CN103575997A - High-voltage digital insulation resistance tester - Google Patents

Abstract

The invention discloses a high-voltage digital insulation resistance tester which comprises a high voltage generating circuit, a protecting circuit, a sampling circuit, a PWM driving circuit, an insulation resistance detecting circuit and a single chip microcomputer. The output ends of a system power supply circuit are respectively connected with the input end of the high voltage generating circuit. The output ends of a high voltage generating module are respectively connected with the input end of the PWM driving circuit and the input end of the protecting circuit. A signal output end of the protecting circuit is connected with the input end of the sampling circuit. A signal output end of the protecting circuit is connected with a signal input end of the insulation resistance detecting circuit. A signal output end of the insulation resistance detecting circuit and a signal output end of the PWM driving circuit are connected with a signal input end of the single chip microcomputer respectively. The high-voltage digital insulation resistance tester can overcome the shortcoming of traditional insulation resistance testing, meanwhile, high measuring accuracy is achieved, and stock results and measuring time can be automatically stored.

Description

High-voltage digital formula Insulation Resistance Tester

Technical field

The present invention relates to a kind of resistance meter, particularly relate to a kind of high-voltage digital formula Insulation Resistance Tester.

Background technology

The measurement of insulation resistance is the forcible inspection of item of the safety detection project of China's measurement Law regulation, Insulation Resistance Tester is commonly called as megohmmeter, it is the instrumentation of measuring insulation resistance, because testing amount is very large, complicated operation, testing result can not preserve by the large and data of man's activity automatically, in addition, also there is following shortcoming in existing megohmmeter: one, adopt pointer-type to show, deviation easily appears in reading; Two, the result such as Measuring Time and measurement data can not automatically preserve and print; Three, measuring voltage is unstable, and fluctuation causes bearing results; Four, volume is very much not convenient for carrying.

Summary of the invention

To the object of the invention is in order addressing the above problem, to provide a kind of low-power consumption, small size, to be beneficial to portable high-voltage digital formula Insulation Resistance Tester.

The present invention is achieved by the following technical solutions:

A kind of high-voltage digital formula Insulation Resistance Tester, comprise button, LCD display, system power supply circuit, high-pressure generating circuit, holding circuit, sample circuit, PWM driving circuit, power control circuit, PWM driving circuit, insulating resistor detecting circuit and single-chip microcomputer, the output terminal of described system power supply circuit is connected with the input end of high-pressure generating circuit respectively, the output terminal of described high pressure generation module is connected with the input end of described PWM driving circuit and described holding circuit respectively, the signal output part of described holding circuit is connected with the input end of described sample circuit, the signal output part of described holding circuit is connected with the signal input part of described insulating resistor detecting circuit, the signal output part of described insulating resistor detecting circuit and described PWM driving circuit is connected with the signal input part of described single-chip microcomputer respectively, the signal output part of described single-chip microcomputer is connected with the signal input part of described power control circuit and described LCD display respectively, the signal input part of described power control circuit is connected with the output terminal of described single-chip microcomputer, the output terminal of described power control circuit is connected with the input end of described system power supply circuit.

Due to inner integrated 10 the A/D modular converters of single-chip microcomputer, thus can be real-time to supply voltage through monitoring, and whether under-voltagely on LCD, show.Utilize pulse transformer and voltage-multiplying circuit to produce constant high direct voltage as test voltage source, by the dutycycle of external key control single chip computer output PWM, thereby obtain different electric pressures, this power supply is put on to product to be tested and standard loop; Power supply voltage division signal and product to be tested sampled signal are received the insulating resistor detecting circuit of single-chip microcomputer through filtering circuit, through the result of insulating resistor detecting circuit, deliver to single-chip microcomputer and carry out computing, result send LCD to show or mini-printer is printed, and also can be stored in single-chip microcomputer, in order to inquiry.

Further, on the housing of described high-voltage digital formula Insulation Resistance Tester, be provided with input wires terminal and data output wiring terminal.

As preferably, described high-voltage digital formula Insulation Resistance Tester also comprises mini-printer, and the signal input part of described mini-printer is connected with the signal output part of described single-chip microcomputer.

