The difference between megohmmeter and multimeter measuring insulation resistance
The megohmmeter is specially used to measure insulation resistance, because it can output high voltage of more than a few hundred volts, and can measure the insulation degree of electrical appliances more accurately.
The output voltage of the multimeter is very low, even the output voltage of the R×10k block of the pointer multimeter is not high, and it is possible to measure the insulation resistance of some low-voltage ordinary electrical appliances.
If a multimeter is used to measure the insulation resistance of electrical equipment, its resistance value may be infinite, and the actual working conditions of electrical equipment are hundreds of volts or thousands of volts. At this time, the insulation resistance displayed by the measurement is no longer infinite, and may become very small.
Therefore, to measure the insulation resistance of electrical equipment, the instrument should be selected according to the rated voltage level of the electrical equipment. Usually, a megohmmeter is used to measure the insulation resistance.
