Polish railway signalling

The Polish railway signalling (PKP) system provides a complex outlook of traffic situations, yet is quite easy to understand.

Its name reflects the fact that it switches to a red (stop) aspect automatically after a train has passed it but it must be switched back to clear by an explicit action from a signal box or dispatch centre.

A semi-automatic signal can be recognized by its post which is painted with red and white strips.

As presented on this compact chart, semi-automatic signals can display both near and distant functions.

The main difference regards the S1 (red) aspect – After stopping, it can be passed but the subsequent maximum speed is limited to 20 km/h.

A driver who finds himself approaching an unlit signal must stop the train and alert the dispatcher.

Their posts are painted grey and equipped with plates with Roman numerals: III, II, I where the "I" stands closest to the main signal.

Their colour language is identical to warning shields, except the fact they also have a continuously glowing white light, which informs that this is not a main signal but a repeater.

They light up in the front of an approaching train which is the first clue that the system is working correctly.

The colour light signals installed between 1959 and 1969 differ from the contemporary system.

As a matter of fact they can also be used with ETCS, only the LEU unit must be reprogrammed to understand certain combinations of lights differently.

The pictures to the left present old and contemporary configuration with indication which colour chambers may blink if required.