It is important to use material sampling to evaluate the quality of power equipment. In the equipment testing report

the simple judgement of qualified or unqualified is given to each testing index

which leads to the waste of a large number of testing data. In order to make more in-depth use of test data and understand the quality of equipment

based on adaptive grey clustering

combined with a number of testing indicators

a grading evaluation method for the overhead insulated wire is proposed. The consideration of test results under specific test conditions can simplify the evaluation system. The qualified power equipment quality can be classified into “ excellent ”and“ good”grades. . At the same time

the correlation analysis of test data under specific test conditions can simplify the evaluation index system. It deepens the utilization of the data in the equipment testing report

which is helpful for the testing personnel to understand the equipment quality more accurately and provides reference for the equipment procurement.