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.
whenever the DWLAbbreviated term for Driver’s White Light. is not LitThe internal illumination of signalling equipment..