Category: Operations/Technology
Statement: Safe and Economical Electric Operation
Context: Vehicle parts, power supply, track signal
This image illustrates a groundbreaking technological leap forward. In the past, a stoker had to shovel coal while the engineer operated multiple levers to control the locomotive. With the advent of electric train operation, a single button press became sufficient. Using the driving key, the acceleration and direction of the train are set. By pressing the control knob with the left hand, contacts close, supplying power to the motors, and the train starts moving. Since the 1920s, all S-Bahn trains have used this convenient, physically easy-to-operate technology. Some refer to it as the "dead man's switch," but this term more accurately describes the later-added safety driving circuit (SiFa). The SiFa must be regularly pressed and occasionally released with the left thumb, which rests on the control knob. If not, the train will be automatically braked. The right-hand remains on the brake valve.
This system allows for safe train operation with just one person in the driver's cabin. While modern trains still have these features, their appearance has evolved significantly from this model, which is about 50 years old. The SiFa simulator allows operators to practice driving, using the SiFa, and braking techniques.