The Return Path Of A Third Rail

Ground, that is the other two rails

Some background reading on the Hong Kong Mass Transit railway would be of interest as to the sort of things that can happen when the return ground/earth path is inadequately bonded. On a DC supply, the return currents were passing through parts of the re-bar in the concrete support structures, causing accelerated corrosion effects in it leading to structural deterioration. Google it!

Isn't it always the "little" details that bite us in the rear?

Just this past weekend, I read an article about outside rail powered trains that had another rail down the middle of the running rails. This was used for return to ground as there was some problem using the running rails. It looked like Lionel track with a fourth rail on the outside.

"third rail has only 1 conductor..what is the return path of it???"

From 3rd rail, 3rd rail pickup shoes, traction motors, train wheels, to the two ground rails.

thank u all...i got my ans......its two other rails....i guesed that but 2 b comfd just asked in cr4

The running rails.

Yes, Ground.