CN204086403U - A kind of conductor resistance and resistivity test device thereof - Google Patents

Abstract

The utility model discloses a conductor resistance and resistivity measuring device, which is characterized in that it comprises a constant current source (1), an input and output unit (3), an AD acquisition module (2) comprises a single chip microcomputer (2-1), a sampling Resistance (2-2), measured conductor (2-3), sampling resistance AD acquisition module (2-4), measured conductor AD acquisition module (2-5); sampling resistance AD acquisition module (2-4) includes Sampling the first voltage dividing resistor (2-4-1), sampling the second voltage dividing resistor (2-4-2), sampling resistor comparison amplifier (2-4-3), sampling resistor AD chip (2-4-4 ); the measured conductor AD acquisition module (2-5) includes the measured first voltage divider resistor (2-5-1), the measured second voltage divider resistor (2-5-2), the measured conductor comparison amplifier ( 2-5-3), the measured conductor AD chip (2-5-4), the utility model reduces labor intensity, light weight, small size, can be completed by a single person, powerful, automatic operation, accurate analysis and judgment The material of the conductor under test.

Description

A conductor resistance and resistivity measuring device

Technical field:

The utility model relates to a conductor resistance and a resistivity measuring device thereof, belonging to the technical field of power system substation maintenance.

Background technique:

In the handover and condition maintenance of power equipment, the measurement of the resistance and resistivity of conductor circuits such as transformers and switches is an effective means to detect the status of equipment. It can find out whether there are design and manufacturing defects in the equipment, and problems such as shoddy goods. However, the current measurement of conductor resistance and resistivity still adopts the traditional method, that is, the current-voltage method. The on-site calculation requires a lot of work, and due to the influence of the accuracy of the meter and the error of the personnel's eyes, the measurement error is large and the work is difficult. low efficiency.

Utility model content:

The purpose of the utility model is to overcome the deficiencies of the above-mentioned prior art and provide a measuring device that greatly reduces the labor intensity and the weight and volume of the measuring equipment, which can be completed by a single person, has powerful functions, can be automatically operated, and can be accurately measured. Conductor resistance and its resistivity measuring device for analyzing and judging the material conditions of transformers and switch conductors.

The purpose of this utility model can be achieved through the following measures: a conductor resistance and resistivity measuring device thereof, is characterized in that it comprises a constant current source, the constant current source is connected to an AD acquisition module, the AD acquisition module is connected to an input and output unit, and the AD acquisition The module includes single-chip microcomputer, sampling resistor, measured conductor, sampling resistor AD acquisition module, and measured conductor AD acquisition module; the sampling resistor AD acquisition module includes sampling first voltage dividing resistor, sampling second voltage dividing resistor, sampling resistor comparison amplifier, sampling resistor Resistance AD chip; the measured conductor AD acquisition module includes the measured first voltage divider resistor, the measured second voltage divider resistor, the measured conductor comparison amplifier, and the measured conductor AD chip; the sampling resistor is connected to the constant current source and the sampling first The voltage dividing resistor, the sampling second voltage dividing resistor, the sampling first voltage dividing resistor and the sampling second voltage dividing resistor are connected to the sampling resistor comparison amplifier, and the sampling resistor comparison amplifier is connected to the sampling resistor AD chip; the measured conductor is connected to the constant current source and the measured conductor respectively. The first voltage dividing resistor to be tested, the second voltage dividing resistor to be tested, the first voltage dividing resistor to be tested, and the second voltage dividing resistor to be tested are connected to the comparative amplifier of the conductor under test, and the comparative amplifier of the conductor under test is connected to the AD chip of the conductor under test. The resistance AD chip and the measured conductor AD chip are respectively connected with the single-chip microcomputer.

In order to further realize the purpose of the utility model, the input and output unit includes a printer, a memory, a display unit, and a key, and the single-chip microcomputer is respectively connected to the printer, the memory, the display unit, and the key.

