge blocks are attached to the longitudinal end faces, on the sides, of the outer side vertical parts and the middle parts, and the inner walls of the outer side vertical parts and the inner walls of the middle parts are attached to the side walls of the lower portion of the rail bottom structure and the adjacent partial slopes.

The utility model relates to the technical field of transformer grounding structures, in particular to a transformer grounding structure which comprises flat steel bodies arranged in a vertical state, the lower portions of the flat steel bodies are inserted into the ground and located on one side of a telegraph pole body, the upper portions of the flat steel bodies are located on the ground and provided with a plurality of grounding cable connecting points, and the number of the flat steel bodies is multiple. The plurality of flat steel bodies are distributed along the circumferential side of the telegraph pole body, the upper portions and the lower portions of the plurality of flat steel bodies are locked on the telegraph pole body through the locking hoop rings, the hoop rings are made of conductive materials, the plurality of flat steel bodies are connected in parallel to be grounded, the contact area between the flat steel bodies and the ground is increased, and therefore the grounding resistance in the initial stage of installation of the grounding structure is reduced. The flat steel body is welded on the ground, so that the adaptability of the grounding structure to environment change is further enhanced, the contact area between the flat steel body and the ground can be further increased by welding the conductive anchor cable at the bottom of the flat steel body, the coverage area is wider, and the adaptability to the environment is further enhanced.

The invention relates to a method and an insulation monitoring arrangement (10) for insulation monitoring of an electrical system (2) operated with a direct supply voltage (UDC), which has a first insulation resistance (Riso1) between the positive active conductor and earth and a second insulation resistance (Riso2) between the negative active conductor and earth, as well as a functional earthing between the negative active conductor and earth by means of an earthing resistance (path of the functional earthing).To carry out the method, the following steps are carried out: measuring an earth current (IE) flowing in the functional earth path by means of a DC current measuring device (14), measuring the DC supply voltage (UDC) by means of a voltage measuring device (12), calculating the first insulation resistance (Riso1) from the DC supply voltage (UDC) divided by the earth current (IE) by means of a computing unit (20), wherein during operation of the electrical system (2) the condition applies that the second insulation resistance (Riso2) is at least one hundred times greater than the earth resistance (RE).

The present invention relates to the field of electricity safety technology, and specifically to a zero-ground resistance monitoring device and method. It includes: an energy storage element, a charging circuit, a discharging circuit, a sampling circuit, a shaping filter circuit and a control circuit. The energy storage element is charged by the charging circuit, and the zero-crossing moment of the power supply system is monitored in real time by the shaping filter circuit and the control circuit. When the control circuit detects that the voltage between the neutral line and the ground line is zero, the discharge circuit is used to discharge the energy storage element, and the voltage at both ends of the energy storage element during the discharge process is detected; and the sampling circuit measures the current value in the discharge circuit when the energy storage element is discharged; finally, the detected voltage and current values ​​are fed back to the control circuit, and the control circuit calculates the equivalent resistance value between the neutral line and the ground line according to the obtained voltage and current values, so as to realize online measurement and monitoring of the grounding resistance of the distribution system.

The utility model discloses a pincerlike grounding resistance tester, and particularly relates to the technical field of pincerlike grounding resistance testers, the pincerlike grounding resistance tester comprises a resistance tester assembly, the bottom surface of a resistance tester body is provided with a lengthened pulling assembly, and the pincerlike grounding resistance tester only needs to manually pull out an adjusting holding rod, so that the pincerlike grounding resistance can be tested. And after the adjusting holding rod is drawn to a certain length, the adjusting screw rod is screwed back again to fix the adjusting holding rod at the current position, so that the overall length of the pincerlike grounding resistance tester can be conveniently adjusted, the working radius of the pincerlike grounding resistance tester can be increased by changing the overall length of the resistance tester, and meanwhile, the trigger can be pulled through the pull rope, so that the working efficiency is improved. The pull rope passes through the rope passing groove, and the rope passing groove can enable the pull rope to pull the trigger towards the inner side, so that an electric power worker can press the trigger to separate the clamp head, the electric power worker can conveniently use the clamp-shaped grounding resistance tester to test a narrow and deeper area of an electric box, and the practicability is higher.

