Search

CN-121995269-A - Clamp-on meter head for measuring leakage current with variable caliber based on non-return-to-zero principle

CN121995269ACN 121995269 ACN121995269 ACN 121995269ACN-121995269-A

Abstract

The invention discloses a clamp-on meter head for measuring variable caliber leakage current based on a non-return-to-zero principle, which particularly relates to the technical field of leakage detection, comprising a base, wherein a clamping detection assembly and a current measurement assembly are arranged on the base, the clamping detection assembly comprises a supporting plate fixedly arranged on a base, a traction frame adjustable along the vertical direction, a first deflection plate, a second deflection plate and two clamping plates, wherein the two clamping plates are respectively and correspondingly arranged at the free ends of the first deflection plate and the second deflection plate, and clamping grooves for accommodating circuits are formed in opposite sides of the two clamping plates. According to the invention, the adjusting plate with the strip-shaped adjusting holes is arranged at the end part of the clamping plate, and the bolt fixing structure is matched, so that the mounting height of the clamping plate on the deflection plate can be accurately adjusted, and the flexible adaptation of lines with different diameters can be realized by combining the design of the clamping grooves with arc cross sections, so that the diversified measurement requirements of industrial large-caliber cables, civil thin wires and the like can be met without changing clamp heads.

Inventors

  • Yuan Guanchun
  • Gan Zhanglin
  • SUN XIANQING

Assignees

  • 湖北瑞城建设有限公司

Dates

Publication Date
20260508
Application Date
20260304

Claims (7)

  1. 1. The clamp-on meter head for measuring the variable caliber leakage current based on the non-return-to-zero principle comprises a base (1) and is characterized in that a clamping detection assembly and a current measurement assembly are arranged on the base (1); The clamping detection assembly comprises a supporting plate (2) fixedly arranged on the base (1), a traction frame (3) adjustable along the vertical direction, a first deflection plate (4), a second deflection plate (5) and two clamping plates (6); The two clamping plates (6) are respectively and correspondingly arranged at the free ends of the first deflection plate (4) and the second deflection plate (5), clamping grooves (7) for accommodating circuits are formed in the opposite sides of the two clamping plates (6), and the cross sections of the clamping grooves (7) are arc-shaped; the current measurement assembly comprises a deflection rod (13), a current sensor (15) and a current display meter (14); The deflection rod (13) is fixedly arranged in the middle of the base (1), one end of the deflection rod extends to the outer side of the base (1) and is connected with the current display meter (14), the current sensor (15) is fixedly arranged on the deflection rod (13) and is electrically connected with the current display meter (14), the current sensor (15) is fixedly connected to the base (1) in an inserting mode, and the detection end of the current sensor corresponds to the clamping areas of the two clamping plates (6); The base (1) is provided with a mounting cavity (10), a driving assembly is arranged in the mounting cavity (10), the driving assembly is used for driving the traction frame (3) to lift along the vertical direction, and then the first deflection plate (4) and the second deflection plate (5) are driven to deflect around the limiting shaft (8), so that the two clamping plates (6) are close to or far away from each other, and clamping and positioning of lines with different sizes are realized.
  2. 2. The non-return-to-zero principle based variable aperture leakage current measurement clamp meter head of claim 1, wherein the driving assembly comprises a lining cushion block (11) embedded and installed in the installation cavity (10) and two symmetrically arranged electric push rods (12); The lining cushion block (11) is tightly attached to the inner wall of the installation cavity (10), the two electric push rods (12) are respectively fixed at two ends of the lining cushion block (11), and the output shafts of the electric push rods (12) extend upwards along the vertical direction and are fixedly connected with the bottom of the traction frame (3) after penetrating through the top wall of the base (1).
  3. 3. The clamp-on meter head for measuring the variable caliber leakage current based on the non-return-to-zero principle according to claim 1, wherein a limiting shaft (8) is fixedly embedded into the top end of the supporting plate (2), one ends of the first deflection plate (4) and the second deflection plate (5) are respectively provided with a hollow block (9), the hollow blocks (9) are sleeved on the limiting shaft (8) and are rotationally connected with the limiting shaft (8), the traction frame (3) is positioned in the middle of the supporting plate (2), and two side walls of the traction frame are respectively matched with one ends, far away from the hollow blocks (9), of the first deflection plate (4) and the second deflection plate (5) through sliding connection structures.
  4. 4. The clamp-on meter head for measuring the variable caliber leakage current based on the non-return-to-zero principle according to claim 1 is characterized in that inner bushings (16) are fixedly embedded in the two hollow blocks (9), the inner bushings (16) are made of wear-resistant insulating materials, and the inner bushings (16) are tightly sleeved on the limiting shaft (8) and are in rotary fit with the limiting shaft (8).
  5. 5. The clamp-on gauge head for measuring the variable caliber leakage current based on the non-return-to-zero principle according to claim 1 is characterized in that one end, far away from the clamping groove (7), of each of the two clamping plates (6) is provided with an adjusting plate (17), each of the adjusting plates (17) is provided with an elongated adjusting hole, and the clamping plates (6) are detachably fixed at the free ends of the first deflection plate (4) and the second deflection plate (5) through bolts penetrating through the adjusting holes; the mounting height of the clamping plates (6) can be changed by adjusting the position of the bolt in the adjusting hole, so that the clamping range between the two clamping plates (6) can be adjusted.
  6. 6. The clamp-on meter head for measuring the variable caliber leakage current based on the non-return-to-zero principle according to claim 1 is characterized in that the axis of the limiting shaft (8) is perpendicularly intersected with the symmetrical center lines of the two clamping plates (6), and the detection center of the current sensor (15) and the center of the clamping groove (7) are positioned in the same vertical plane.
  7. 7. The clamp-on meter head for measuring the variable caliber leakage current based on the non-return-to-zero principle according to claim 3, wherein the sliding connection structure comprises sliding grooves (18) formed in two side walls of the traction frame (3) and shaft pins fixed at the end parts of the first deflection plate (4) and the second deflection plate (5); the sliding groove (18) extends along the height direction of the traction frame (3), the shaft pin is slidingly embedded into the sliding groove (18), and the shaft pin is in clearance fit with the inner wall of the sliding groove (18).