Compared with the prior art, the utility model can produce the following positive effects: the utility model adopts an integrated design, which greatly reduces the labor intensity, greatly reduces the weight and volume of the measuring equipment, and can be measured by a single person, with powerful functions. It can be operated automatically, and can accurately analyze and judge the material conditions of transformers and switch conductors. It is more suitable for on-site use, making complex and cumbersome conductor material tests easier and more convenient, and greatly improving the efficiency of related work, so as to provide timely detection of transformers. defects, to ensure the safe and stable operation of equipment and lay a solid foundation.

Description of drawings:

Fig. 1 is a block diagram of the utility model;

Figure 2 is the circuit schematic diagram of the AD acquisition module.

The specific embodiment: below in conjunction with accompanying drawing, the best embodiment of the present utility model is described in detail:

Embodiment: a conductor resistance and resistivity measurement device (see FIGS. 1-2 ), which includes a constant current source 1 , an AD acquisition module 2 and an input and output unit 3 . AD acquisition module 2 includes single-chip microcomputer 2-1, sampling resistance 2-2, measured conductor 2-3, sampling resistance AD acquisition module 2-4, measured conductor AD acquisition module 2-5; sampling resistance AD acquisition module 2-4 Including sampling first voltage dividing resistor 2-4-1, sampling second voltage dividing resistor 2-4-2, sampling resistor comparison amplifier 2-4-3, sampling resistor AD chip (ICL7135) 2-4-4; The conductor AD acquisition module 2-5 includes the measured first voltage dividing resistor 2-5-1, the measured second voltage dividing resistor 2-5-2, the measured conductor comparison amplifier 2-5-3, and the measured conductor AD chip (ICL7135) 2-5-4. The sampling resistor 2-2 is respectively connected to the constant current source 1, the sampling first voltage dividing resistor 2-4-1, the sampling second voltage dividing resistor 2-4-2, the sampling first voltage dividing resistor 2-4-1, the sampling second The two voltage divider resistors 2-4-2 are connected to the sampling resistor comparison amplifier 2-4-3, and the sampling resistor comparison amplifier 2-4-3 is connected to the sampling resistor AD chip (ICL7135) 2-4-4; the measured conductors 2-3 are respectively Connect the constant current source 1, the first voltage dividing resistor 2-5-1 to be tested, the second voltage dividing resistor 2-5-2 to be tested, the first voltage dividing resistor 2-5-1 to be tested, and the second voltage dividing resistor to be tested The piezoresistor 2-5-2 is connected to the tested conductor comparison amplifier 2-5-3, and the tested conductor comparison amplifier 2-5-3 is connected to the tested conductor AD chip (ICL7135) 2-5-4. The input and output unit 3 includes a thermal printer 3-1, a memory 3-2, a display unit 3-3, and a button 3-4. The single-chip microcomputer 2-1 is respectively connected to the sampling resistor AD chip (ICL7135) 2-4-4, and the conductor to be tested. AD chip (ICL7135) 2-5-4, thermal printer 3-1, memory 3-2, display unit 3-3, keys 3-4.

The utility model adopts 50A and 100A constant current sources, and the current output of the constant current source 1 is stable and reliable, the ripple and noise are small, it is convenient for single-chip control, the power supply is small in size, and its heat dissipation performance is good. There is a stable sampling resistor connected to the conductor under test, the sampling resistor and the conductor under test are connected in series in the constant current circuit, the voltage signals of the two are collected through two AD modules, and the cross-sectional area S (unit: mm ² ), length L (unit m), temperature T (unit °C) and the temperature coefficient of the material (copper or aluminum), the single-chip microcomputer calculates the resistance and resistivity of the measured conductor according to the above parameters and the collected voltage signal value, and then The measured data is stored in a memory that is not easily lost when power is off, and displayed through a display unit. The thermal printer can print the current measurement data and historical measurement data, which is convenient for viewing and saving the results.

