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What are the working principles and main uses of insulation resistance testers?

:2024-03-28 09:32:51:

The working principle of the insulation resistance tester is mainly based on Ohm's law. There is a power supply inside the tester that can generate DC high voltage. When the high voltage is applied to the tested object, the current flowing through the tested object is measured, and then the resistance of the tested object is calculated using Ohm's law. This resistance value is the insulation resistance. Usually, the higher the insulation resistance value, the better the insulation performance.

The insulation resistance tester not only has the function of measuring resistance, but also has the function of measuring absorption ratio and polarization index. Absorption ratio refers to the ratio of the insulation resistance value of an insulator when a DC voltage is applied for 60 seconds to the insulation resistance value at 15 seconds. Polarization index refers to the ratio of the insulation resistance value of an insulator when a DC voltage is applied for 10 minutes to the insulation resistance value at 1 minute. These ratios can further reflect the performance status of insulators.

Therefore, insulation resistance testers play an important role in the insulation performance testing of electrical equipment, helping to timely detect potential insulation problems and prevent the occurrence of electrical accidents.

The main purpose of an insulation resistance tester is to measure the insulation resistance of large transformers, transformers, generators, high-voltage motors, power capacitors, power cables, lightning arresters, and other equipment. In addition, it can also measure micro resistance and has advantages such as accurate measurement, convenient reading, and good stability.

Insulation resistance tester is an indispensable measuring instrument for industrial enterprises in the fields of power, postal and telecommunications, communication, mechanical and electrical installation and maintenance, as well as the use of electricity as industrial power or energy. By testing the insulation resistance, it is possible to determine whether the insulation performance of electrical equipment is qualified, thereby preventing safety accidents such as electric shock or equipment damage caused by a decrease in equipment insulation performance.

Therefore, insulation resistance testers play an important role in the installation, handover, and preventive testing of electrical equipment, and are important tools to ensure the safe and stable operation of equipment.


ZC-430C Digital insulation resistance meter also known as megohmmeter, high voltage insulation resistance tester, etc., for the insulation resistance test. The instrument has a large LCD screen gray backlit display, data storage, data access, alarm, automatic shutdown and other

functions. At the same time, it also has the function of measuring DC voltage, AC voltage, absorption ratio and polarization index of DC 

voltage. It is suitable for measuring the resistance value of various insulating materials and the insulation resistance of transformers, motors, cables and electrical equipment.At the same time, it can output a variety of different voltage levels with the step-adjusting voltage function.

Kvtester Electronics Technology Co.,Ltd. is a high-tech enterprise specializing in power testing, testing, research and development, production, and sales of testing equipment. It has been engaged in the electrical testing industry for many years, and its products are of high quality. We welcome customers to come and purchase. Service hotline: 0086-27-81778799, to learn more, visit the official website:

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