The EN 17168 has finally provided a reference for the electrical design of Platform Screen Doors (or Platform Barrier Systems) for the interface with the station, the rolling stock and the platform, including interaction with passengers. Two main configurations are possible,with PSD potential bonded to the station earth or to the track ( or floating, insulated from both), each with advantages and disadvantages that deserve attention for suitability for construction and maintenance, as well as for a system assurance perspective. The risk assessment and the technical judgment are carried out half formally half recurring to past experience, thus deviating often from a formal system-assurance-oriented approach in favor of clarity and completeness. Issues related to maintenance are discussed considering typical approaches, the most frequent repair and verification operations, and the normal aging of materials and systems. The outcome of the analysis is a preference for the earthed PSD that allows a better control of interfaces and a more durable design.

Platform screen doors; earthing; bonding; electrical safety; stray current; design; maintenance