Translations:How to operate relay line block equipment/27/en

If all these requirements are met, the main signal can be set to clear in the direction of the neighbouring signal box. As soon as the main signal shows "clear", the line repetition interlock becomes effective (Polish: przekaźnika przeciwwtórności liniowej). It prevents two trains in a row from entering the same block section without having the line bock being properly operated in the meantime.