Insulation can either be solid, liquid, or gaseous dielectric materials that prevent the flow of electricity between points of different potential. Insulation testing is performed to determine the integrity of the insulation. This usually consists of applying a high potential voltage to the item and measuring the
leakage current that may flow to ground. Excessive leakage current is an indication of dielectric breakdown and/or impending failure. Insulation may weaken over time at a rate tightly related to the operating time and temperature of the operation. Therefore, these tests are run periodically to track the
insulation deterioration. Insulation testing, the most common electrical testing performed, can be reformed by applying a direct current (dc) or alternating current (ac) voltage. The type and value of the voltage determine whether the test is considered non-destructive or destructive. The higher the voltage the more destructive the test. Usually, destructive tests are only run one time in the factory to verify the initial strength of the insulation, and non-destructive tests are run as acceptance and maintenance tests to erasure deterioration from the original value. Both the do and ac tests are "go no-go" tests. In addition, he do test can indicate the amount of deterioration and forecast the remaining time for safe operation by comparing the leakage current and test voltage to values from previous tests.
Wuhan Huayi electric power manufactures different insulation testers with different models, which can meet your all kinds of test requirements.
The output voltage is from 100V to 25KV. They are digital and portable, suitable for testing insulation resistance on-site. High accuracy and performance, reading DAR and PI directly. It is a necessary testing tool for every electrical engineer engaged in electric commissioning service.