The invention has the beneficial effects as follows:

By adopting technique scheme, the present invention can not only solve the deficiency of traditional megger test, also has higher accuracy of measurement simultaneously, and can automatically preserve storage result and Measuring Time.

Accompanying drawing explanation

Fig. 1 is the structured flowchart of high-voltage digital formula Insulation Resistance Tester of the present invention.

Embodiment

Below in conjunction with drawings and the specific embodiments, the present invention is described in further detail:

As shown in Figure 1, high-voltage digital formula Insulation Resistance Tester of the present invention, comprise button, LCD display, system power supply circuit, high-pressure generating circuit, holding circuit, sample circuit, PWM driving circuit, power control circuit, PWM driving circuit, insulating resistor detecting circuit, mini-printer and single-chip microcomputer, the output terminal of described system power supply circuit is connected with the input end of high-pressure generating circuit respectively, the output terminal of described high pressure generation module is connected with the input end of described PWM driving circuit and described holding circuit respectively, the signal output part of described holding circuit is connected with the input end of described sample circuit, the signal output part of described holding circuit is connected with the signal input part of described insulating resistor detecting circuit, the signal output part of described insulating resistor detecting circuit and described PWM driving circuit is connected with the signal input part of described single-chip microcomputer respectively, the signal output part of described single-chip microcomputer is connected with the signal input part of described power control circuit and described LCD display respectively, the signal input part of described power control circuit is connected with the output terminal of described single-chip microcomputer, the output terminal of described power control circuit is connected with the input end of described system power supply circuit.Described high-voltage digital formula Insulation Resistance Tester also comprises mini-printer, and the signal input part of described mini-printer is connected with the signal output part of described single-chip microcomputer.

Due to inner integrated 10 the A/D modular converters of single-chip microcomputer, thus can be real-time to supply voltage through monitoring, and whether under-voltagely on LCD, show.Utilize pulse transformer and voltage-multiplying circuit to produce constant high direct voltage as test voltage source, by the dutycycle of external key control single chip computer output PWM, thereby obtain different electric pressures, this power supply is put on to product to be tested and standard loop; Power supply voltage division signal and product to be tested sampled signal are received the insulating resistor detecting circuit of single-chip microcomputer through filtering circuit, through the result of insulating resistor detecting circuit, deliver to single-chip microcomputer and carry out computing, result send LCD to show or mini-printer is printed, and also can be stored in single-chip microcomputer, in order to inquiry.

Claims (3)

1. a high-voltage digital formula Insulation Resistance Tester, comprise button, LCD display, it is characterized in that: also comprise system power supply circuit, high-pressure generating circuit, holding circuit, sample circuit, PWM driving circuit, power control circuit, PWM driving circuit, insulating resistor detecting circuit and single-chip microcomputer, the output terminal of described system power supply circuit is connected with the input end of high-pressure generating circuit respectively, the output terminal of described high pressure generation module is connected with the input end of described PWM driving circuit and described holding circuit respectively, the signal output part of described holding circuit is connected with the input end of described sample circuit, the signal output part of described holding circuit is connected with the signal input part of described insulating resistor detecting circuit, the signal output part of described insulating resistor detecting circuit and described PWM driving circuit is connected with the signal input part of described single-chip microcomputer respectively, the signal output part of described single-chip microcomputer is connected with the signal input part of described power control circuit and described LCD display respectively, the signal input part of described power control circuit is connected with the output terminal of described single-chip microcomputer, the output terminal of described power control circuit is connected with the input end of described system power supply circuit.

2. high-voltage digital formula Insulation Resistance Tester according to claim 1, is characterized in that: on the housing of described high-voltage digital formula Insulation Resistance Tester, be provided with input wires terminal and data output wiring terminal.

3. high-voltage digital formula Insulation Resistance Tester according to claim 1, is characterized in that: described high-voltage digital formula Insulation Resistance Tester also comprises mini-printer, and the signal input part of described mini-printer is connected with the signal output part of described single-chip microcomputer.

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