Engines and winding wheels of the San Francisco cable car system
Cable Cars have no engine or motor on the cars themselves. The power source is centralized in the cable car barn and powerhouse at Washington and Mason Streets (also home to the Cable Car Museum). There, powerful electric motors (originally a stationary steam-powered engine) drive giant winding wheels that pull cables through a trench beneath the street, centered under the cable car tracks (that’s what’s in that slot between the tracks).
There are actually four cables, one for the California line, one for Powell Street, and one each for the outer ends of the two Powell lines (Mason and Hyde). Each cable has its own set of winding wheels. The rearmost winding wheel in each set is adjustable. When a cable is new, this rearmost wheel is close to the other winding wheels. As the cable naturally stretches out with use, the wheel is gradually moved back by shop workers to keep constant tension on the cable. The cables are over an inch in diameter, with six steel strands of 19 wires each wrapped around a core of sisal rope.
Engines and winding wheels of the San Francisco cable car system
Cable Cars have no engine or motor on the cars themselves. The power source is centralized in the cable car barn and powerhouse at Washington and Mason Streets (also home to the Cable Car Museum). There, powerful electric motors (originally a stationary steam-powered engine) drive giant winding wheels that pull cables through a trench beneath the street, centered under the cable car tracks (that’s what’s in that slot between the tracks).
There are actually four cables, one for the California line, one for Powell Street, and one each for the outer ends of the two Powell lines (Mason and Hyde). Each cable has its own set of winding wheels. The rearmost winding wheel in each set is adjustable. When a cable is new, this rearmost wheel is close to the other winding wheels. As the cable naturally stretches out with use, the wheel is gradually moved back by shop workers to keep constant tension on the cable. The cables are over an inch in diameter, with six steel strands of 19 wires each wrapped around a core of sisal rope.