. The Bell System technical journal . ently,two types of anti-contacting insulators were developed. One type,Fig. 14, was a perforated disc of insulating material. When this typewas installed on one wire of a pair it was not in contact with the otherwire of the pair except when forced there by the action of the wiresin wind. The other type, Fig. 15, was a rod-shaped insulating spacer bridged the two wires of a pair in the span. The insulating discs used were 3 and 4 inches in diameter. Thearrangements of these discs tested in natural winds comprised one,two or three discs per span
. The Bell System technical journal . ently,two types of anti-contacting insulators were developed. One type,Fig. 14, was a perforated disc of insulating material. When this typewas installed on one wire of a pair it was not in contact with the otherwire of the pair except when forced there by the action of the wiresin wind. The other type, Fig. 15, was a rod-shaped insulating spacer bridged the two wires of a pair in the span. The insulating discs used were 3 and 4 inches in diameter. Thearrangements of these discs tested in natural winds comprised one,two or three discs per span per pair of wires. When one disc wasused, it was placed at the approximate center of the span on the wire 222 BELL SYSTEM TECHNICAL JOURNAL of the pair to the windward side of the Hne. When two discs wereused they were placed on the windward wire at one-third of thedistance from each support. The three-disc arrangement comprisedthe two-disc arrangement with the third disc placed at the center ofthe span on the other wire of the Fig. 15—Insulating spacer. In selecting the disc and these sizes, various shapes and sizes ofinsulators (one of which is shown in Fig. 13) were tested using theaccelerated method of test referred to above. The circular type wasfound to give as good results as any other shape and had the advantageof being simple in design. The insulating spacers were used one per span per pair of wireslocated at the approximate center of the span. Any insulating spacerbridging the wires of a pair constitutes an additional line leakagepath and from this standpoint is undesirable. In this respect thediscs have a distinct advantage over the spacers. As stated above,they are not normally in contact with both wires and when suchcontacts take place they are generally of short duration. Then too,in a long line with wires equipped with discs it is improbable thatmore than a short section would be affected at one time. The thoughtwas that owing to the additional line leak
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Keywords: ., bookcentury1900, bookdecade1920, booksubjecttechnology, bookyear1
