BDV ofter e few days later

Discussion in 'The Projects Forum' started by wire272, Mar 10, 2013.

  1. wire272

    Thread Starter New Member

    Mar 10, 2013
    Hello everyone

    There is a need of your help and your expertise to explain a strange situation which happened in our production. Would you please advise us what could cause the following problem:

    A month ago we had a production of a round copper wire with the following specifications:

    Wire size : 2.65 mm (0.1043 Inches)
    Grade : 2L
    Enamel type: PE:642/40P+ OC.720/34S (Elantas)
    oven temp. : 430°C
    Tangent Delta : 201.4

    The first day of production all the tests passed with the best results. The breakdown voltage (VBD) was 5.5 kV up to 9 kV. After two weeks sitting in the warehouse we had a dramatic failure. The break down voltage dropped on majority of the spools. On some of the test results we had a breakdown voltage maximum 2.5 kV and even as low as 0.7 kV. We did not notice anything unusual in the production and we were not able to pin point to anything unusual. Your help is greatly appreciated and looking forward to hear from you. Our factory is Placed near sea. (Humidity is about 60% to 80%).

    Best regards
  2. StayatHomeElectronics

    Well-Known Member

    Sep 25, 2008
    Talk to the maker of your enamel insulation. They would probably have some idea of what tests to run in order to find out why it failed. Too many possibilities to diagnose on a forum.