The BAL is an automatic railway signaling system designed to ensure adequate spacing between trains running along the same track
The BAL (automatic luminous block) is the automatic railway signaling system used in France to ensure adequate spacing between trains traveling along the same track. It relies on a system of light signals placed on posts or gantries at the entrance to each block, and on track circuits which change the appearance of the lights according to the progress of the trains.
ERJI/SCLE railway N.S1 products drive and control these light signals. These ‘safety’ lights are designed so that any failure causes the light signals to give restrictive information limiting traffic. They meet EN 50126 and EN 50129 standards.