1. The name of this design product: Split-type ground resistance online tester. 2. Purpose of this design product: used as a ground resistance tester to test ground resistance. 3. The key point of the design of this product lies in its shape. 4. The picture or photo that best illustrates the design points: usage status diagram 7.

The utility model discloses a wind turbine generator lightning protection grounding structure suitable for a rock geologic structure. The wind turbine generator lightning protection grounding structure comprises a vertical grounding electrode communicated with a fan foundation. Grounding drill holes with the number corresponding to that of the vertical grounding electrodes are evenly formed in the periphery of the fan foundation in the circumferential direction, the grounding drill holes penetrate through the high-resistance rock stratum and communicate with the low-resistance rock stratum to form a high-resistance rock stratum section and a low-resistance rock stratum section, rock stratum cracks are formed in the wall face of the high-resistance rock stratum section, and the vertical grounding electrodes are inserted into the grounding drill holes. The bottom end of the vertical grounding electrode penetrates through the grounding drill hole to be inserted into the low-resistance stratum, and graphene transition bodies are filled between the vertical grounding electrode and the high-resistance stratum section of the grounding drill hole and in stratum fractures of the high-resistance stratum section at high pressure. According to the utility model, the resistance value of the grounding resistor of the wind turbine generator in rock geology can be effectively reduced, so that the grounding requirement of the wind turbine generator can be better met, the normal operation of wind turbine generator equipment and the personal safety of personnel can be ensured, and the construction work amount and the material cost can be effectively reduced.

A mobile machine is operatively attached to a ripper to perform a ripping operation of the terrain substrate by traveling over the terrain surface. The mobile machine may be connected to sensors to measure the ground resistance that opposes the direction of travel of the mobile machine during the ripping operation. If the ground resistance is disproportionate, the mobile machine may perform a shaft adjustment sequence by adjusting one or more of a pitch actuator and a lift actuator to move the ripper relative to the terrain and reduce the ground resistance.

The invention discloses an electromagnetic shielding film and a circuit board, the electromagnetic shielding film comprises a shielding layer, a first surface of the shielding layer is provided with a projection structure, and after the electromagnetic shielding film is laminated with a circuit board substrate provided with an OSP grounding structure through the projection structure, under a preset grounding window size, the grounding resistance of the electromagnetic shielding film is less than 800m omega. The electromagnetic shielding film can be ensured to maintain proper grounding resistance on the OSP grounding structures of different circuit board substrates, so that the grounding effect of the electromagnetic shielding film on the OSP grounding structures of the circuit board substrates is relatively good, and the electromagnetic shielding requirement of the circuit board can be met.

The utility model provides a floating prevention device for a ground source heat pump buried pipe, which belongs to the field of ground source heat pumps and comprises a floating prevention plate and four supporting and adjusting mechanisms used for positioning the floating prevention plate and capable of horizontally adjusting the floating prevention plate, and each supporting and adjusting mechanism comprises a screw capable of penetrating through the floating prevention plate. A supporting disc abutting against the ground is fixed to the bottom of the threaded rod, a fixing cone capable of being inserted into the ground is fixed to the bottom of the supporting disc, the threaded rod is in threaded connection with a supporting nut and a positioning nut, and the floating resisting plate can be adjusted to the horizontal position by adjusting the supporting nut and the positioning nut. According to display of the bubble level, the supporting nut and the positioning nut are accurately adjusted, it is ensured that the floating resisting plate reaches the absolute horizontal state, and therefore it is ensured that the upper end of a pipe opening of the buried pipe is in the horizontal state, good conditions are provided for follow-up pipeline threaded connection, and the problem that due to unsmooth thread meshing, pipeline installation is inconvenient is solved.

The present invention belongs to the technical field of power transmission line equipment, and discloses an auxiliary mechanism for measuring ground resistance. Bolts pass through pole towers, drain plates and nuts in sequence. The auxiliary mechanism for measuring ground resistance includes an insulating sleeve and a limiter. The middle part of the insulating sleeve is movably connected so that the insulating sleeve can be sleeved on the bolt to separate the drain plate from the bolt. Two limiters are provided, and the two limiters are respectively arranged at the two ends of the insulating sleeve along the axial direction of the bolt. The middle part of the limiter is movably connected and can be sleeved on the bolt. The limiter is provided with a bending part so that the limiter can be bent in the direction away from the bolt along the radial direction of the bolt to separate the drain plate from the pole tower and the nut. The limiter is made of insulating material. The auxiliary mechanism for measuring ground resistance provided by the present invention can stably keep the drain plate and the pole tower insulated, so as to realize the ground resistance measurement on the basis of not completely disassembling the grounding down conductor.

