Foil winding for high tension transformer - has doubled insulating layer wider and thicker than the metal foil

摘要

The isolating layer in a transformer the windings of which are of metal and esp. of aluminium foil, consists of two layers, and these are for pref. 2-3 mm wider than the metal foil. The two isolating layers are of capacitor paper and for pref. of sodium cellulose paper. Altogether the isolation layer is twice the thickness of the metal foil. The arrangement increases the advantages of this type of winding which is used in the prodn. of high tensions for the removal of dust, etc., and it effectively prevents short circuits between the individual windings, whilst the two layers together reduce the possibility of the occurrence of through holes.