Description

Clamp-on meter head for measuring leakage current with variable caliber based on non-return-to-zero principle Technical Field The invention relates to the technical field of leakage detection, in particular to a clamp-on meter head for measuring variable caliber leakage current based on a non-return-to-zero principle. Background The leakage current is used as a core evaluation index of the insulation performance and electricity safety of an electrical system, and the accurate detection of the leakage current is directly related to the safe operation in multiple fields such as industrial production, building power distribution, civil electrical appliances and the like. The current is the residual current which is separated from the closed loop of the phase line and the zero line and abnormally leaks to the ground, the equipment shell or other unexpected paths due to the problems of insulation breakage, aging, damp, equipment failure or abnormal lap joint of the line in the electric loop, and if operators cannot timely detect and process the residual current, the safety accidents such as electric shock, equipment burnout and even fire disaster are extremely easy to be caused, and great loss is brought to production and life. The core requirement of the leakage current measurement is that on the premise of not damaging a circuit structure and not interrupting power supply, the leakage current is monitored in real time, so that the insulation state of a circuit/equipment is judged, the leakage fault is checked, the effectiveness of a leakage protection device (RCD/ELCB) is verified, and the electricity safety is ensured. Currently, the mainstream measuring tools comprise a clamp-on leakage ammeter, a leakage tester and the like, and the measuring principle of the main measuring tools is divided into two types: The instrument is based on the traditional zero resetting/reference zero clearing principle, and the instrument needs to execute zero clearing operation manually or automatically before measurement, so as to eliminate the influence of jaw remanence, ambient stray magnetic field and zero drift of the instrument on a measurement result, and finally takes a zero cleared numerical value as a fixed measurement reference, and the reading directly reflects the current instantaneous current value. The leakage current is a microampere-level weak signal, a real slow fluctuation signal and steady residual leakage are easy to filter in the forced zero clearing process, so that measurement readings are small, even the potential risk of chronic leakage is missed, real-time working conditions such as environment magnetic field change, jaw and line relative position deviation cannot be dynamically adapted after the standard is fixed, measurement errors are large, only instantaneous single-point values can be obtained, current change trend cannot be recorded, scene requirements such as intermittent leakage checking, long-term running state monitoring and the like are difficult to meet, and fourth, the resolution capability of external interference such as power frequency interference and magnetic field of an adjacent line is weak, false readings or false alarms are easy to generate, and judgment efficiency of operators is influenced. The other type is a non-return-to-zero principle, and is characterized in that an operator is not required to execute forced zero calibration in the measurement process, the offset of a measurement reference, the difference value of a historical fluctuation value and a real-time signal are reserved and continuously recorded, and various defects of the return-to-zero principle are overcome through the advantages of dynamic tracking of the reference offset, fidelity small signals, trending measurement, anti-interference correction and the like. However, the clamp meter head based on the non-return-to-zero principle still has obvious technical short plates, wherein most of product calibers are fixed and only can be matched with lines of specific sizes, so that an operator needs to replace special clamp heads when encountering lines of different diameters, the working efficiency is seriously affected, few products with caliber adjusting functions have the problems of complex adjusting structure, complex operation, insufficient clamping stability and the like, the line positioning precision is low, the accuracy of detecting leakage current is further affected, meanwhile, the relative position design of a current sensor of part of products and a clamping area is unreasonable, the measuring error is further increased, and the diversified measuring requirements of the lines of different diameters and complex environments cannot be met. Disclosure of Invention In order to overcome the defects in the prior art, the invention provides a clamp-on meter head for measuring variable caliber leakage current based on a non-return-to-zero principle, which aims to solve the problems in the prior art. The invent