A: Leakage current test is an electrical appliance safety test designed to detect the presence of leakage current in electrical appliances. Leakage current refers to the phenomenon of current loss on the insulating material of an electrical appliance under normal operating conditions, which may lead to safety accidents such as electric shock or fire.
2. What is the purpose of leakage current testing?
Answer: The purpose of the leakage current test is to detect whether the electrical appliances have sufficient insulation capacity to protect the safety of personal property. If there is leakage current in the appliance, it may lead to problems such as overheating and malfunctioning of the appliance, and even cause fire and other safety accidents.
3. What are the standards for leakage current testing?
A: Leakage current test standards are mainly the following:
(1) IEC60950-1: safety requirements level.
(2) IEC61010: Safety requirement level.
(3) UL508A: Safety requirement level for control panels.
(4) UL60950-1: Safety requirement levels for information technology equipment.
(5) GB4943: Security requirement levels for information technology equipment.
4. What are the methods of leakage current testing?
A: Leakage current test has the following methods:
(1) direct method: the appliance into a specific circuit, through direct measurement of the current flowing through the appliance to detect the presence of leakage current.
(2) Indirect method: By separating the wiring of the appliance and connecting the earth resistance meter between the insulated circuit of the appliance and the ground, the insulation resistance value of the circuit and the earth resistance value are measured. If the insulation resistance value is less than a certain standard, it means there is leakage current.
(3) Comparison method: the appliance to be tested and the known leakage current of the standard appliance to be compared, so as to determine whether the appliance to be tested leakage current.
5. What are the precautions for leakage current testing?
A: Leakage current test need to pay attention to the following matters:
(1) Before the test should be checked to see if the test equipment is normal, as well as whether it is in line with the relevant test standards.
(2) Interference should be eliminated as much as possible during the test to avoid testing errors.
(3) Attention should be paid to test safety during the test to avoid electrical short circuit, electric shock and other accidents.
(4) Test results need to be recorded and saved for subsequent reference use.
Expansion:
Leakage current test there is also a method called differential protection test. Differential protection test is a kind of electric power protection device test method, mainly used to detect the occurrence of faults in the power system, whether the protection device can cut off the circuit in time, so as to protect the safety of personal property. Differential protection test is mainly through the measurement of current differential to determine whether the performance of the protective device is normal. Differential protection test is a very important security test in the power system.