The invention belongs to the technical field of lightning protection detection equipment, and particularly relates to an urban building lightning protection detection device, which comprises a grounding megger main body, a megger E terminal wire, a megger P terminal wire, a megger C terminal wire and two conductive insertion rods, the bottom end of the grounding megger main body is fixedly connected with a hollow box, the bottom end of the hollow box is hermetically connected with a bottom cover, and the bottom cover is fixedly connected with the grounding megger main body. The bottom cover is fixedly connected with the outer wall of the bottom end of the hollow box through bolts. The urban building lightning protection detection device not only has the function of quickly cleaning the surface of a grounding resistance test point, but also has the functions of damage detection and convenient winding and unwinding of the megger E terminal wire, the megger P terminal wire and the megger C terminal wire, so that the accuracy of the detection result of the lightning protection detection device can be ensured; and the reliability and convenience of use of the lightning protection detection device are also improved, the hidden danger of lightning stroke buried in a building is avoided, the safety of personnel and equipment in the building can be ensured, and the detection intensity of workers is reduced.

The invention belongs to the technical field of wind power grounding configuration, and particularly relates to a configuration device and method suitable for wind power grounding in complex mountainous regions, and the device comprises an inner ring grounding grid, an outer ring grounding grid, and a vertical grounding electrode assembly. A conductive strip is arranged between the adjacent vertical grounding electrode assemblies of the inner ring grounding grid and the outer ring grounding grid. The vertical grounding electrode assembly comprises a welding seat, an electrode column and a supporting cover. The lower side of the welding seat is fixedly connected with an electrode column; a supporting cover is arranged on the outer side of the electrode column; and a resistance reducing material is filled between the supporting cover and the electrode column. Through the arrangement of the inner-ring grounding grid, the outer-ring grounding grid and the vertical grounding electrode assemblies distributed in an array mode, the current of a tower drum can be rapidly guided into the ground, the grounding resistance can be greatly reduced through the resistance reducing material, the influence of geological movement, biological activity or humidity change after construction is small, the high-efficiency attaching contact state with an electrode column can be kept for a long time, and the construction efficiency is improved. And the service life of the grounding device is prolonged.

To provide a switching power supply device complying with an electric shock protection class 2 that is able to effectively prevent noise current flowing in a ground resistor.SOLUTION: A voltage generated in a primary-side main winding 24 (1) becomes a noise source, resulting in generation of a noise current Icom (1) that flows out to a ground line 32 through unstable-potential stray capacitors Cf1 to Cf3 and a noise current Icom (2) that flows out to the ground line 32 through a secondary-side stray capacitor Cy2. An insulating transformer 22 has a secondary-side auxiliary winding 40(2) one end of which is connected to a secondary-side stable potential line 14; and a capacitance forming region 42c of a wiring pattern 42 connected to the other end of the secondary-side auxiliary winding 40(2) and a capacitor forming region 44c of a primary-side stable potential line 12 are disposed opposite to each other to form a wiring-pattern stray capacitor Ch. When a predetermined level of current flows through the wiring-pattern stray capacitor Ch, a magnitude of the current obtained by combining the noise currents Icom (1) and Icom (2) can be restricted to a reference value or less.SELECTED DRAWING: Figure 1

The utility model provides a pincerlike grounding resistance tester, and relates to the field of resistance testing. The mounting structure is spliced behind the tester body, the contact structure is mounted at the front end of the mounting structure through a supporting head and an outer groove, the U-shaped contact structure is made of a flexible rubber material, three anti-slip strips are fixed above the inner side of the contact structure, and the section of each anti-slip strip made of the rubber material is of a triangular structure. When data is temporarily recorded, the tester body is controlled to automatically incline, so that the circuit is embedded into the contact structure, and if the circuit is thicker, the contact structure fixes the circuit by virtue of an elastic anti-slip manner and is in anti-slip contact with the anti-slip strip, so that the fixing effect on the tester body is improved, the tester body is prevented from slipping off, the tester body is conveniently and temporarily released from the hand, and data recording is performed; the clamp-shaped grounding resistance tester solves the problem that when a common clamp-shaped grounding resistance tester needs to temporarily record data, the clamp-shaped grounding resistance tester needs to be taken down and then record the data, so that the frequent and rapid testing speed is influenced.