As shown in Figure 2, the constant current source 1 outputs 50A or 100A current, which flows through the stable sampling resistor 2-2 inside the device and the measured conductor 2-3 outside the device, and the two are connected in series. The voltage of the sampling resistor 2-2 is divided by the sampling first voltage dividing resistor 2-4-1 and the sampling second voltage dividing resistor 2-4-2, realizing the attenuation of the voltage signal, and sampling the second voltage dividing resistor 2-4 -2 The voltage signal at both ends passes through the sampling resistor comparison amplifier 2-4-3 to amplify the signal to 0.65V-1.9V, and then input to the sampling resistor AD chip (ICL7135) 2-4-4, the same as the measured conductor 2-3 The voltage is divided by the measured first voltage dividing resistor 2-5-1 and the measured second voltage dividing resistor 2-5-2, and the voltage signal at both ends of the measured second voltage dividing resistor 2-5-2 is measured The conductor comparison amplifier 2-5-3 amplifies the signal to 0.65V-1.9V, and then inputs it to the measured conductor AD chip (ICL7135 ) 2-5-4, at this time the single-chip microcomputer (2-1) pairs the sampling resistor AD chip (ICL7135 )2-4-4 and the tested conductor AD chip (ICL7135) 2-5-4 send a start signal, the sampling resistor AD chip ICL71352-4-4 and the tested conductor AD chip (ICL7135) 2-5-4 start working, The input analog voltage signal is converted into digital quantization values, and then output to the single chip microcomputer 2-1 for processing, which is the whole working process of the AD acquisition module 2.

The input and output unit 3 includes a thermal printer 3-1, a memory 3-2, a display unit 3-3, and keys 3-4. The display unit 3-3 displays interface information such as parameters and results to be input, and the key 3-4 cooperates with the display unit 3-3 to complete the cross-sectional area S (unit mm ² ), length L (unit m), temperature T (unit °C) And the input of parameters such as the temperature coefficient of material (copper or aluminum), single-chip microcomputer 2-1 calculates according to the voltage signal value of these parameters and sampling resistance AD chip 2-4-4, measured conductor AD chip 2-5-4 collection output Conductor resistance and the resistivity when 20 DEG C, the single-chip microcomputer 2-1 stores the result in the memory 3-2 again, at this moment, operate the button 3-4, and the thermal printer can print the current measurement data and the history measurement data, convenient View and save results. Memory 3-2 is AT24C512, which does not lose information when the power is off. When the measuring device is powered on, enter the historical measurement data query interface through the key 3-4 and the display module 3-3, and you can view the historical measurement data. At this time Operation button 3-4, thermal printer 3-1 can still print the result.

Claims (2)

1. a conductor resistance and resistivity test device thereof, it is characterized in that it comprises constant current source (1), constant current source (1) connects AD acquisition module (2), AD acquisition module (2) connects input-output unit (3), and AD acquisition module (2) comprises single-chip microcomputer (2-1), sample resistance (2-2), measured conductor (2-3), sample resistance AD acquisition module (2-4), measured conductor AD acquisition module (2-5); Sample resistance AD acquisition module (2-4) comprises sampling first divider resistance (2-4-1), samples the second divider resistance (2-4-2), sample resistance comparison amplifier (2-4-3), sample resistance A/D chip (2-4-4); Measured conductor AD acquisition module (2-5) comprises tested first divider resistance (2-5-1), tested second divider resistance (2-5-2), measured conductor comparison amplifier (2-5-3), measured conductor A/D chip (2-5-4); Sample resistance (2-2) connects constant current source (1) and sampling the first divider resistance (2-4-1) respectively, samples the second divider resistance (2-4-2), sample the first divider resistance (2-4-1), sample the second divider resistance (2-4-2) and connect sample resistance comparison amplifier (2-4-3), sample resistance comparison amplifier (2-4-3) connects sample resistance A/D chip (2-4-4); Measured conductor (2-3) connects constant current source (1) and tested first divider resistance (2-5-1), tested second divider resistance (2-5-2) respectively, tested first divider resistance (2-5-1), tested second divider resistance (2-5-2) connect measured conductor comparison amplifier (2-5-3), measured conductor comparison amplifier (2-5-3) connects measured conductor A/D chip (2-5-4), and sample resistance A/D chip (2-4-4), measured conductor A/D chip (2-5-4) are connected with single-chip microcomputer (2-1) respectively.

2. a kind of conductor resistance according to claim 1 and resistivity test device thereof, it is characterized in that described input-output unit (3) comprises printer (3-1), storer (3-2), display unit (3-3), button (3-4), single-chip microcomputer (2-1) connects printer (3-1), storer (3-2), display unit (3-3), button (3-4) respectively.