CN216449640U

CN216449640U - Cross four-wire system of voltage wire

Info

Publication number: CN216449640U
Application number: CN202121036052.6U
Authority: CN
Inventors: 陈锡辉; 任光前
Original assignee: Shenzhen Xinweier Electronics Co Ltd
Current assignee: Shenzhen Xinweier Electronics Co Ltd
Priority date: 2021-05-14
Filing date: 2021-05-14
Publication date: 2022-05-06
Anticipated expiration: 2031-05-14

Abstract

The utility model provides a voltage line crossed four-wire system, which comprises a connecting cable, a measuring four-wire clamp and a measuring circuit board, wherein one end of the connecting cable is connected with the measuring four-wire clamp, and the other end of the connecting cable is connected with the measuring circuit board, and the utility model has the beneficial effects that: the structure is simple, the cost is low, interference signals induced by the current line in the voltage line are cut off greatly, and the signal-to-noise ratio of a front-end input measurement signal is improved; the system of crossing four lines of the voltage line can be applied to mobile measurement, when the system is applied to fixed position measurement, the system is convenient to use, when the areas of two areas are adjusted to be approximately equal, the same-frequency alternating current mutual inductance signals can be mostly offset, and high measurement precision can be obtained when small impedance is measured; if the voltage lines are crossed, interference signals induced in the alternating magnetic field in the two voltage loops after crossing are also in opposite phases and can be offset, and the signal-to-noise ratio of a useful measurement signal to an external interference signal is also improved.

Description

Cross four-wire system of voltage wire

[ technical field ] A method for producing a semiconductor device

The utility model relates to the technical field of four-wire system measurement, in particular to a voltage wire crossing four-wire system.

[ background of the utility model ]

The high-precision detection of the weak voltage signal has wide application in the fields of scientific research, engineering manufacturing, aerospace, military, medicine and the like. However, the amplitude of the weak voltage signal is very small, and interference of noise signals and other interference signals may occur in the actual measurement process, so that the weak voltage signal is difficult to be accurately detected during measurement, or a part of the weak voltage signal may not be detected.

In an instrument for precisely measuring impedance, a four-wire system measurement is often used to improve measurement accuracy. When weak voltage on weak resistance (capacitive reactance, inductive reactance) of milliohm or microohm level is measured, alternating magnetic flux is generated by a loop formed by measuring current, mutual inductance voltage noise interference is generated on a voltage loop by the alternating magnetic flux generated by the loop, the interference signal and a useful signal are same-frequency signals and cannot be reduced by filtering measures, and the mutual inductance interference signal is often far larger than the useful signal during measurement of the weak resistance (impedance), so that the measurement accuracy is very low. Therefore, how to reduce the interference of the same-frequency mutual inductance signal on the voltage signal in the measuring loop, improve the signal-to-noise ratio of the input end of the testing instrument, enable the weak voltage signal to be detected with high accuracy, and solve the problem of urgent need.

[ Utility model ] content

The utility model aims to solve the problem of common-frequency mutual inductance interference signals generated by a current four-wire system measuring current wire in a voltage wire loop, and provides a novel voltage wire crossing four-wire system.

The utility model is realized by the following technical scheme:

the utility model provides a voltage line crossing four-wire system, includes connecting cable, measures four-wire anchor clamps, measurement circuit board, connecting cable one end with measure four-wire anchor clamps and be connected, the connecting cable other end is connected with measurement circuit board.

Further, the connecting cable is composed of 2 current lines and 2 voltage lines.

Furthermore, the current wires or the voltage wires are crossed and arranged in the fixing area of the measuring four-wire clamp to form two current and voltage coupling areas, the magnetic flux influence voltages of the two areas are opposite, and induction signals caused by alternating magnetic fields of the current wires automatically cancel each other.

Further, the current line or the voltage line is a 2-core cable.

Furthermore, the four-wire measuring clamp is a four-wire clamp or a four-wire meter pen or a four-wire wiring terminal or a four-wire probe.

The utility model has the beneficial effects that:

(1) the structure is simple, the cost is low, interference signals induced by the current line in the voltage line are cut off greatly, and the signal-to-noise ratio of a front-end input measurement signal is improved;

(2) the voltage line crossing four-wire system can be applied to mobile measurement, is more convenient when applied to fixed position measurement, can mostly offset common-frequency alternating current mutual inductance signals when the areas of two areas are approximately equal to each other, and can obtain high measurement precision when measuring small impedance;

(3) if the voltage lines are crossed, interference signals induced in the alternating magnetic field in the two voltage loops after crossing are also in opposite phases and can be offset, and the signal-to-noise ratio of a useful measurement signal to an external interference signal is also improved.

[ description of the drawings ]

FIG. 1 is a schematic diagram of a cross-over four-wire system of voltage lines according to the present invention;

reference numerals: 1. a connecting cable; 11. a current line; 12. a voltage line; 2. measuring a four-wire clamp; 3. and measuring the circuit board.

[ detailed description ] embodiments

The utility model is further described with reference to the accompanying drawings and the detailed description:

as shown in fig. 1, a voltage line crossing four-wire system includes a connection cable 1, a measuring four-wire jig 2, and a measuring circuit board 3, wherein one end of the connection cable 1 is connected to the measuring four-wire jig 2, and the other end of the connection cable 1 is connected to the measuring circuit board 3.

Preferably, the connection cable 1 consists of 2

current lines

11, 2 voltage lines 12.

Preferably, the current lines 11 or the voltage lines 12 are crossed in the fixed area of the four-wire jig 2 to form two current-voltage coupling areas, the magnetic flux induced voltages of the two areas are opposite, the induced signals caused by the alternating magnetic field of the current lines automatically cancel each other, when the magnetic flux induced voltages of the two areas are U1 and U2, respectively, when the two areas are not crossed, the interference voltage UA | | | U1| + | U2|, when the two areas are crossed, the interference voltage UB | | | U1| - | | - | U2| |, obviously UB | < UA, and when the two areas are equal, UB | 0.

Preferably, the current line 11 or the voltage line 12 is a 2-core cable, and the intersection of the two lines is cross-connected to obtain a better compensation effect.

Preferably, the measuring four-wire clamp 2 is a four-wire clamp or a four-wire meter pen or a four-wire terminal.

Appropriate changes and modifications to the embodiments described above will become apparent to those skilled in the art from the disclosure and teachings of the foregoing description. If a plurality of serially connected measured targets are measured, the intersection of voltage lines or current lines can be carried out according to the scheme, and the interference of co-frequency mutual inductance signals is reduced. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and variations of the present invention should fall within the scope of the claims of the present invention. Furthermore, although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

1. The utility model provides a voltage line four-wire system that intersects which characterized in that: the device comprises a connecting cable, a measuring four-wire clamp and a measuring circuit board, wherein one end of the connecting cable is connected with the measuring four-wire clamp, the other end of the connecting cable is connected with the measuring circuit board, and the connecting cable consists of 2 current wires and 2 voltage wires; the current lines or the voltage lines are crossed and wired in a fixed area of the four-wire measuring clamp to form two current and voltage coupling areas, the magnetic flux influence voltages of the two areas are opposite, and induction signals caused by alternating magnetic fields of the current lines automatically cancel each other.

2. A voltage line crossing four wire system as claimed in claim 1, wherein: the current wire or the voltage wire is a 2-core cable.

3. A voltage line crossing four wire system as claimed in claim 1, wherein: the four-wire measuring clamp is a four-wire clamp or a four-wire meter pen or a four-wire wiring terminal or a four-wire probe.