The possibility of flash-overs: Due to low high-frequency efficiency in the insulator system rather than lack of unit factor of safety or poor string gradient

Much has been written about the electrical characteristics of insulators but comparatively little about the limitations of the air as determining their performance. In this paper the limitations of the insulating systems due to their low efficiency at high frequency is discussed. Attention is called to the necessity of raising the high frequency efficiency in order to eliminate flash-overs, also the advisability of considering string gradient as a means of improving the unit factor of safety rather than as an essential in itself in order that one characteristic in the insulator may not be improved at the expense of another or more important essential. The possibility of taking advantage of increased flashover voltage due to the use of insulated controls is discussed on the basis of utilizing the difference in time lag to protect connected apparatus which may be subjected to increased voltage.