Nearly every high-voltage equipment prior to delivery to the customer will undergo a test related to C and tan-d for a final quality control. Such tests are in generally conducted at the frequency for which the equipment is designed.
Full Description
The reasons for the tests are firstly that excessively high losses (= high tan-d) may cause a thermal breakdown or, secondly, the manufacturer of a specific equipment knows the typical magnitudes which can be tolerated and which provide information about the quality of newly manufactured equipment; and these measurements can also serve for a comparison with later preventive