What Kinds of Insulation Resistance Tester Are There_ What's the Difference?

What is an insulation resistance tester

Insulation resistance tester, i.e. intelligent double display insulation resistance tester (two gears), adopts embedded industrial single chip microcomputer real-time operating system, and the perfect combination of digital analog pointer and digital segment code display. It is also known as digital insulation resistance tester, megohmmeter, intelligent insulation resistance tester, etc. This series of meters has the characteristics of multiple voltage output levels, large capacity, strong anti-interference, dual-purpose AC and DC, simple operation, various measurement results, anti power failure function and so on. It is an ideal test instrument for measuring the insulation resistance of large capacity transformers, mutual inductors, generators, high-voltage motors, power capacitors, power cables, lightning arresters and so on.

Characteristics of insulation resistance tester1. High output power, strong carrying capacity and strong anti-interference ability.2. The shell of the meter is made of high-strength aluminum alloy. The machine is equipped with equipotential protection ring and fourth-order active low-pass filter, which can effectively shield the external power frequency and strong electromagnetic field. As the output short-circuit current is greater than 1.6mA, the test voltage can easily rise to the rated value of the output voltage. For low resistance measurement, because the proportional method is adopted, the voltage drop does not affect the test accuracy.

3. Without manual work, it is powered by battery, and the range can be changed automatically. The clear panel operation and LCD display make the measurement very convenient and fast.4. The output short-circuit current of this meter can be measured directly without on load measurement.Function of insulation resistance tester

Insulation resistance tester is an electrical measuring instrument used to measure the direct action of insulation resistance and simulate the indication, and its unit is expressed in M ; Terminal voltage - the voltage between the terminal of the instrument line and the grounding terminal; Measuring terminal knob - insulation resistance meter is used to connect the measured terminal. The measuring terminal button of the insulation resistance meter shall be marked with line terminal button L, grounding terminal button E and shielding terminal button g respectively.Principle of insulation resistance tester

The insulation resistance tester mainly uses a voltage to excite the tested device or network, then measures the current generated by the excitation, and uses Ohm's law to measure the resistance. For example, these electrical testers apply a much higher voltage when making resistance measurements than the ohmmeter function equipped on the digital multimeter (DMM). The voltage range used by the megger is usually from 50V to up to 5kV; The voltage of a typical digital multimeter is generally less than 10 v. For insulation test, the range of resistance value to be measured is large, the upper limit can reach 10t , and the required voltage is higher.

Main functions of insulation resistance tester1. Repair faulty componentsThe technician uses the test to check the high insulation resistance between the conductor and the ground or adjacent conductors. By testing the insulation resistance of different components in the system (transformer, switchgear, conductor and motor), the technician can isolate and repair the faulty components.

2. Improve system performanceBefore energizing the system, the insulation test is used to verify that it is sound and can improve the performance of the system.3. Find manufacturing process problems and equipment defects

Insulation test can find manufacturing process problems and equipment defects, which can not be found before equipment failure. In the EU, the test is mandatory, even for the smallest civil systems.What kinds of insulation resistance tester are there_ differenceInsulation resistance tester can be divided into manual type and electric type according to the number of operation modes; The insulation resistance tester can be divided into digital display and pointer type according to the display mode; The insulation resistance tester can be divided into band absorption ratio and polarization index, without absorption ratio and polarization index, etc.

At the same time, there are many choices according to the output voltage. The common output voltage can reach 10000v at most, and the measurement range is also very large. At present, the maximum measurement resistance value can be as high as 1999g .In addition, according to the gear range and function, the insulation resistance tester can be divided into a variety of equipment, which can be customized and selected according to the voltage requirements of customers. It should be noted that the data measured by the insulation resistance tester with large short-circuit current will be stable.Application of insulation resistance tester

Insulation resistance tester, commonly known as megger or megger, is widely used to measure the insulation resistance of generators, motors, power transformers, wiring, electrical appliances and other electrical devices (such as control, signal, communication and power cables). They are often used in routine maintenance procedures to indicate changes in insulation resistance of motors over months or years. Large changes in insulation resistance may indicate potential faults. Therefore, it is necessary to calibrate the megger regularly to ensure that the instrument itself does not change over time.