The present application relates to the field of power grid protection system protection technology, and in particular to a method for evaluating and warning the hazard of low-amplitude direct lightning strikes in distribution networks. The method comprises: measuring the maximum value of the grounding resistance, the tower height and the tower spacing of the target tower in the distribution network; calculating the corrected grounding shunt coefficient corresponding to each tower according to the maximum value of the grounding resistance of the target tower, the tower height and the tower spacing; obtaining the lightning current amplitude of the distribution network, and calculating the tower top overvoltage of the target tower according to the corrected grounding shunt coefficient, the maximum value of the tower grounding resistance and the lightning current amplitude; when the tower top overvoltage is greater than or equal to the preset tolerance voltage threshold of the target tower, outputting a warning that the distribution network is subject to severe direct lightning strike hazards; otherwise, no warning is output. It aims to solve the problem of how to accurately calculate the tower top overvoltage of the tower.

The invention discloses a grounding resistance tester for electromechanical installation engineering, and relates to the technical field of electromechanical installation engineering, the grounding resistance tester comprises a tester main body, the outer side of the tester main body is rotatably connected with a box body, the side surface of the box body is rotatably connected with a box door, the inner side of the box body is provided with a winding assembly, and the winding assembly comprises a connecting unit arranged at the inner side of the box body. A first winding drum and a second winding drum are rotationally connected to the inner side of the box body, clamping plates are symmetrically and movably connected to the inner sides of the first winding drum and the second winding drum, a wire harness is inserted into the inner sides of the first winding drum and the second winding drum and clamped and fixed through the clamping plates, and the wire harness is stored when the first winding drum rotates. According to the wire harness winding device, by arranging the winding assembly, the rotation speed ratio of the first winding drum to the second winding drum is two fifths, it is ensured that synchronous winding of wire harnesses of different lengths or diameters is completed, and the ending work of a test can be rapidly finished.

The invention discloses a tower horizontal grounding electrode impact effective length calculation method, and the method comprises the steps: building a three-dimensional horizontal grounding electrode model according to the structure size, material attribute and burying condition of a horizontal grounding electrode of a 220kV power transmission line tower; arranging a lightning current excitation source at one end of a grounding electrode of the three-dimensional horizontal grounding electrode model, and simulating lightning impulses with different amplitudes, waveforms and action time; carrying out electromagnetic field simulation calculation, outputting a voltage peak value, a grounding current peak value and current distribution of the grounding electrode, and calculating the impact effective length of the horizontal grounding electrode according to the impact grounding resistance and the geometric parameters of the grounding electrode; adjusting the size and the structure of the grounding electrode to obtain the effective impact length of the horizontal grounding electrode under different conditions so as to optimize the three-dimensional horizontal grounding electrode model; and performing simulation verification on the optimized three-dimensional horizontal grounding electrode model, and if the impact grounding resistance does not meet the standard value, continuing to adjust and optimize and repeating the simulation verification process until the impact grounding resistance meets the standard requirement.

The utility model provides a quick insulation test plug handle of a logging instrument, which is characterized by comprising a handle body, one side of the handle body is in threaded connection with a 41-core aviation socket through a three-combination screw, the other side of the handle body is sequentially sleeved with a 32-core plug and a handle outer cylinder, and the handle outer cylinder is connected with a guide block through a cross countersunk head screw; the device is applied to detection and maintenance of the logging instrument, not only can realize quick connection test of the logging instrument and diagnostic equipment, but also can ensure that the shell of the logging instrument is communicated with the ground wire of the diagnostic equipment, judges whether the cable cores are damaged by measuring the ground resistance of each cable core, and can assist testers in quickly locking the fault position of the instrument.