The equipment for electrical safety performance test is in rapid development of modern science technology; all kinds of electrical and electronic equipment are into all fields of social life and become an important symbol of social civilization and progress. All kinds of electrical appliances and electronic equipment are used in both urban and rural areas and have rapid popularization, which brings great convenience for production. But the widespread use of electrical appliances and electronic equipment also brings increased accidents and brings harm to life and property, electric shock casualties and electrical fires are common. Therefore, the use safety of electrical appliances and electronic equipment is an important problem; it becomes the leading position of the factors that decide the product quality. Safety standards become one of the most important technical standards.
Electrical safety performance test mainly has withstanding voltage test, insulation resistance test, leakage current test and grounding resistance test. Brief introduction:
- Withstanding voltage test is one of the main methods to inspect the withstand voltage capacity of electrical appliances, electrical equipment, electrical wiring and electrical safety appliance. It has power frequency withstand voltage test and DC withstand voltage test. The test voltage of power frequency withstand voltage test is one time or several times than the tested voltage, it will not be lower than 1000V. The test time: it is 1 minute for porcelain and liquid as the main insulation equipment; it is 5 minutes for the organic solids as the main insulation equipment; it is 3 minutes for voltage transformer; it is 10 minutes for oil immersed power cable. It can find local defects, moisture and aging of insulation if electrical equipment does withstand voltage test. AC withstand voltage test: Do the test voltage in 2.5 times or above of the tested equipment voltage, it starts from the point of dielectric loss’s thermal breakdown, it can effectively find the weakness of local free and insulation aging. Due to the voltage is mainly divided by capacitive in AC voltage; it can effectively expose the defects of equipment insulation.
It is mainly to achieve the following purposes:
i. Detect insulation withstand voltage capacity from working voltage or overvoltage capacity.
ii. Check the insulation of electric equipment manufacture or inspect quality.
iii. Exclude the insulation damage because of raw material, processing or transport; reduce the product early failure rate.
iv. Detect the electric clearance and creep age distances of insulation.