Which sequence correctly describes the order of traction power flow from grid to train?

Which sequence correctly describes the order of traction power flow from grid to train?

• A. Substations → power grid → feeders → contact system
• B. Overhead contact system → substations → 1500 V feeders → power grid
• C. Power grid → substations → 1500 V feeders → overhead contact system
• D. Feeders → contact system → substations → power grid

Answer: (C)

The main idea is how traction power travels from the source to the train: it starts at the power grid, goes through substations that convert and regulate the power for rail use, then moves via feeders that carry the 1500 V DC to the railway sections, and finally reaches the overhead contact system where the train’s pantograph draws power. The overhead line is the delivery path to the train, so it comes last in the sequence. The other orders would place the delivery system ahead of the conversion or reverse the flow, which doesn’t reflect how the rail power network actually operates.

The main idea is how traction power travels from the source to the train: it starts at the power grid, goes through substations that convert and regulate the power for rail use, then moves via feeders that carry the 1500 V DC to the railway sections, and finally reaches the overhead contact system where the train’s pantograph draws power. The overhead line is the delivery path to the train, so it comes last in the sequence. The other orders would place the delivery system ahead of the conversion or reverse the flow, which doesn’t reflect how the rail power network actually operates.