. The street railway review . h potential line be down. The highpotential lines are carried on 40-ft. cedar poles with 7-in. poles are spaced 80 ft. apart on straight tracks and extrapoles are set at all sliarp angles in the line. The style of con-struction as originally built had two cross-arms 4H x 5^ in. in sec-tion spaced 24 in. apart, the top arm being 30 in. below the top ofthe pole. This gave room for two three-phase lines with three in-sulators on either side of the pole and holding the wires at thecorners of an equilateral triangle 30 in. on a side. Glass insulators7 in. in
. The street railway review . h potential line be down. The highpotential lines are carried on 40-ft. cedar poles with 7-in. poles are spaced 80 ft. apart on straight tracks and extrapoles are set at all sliarp angles in the line. The style of con-struction as originally built had two cross-arms 4H x 5^ in. in sec-tion spaced 24 in. apart, the top arm being 30 in. below the top ofthe pole. This gave room for two three-phase lines with three in-sulators on either side of the pole and holding the wires at thecorners of an equilateral triangle 30 in. on a side. Glass insulators7 in. in diameter and 4J4 in. high were use(l in the original construc-tion. These were mounted on a combination wrought iron andwooden pin which held the wire 9 in. above the cross-arms. During the first months of operation many breakdowns occurredthroughout the entire high tension system, due principally to thepuncturing and breaking of the glasses. The display on theseoccurrences especially at night was at times startling and many. TS.\CK , WHEATUN YARDS. that when the armature, in event of failure in the alternating cur-rent supply, exceeds a set speed, the direct current supply is cutoff from the rotary and running away prevented. A blank is used for recording the daily performance of the sub-station machinery. The original size of these sheets, which areperforated for loose leaf binding, is SYz x 14 in. Each sheet is acomplete record for the operation of a single sub-station during aperiod of 24 hours, and as a similar record is used for the generat-ing machinery, any error in the recording instruments or their read-ing can be readily noticed and adjusted while yet fresh in the mem-ory. The daily consultation of these records also furnishes assur-ance against continued hea\T undiscovered feeder or third-railleakage. Distribution System. The three-phase 26,400-volt wires which distribute current tothese six sub-stations were furnished by the Pittsburg ReductionCo. They leav
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Keywords: ., book, bookcentury1800, bookdecade1890, booksubjectstreetrailroads
