CN202853820U - High voltage isolation switch contact finger pressure test instrument - Google Patents

Abstract

The utility model discloses a contact finger pressure testing instrument for a high-voltage isolating switch, which comprises a mold matching the contact shape of a high-voltage isolating switch in normal use, a contact pressure sensor, an acquisition and amplification circuit, a single-chip microcomputer and a display; the contact pressure sensor It is detachably embedded in the mold, and one end exposes the mold; the signal output end of the contact pressure sensor is connected to the signal input end of the acquisition amplifier circuit through the RS232 data line, and the signal output end of the acquisition amplifier circuit is connected to the signal of the A/D conversion circuit in the single chip microcomputer The input end, the signal output end of the A/D conversion circuit in the single-chip microcomputer is connected to the signal input end of the processor in the single-chip microcomputer, and the signal output end of the processor in the single-chip microcomputer is connected to the display. The utility model can test the pressure of the contact finger of the high-voltage isolating switch, so as to solve the problem of heating of the high-voltage isolating switch contact due to insufficient pressure of the contact finger of the high-voltage isolating switch; the test is convenient, the accuracy is high, and the display is intuitive.

Description

High voltage isolating switch finger pressure test instrument

technical field

The utility model relates to a testing instrument for testing the finger pressure of a high-voltage isolating switch.

Background technique

At present, the heating problem of high-voltage isolating switch contacts will lead to melting of the hot parts of the contacts, increasing the number of power outages and affecting the operation structure of the power grid. After the analysis and statistics of the heating problems of the existing high-voltage isolating switches, it is found that the heating of the contact fingers of the isolating switch accounts for more than 80% of the total heating problems, and the contact heating caused by insufficient contact pressure of the contact parts of the isolating switch accounts for more than 80% of the total heating problems. To more than 60% of the heating defects of the isolating switch fingers, therefore, the key to reducing the heating of the high-voltage isolating switch is to ensure the pressure of the isolating switch fingers. At present, only by testing the contact resistance of the knife switch circuit to judge the contact condition of the contact part, roughly judge whether the pressure of the contact finger of the isolating switch is qualified, and there is a lack of preventive monitoring means. In order to meet the requirements of item 9.3.1 of "Guidelines for State Maintenance of Power Transmission and Transformation Equipment of Hebei Electric Power Company" and "Check the contact pressure of dynamic and static contacts" and "Guidelines for State Diagnosis of Power Transmission and Transformation Equipment of Hebei Electric Power Company" 11.2.2 "Isolation switch Touch finger pressure does not meet the technical conditions" detection requirements, adding isolating switch state detection means to fill the blind spot where the touch finger pressure cannot be measured during work, and there is an urgent need for instruments to detect touch finger pressure.

Utility model content

The purpose of this utility model is to solve the above-mentioned problems in the prior art, and provide a high-voltage isolating switch finger pressure testing instrument, which has a simple structure, convenient and accurate testing, and intuitive display.

In order to achieve the above object, the technical solution of the utility model is: a high-voltage isolating switch finger pressure testing instrument, which includes a mold that matches the shape of the contact of the high-voltage isolating switch in normal use, a contact pressure sensor, and an acquisition and amplification circuit , single-chip microcomputer and display; the contact pressure sensor is detachably embedded in the mold, and one end of the mold is exposed; the signal output end of the contact pressure sensor is connected to the signal input end of the acquisition amplifier circuit through the RS232 data line, and the signal output end of the acquisition amplifier circuit is connected to The signal input end of the A/D conversion circuit in the single-chip microcomputer, the signal output end of the A/D conversion circuit in the single-chip microcomputer is connected to the signal input end of the processor in the single-chip microcomputer, and the signal output end of the processor in the single-chip microcomputer is connected to the display.

The display described above adopts a liquid crystal display.

The above-mentioned contact pressure sensor adopts a piezoresistive sensor.

When in use, the mold of the utility model is clamped between the contact fingers of the isolating switch, and the display can directly display the pressure of the contact fingers of the isolating switch. The utility model can test the pressure of the contact finger of the high-voltage isolating switch, so as to solve the problem of heating of the contact finger of the high-voltage isolating switch caused by insufficient pressure in advance. The utility model has the advantages of convenient testing, high accuracy and intuitive display; the utility model has the advantages of simple structure, small volume, light weight and convenient portability. Only the mold itself can be replaced according to the different types of stylus, and the use cost is low.

