. The Street railway journal . essure. Each petticoat was tested sep-arately, the top section to 45,000 volts. Ineach case these tests lasted four minutes,and following this the assembled insulatorwas subjected to 85,000 volts for ten min-utes, and also a precipitation test was madeat 52,500 volts. The insulators are mount-ed on iron pins. A unique feature of the transmission lineis the method of protection from lightning,which consists of a seven-strand galvan-ized steel cable, 5-16 in. in diameter, strungfor the entire length of the line on top ofthe transmission poles, 4 ft. above theneares
. The Street railway journal . essure. Each petticoat was tested sep-arately, the top section to 45,000 volts. Ineach case these tests lasted four minutes,and following this the assembled insulatorwas subjected to 85,000 volts for ten min-utes, and also a precipitation test was madeat 52,500 volts. The insulators are mount-ed on iron pins. A unique feature of the transmission lineis the method of protection from lightning,which consists of a seven-strand galvan-ized steel cable, 5-16 in. in diameter, strungfor the entire length of the line on top ofthe transmission poles, 4 ft. above thenearest active wire, and provided withground connections at every fifth form of protection from lightning isbelieved to be an efficient supplementaryadjunct to the arresters. In all there are 71 miles of transmission line. This waserected at a speed of from one-half mile to 2 miles a day; thework including the digging of holes and pole erection, besides 11 thelarge of those organizingint of steam trafficame time materially.
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectstreetr, bookyear1884
