The PE-PL system is designed to ensure the safe management of level crossings, preventing the premature opening of barriers. Opening is only permitted after an Audio Frequency track circuit installed at the crossing has been cleared, in combination with traditional detection via a release pedal.

The electronic processing unit within the sentry box ensures that the barriers are only opened after the train has completely passed. The system provides continuous diagnostics, even in the absence of rail traffic.
Thanks to its ease of installation and compatibility with existing systems, the PE-PL requires no significant modifications to the signalling logic and provides continuous diagnostics even when no trains are present.