Description of drawings

Fig. 1 is the circuit block diagram of the present utility model;

Fig. 2 is the schematic circuit diagram of the utility model.

Detailed ways

As shown in Fig. 1 and Fig. 2, this embodiment includes a mold 3, a piezoresistive pressure sensor 2, an acquisition and amplification circuit 7, a single-chip microcomputer 8 and a liquid crystal display 9 that match the shape of the high-voltage isolating switch contact during normal use. The piezoresistive sensor 2 is clamped and fixed in the mold 3 . 4 is a contact finger, and 1 is a contact finger spring. The piezoresistive sensor 2 is a piezoresistive structure composed of rheostat R11, rheostat R12, rheostat R13 and rheostat R14, the acquisition amplifier circuit 7 adopts the OP07 type operational amplifier U1, the single-chip microcomputer 8 adopts the C805lF020 single-chip microcomputer U2, and the liquid crystal display 9 Select HSl2864 graphics dot matrix liquid crystal display U3. The signal output terminal of the piezoresistive pressure sensor 2 is connected to the input terminals 2 and 3 of the operational amplifier U1 through the RS232 data line 5 and the resistors R2 and R3, and the output terminal 6 of the operational amplifier U1 is connected to the signal input of the single chip microcomputer U2 through the resistor R5 Terminal P1.0 pin, the analog pressure value is converted into a digital value through the A/D conversion circuit in the single-chip microcomputer U2, and then the digital value is converted into data that can be displayed by the display through the processor in the single-chip microcomputer U2, and the signal of the single-chip microcomputer U2 Output P0.0 pin, P0.1 pin, P0.2 pin, P0.3 pin, P0.4 pin, P0.5 pin, P0.6 pin and P0.7 pin output to graphic dot matrix LCD through data bus The signal pin input terminal DB0 pin, DB1 pin, DB2 pin, DB3 pin, DB4 pin, DB5 pin, DB6 pin, DB7 pin, RS pin and R/W pin of the display U3 are displayed by the graphic dot matrix liquid crystal display U3. Pin 8 of operational amplifier U1 is connected to one end of sliding rheostat R8, pin 6 is connected to the other end of sliding rheostat R8, pin 1 is connected to +9V power supply, pin 4 is connected to -9V power supply, pin 2 is connected to pin 6 through resistor R4; sliding rheostat R8 Connect the center tap of the +9V supply. The 16-pin and 17-pin of the single-chip microcomputer U2 are respectively connected to the input terminal of the integrated chip U4 whose model is 74HC00, and the signal output terminal of the integrated chip U4 is connected to the E-pin of the liquid crystal display U3; A crystal oscillator circuit composed of a crystal oscillator T. The reset pin RST of the liquid crystal display U3 is connected to the ground through the capacitor C2 one way, and the other way is connected to the power supply VCC through the resistor R10.

The foregoing embodiments are only preferred and exemplary, and those skilled in the art can, for example, adopt other types of operational amplifier U1, other types of single-chip microcomputers and other types of liquid crystal displays according to the description of this patent, as long as their functions can realize amplification, Only AD conversion and display are required, which are all covered by the protection scope of this patent.

Claims (3)

1. a high-voltage isolating switch sensing finger pressure tester device is characterized in that: the high voltage isolation switch contact shape was complementary when it comprised with normal use the mould, contact pressure sensor, collection amplifying circuit, single-chip microcomputer and display; Contact pressure sensor removably is embedded in the mould, and an end exposes mould; The signal output part of contact pressure sensor connects the signal input part that gathers amplifying circuit by the RS232 data line, the signal output part that gathers amplifying circuit connects the signal input part of A/D change-over circuit in the single-chip microcomputer, the signal output part of A/D change-over circuit connects the signal input part of single-chip microcomputer inner treater in the single-chip microcomputer, and the signal output part of single-chip microcomputer inner treater connects display.

2. high-voltage isolating switch sensing finger pressure tester device according to claim 1 is characterized in that: described display employing liquid crystal display.

3. it is characterized in that according to claim 1 or 2 described high-voltage isolating switch sensing finger pressure tester devices: described contact pressure sensor adopts piezoresistive transducer.

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