A SignalA visual display device which conveys instructions or provides prior warning of instructions regarding the driver’s authority to proceed. that is displayed to a train driver approaching an ABCLAbbreviated term for Automatic Barrier Crossing Locally Monitored. or AOCLAbbreviated term for Automatic Open Crossing Locally Monitored. to
indicate that the Level Crossing protection systemThe operation of Road Traffic Signals and/or Barriers/Gates manually or by an approaching train. has activated.