Dongguan Longwei Electronic Technology Co., Ltd

LW (LONGWEI) always adhere to the "quality first, customer first, keep improving" !

Home > News > Content
What Is A Pressure Tester
- Apr 23, 2018 -

Withstand voltage tester is also called electrical insulation strength tester or dielectric strength tester, also have said dielectric breakdown device, dielectric strength tester breakdown device, experimental apparatus of high pressure and high pressure, pressure tester and so on. Test the ability of an electrical insulating material to withstand the ability to withstand voltage by applying a specified ac or dc high voltage to the electrically charged part and the non-charged part (usually the outer shell). Electrical appliances in the long-term work, not only inherit the rated working voltage of the role, but also cause a short period of time in the process of operation under higher than the rated working voltage of the overvoltage function (overvoltage value may be higher than the rated working voltage of several times). Under the action of these voltages, the internal structure of the electrical insulating material will change. When the overvoltage intensity reaches a certain value, the insulation of the material will be broken through, the electrical appliances will not operate normally, and the operator may be electrocuted and endanger the personal safety.

The main test indexes of electrical safety include ac/dc resistance, insulation resistance, leakage current, grounding resistance, etc. The ac/dc voltage withstand test is one of the important indexes to check the electrical safety performance of the products under the actual working conditions. Seen on the market at present the hipot tester adopts GB4706 IEC1010 (equivalent) standard, use more is the single structure of the bench test index test instrument, can't meet the needs of the user needs to multi-index comprehensive test; And the hipot tester on the market at present is one of the traditional test methods, test precision is not high, and the adopted technology of the main performance indicators has a certain gap with foreign advanced level, the can't completely meet the current development of the need of the electrical safety performance test. Therefore, it is of great significance to study the application of advanced technology and the pressure test system with better performance indicators.

The pressure tester is mainly used for the voltage withstand test of polyethylene insulated power cable, and it can also be used for the insulation withstand test of large power transformer. It is a new method to test the voltage of power cable with ultra-low frequency voltage.

Basic principle of pressure tester.

The basic principle of withstand voltage tester: add a higher than normal working voltage in the equipment to be tested on insulator, and continue for a period of time, the insulation good enough if the meantime, in the above voltage is only a small leakage current is produced. If a device being tested insulators within the prescribed period of time, the leakage current to keep within the prescribed scope, can determine the device under test can be safe operation under normal operating conditions.

The test system has three modules: program-controlled power module, signal acquisition and conditioning module and computer control system.

Structure and composition of pressure tester.

(1) the lifting part.

Voltage regulating transformer, booster transformer and booster part power switch and cut-off switch.

The voltage of 220V is connected to the voltage regulating transformer. The user can control the output voltage of the booster transformer simply by adjusting the regulator.

(2) control part

Current sampling, time circuit, alarm circuit composition. When the control part receives the start signal, the instrument is immediately connected to the power supply. When receiving the measured circuit current exceeds the set value and the sound and light alarm immediately cut off the power of the booster circuit. Cut off the boost circuit power when receiving reset or time to signal.

(3) display circuit

The display shows the output voltage of the booster transformer. Shows the current value of the current sampling part, and the time value of the time circuit is usually the countdown.

(4) the above is the traditional structure of the voltage resistance tester. With electronic technology and single chip, computer technology develops rapidly; The programmable voltage withstand tester has also developed rapidly in recent years. The difference between the program and the traditional pressure-resistant device is mainly the boost part. SPC pressure meter high pressure booster is not through the mains by voltage regulator to adjust, but by single chip computer control to create a 50 hz or 60 hz sine wave signal through the power amplifier circuit for amplifying booster, the output voltage is controlled by single chip computer, the other part principle and traditional pressure meter.