Simple Feeding System

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The Simple Feeding System has the most basic OCS configuration, consisting of overhead contact lines and rails.


The Simple Feeding System is economical and ease to maintenance on account of its simple circuit configuration, but in order for a return current to flow to the rail across all sections, there is a large inductive interference in telecommunication lines and a high rail potential which are caused by a leakage current to earth.

The Simple Feeding System has therefore been adopted for rolling stock depots, etc.

This is because the amount of leakage current flowing to earth is small due to short feeding distance.
There is also a system in which a Negative Feeder (NF), which is called "Return Conductor (RC)" globally, is installed parallel to the tracks and is connected to the rail every few kilometers.


The NF (RC) fulfils the role of a protective wire and has a slight shielding effect on telecommunication lines.

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