In the line circuit is the selector switch box, connected to the normally open switch points. A circuit-breaker box is clamped to the up-and-down rod of the home signal, with both sides of the circuit breaking through this box. ... Wiring diagram.
|Title||:||Annual Report[s, and Final Report] of the Black Signal and Train Control Board to the Interstate Commerce Commission|
|Author||:||United States. Block Signal and Train Control Board|