Wiring diagrams of electrical apparatus and installations (1913)
McGraw-Hill · New York, McGraw-Hill Book Company · leaf 254
lamps^^^ ^arr^psand res a?7d res. Fig. 401.—Connections for a manually operated block signal. When entering the block,the conductor throws the switch, lighting lamps at both ends of the block; and when leaving,he extinguishes them. The diagram shows the equipment for one block. Where two blocksmeet… … Fig. 402.
Electric wiring
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