Reference Date Title Language ENV 50234:1997 1997-02-05 Aeronautical ground lighting electrical installation - Flashing lights: Equipment specifications and tests     EN 61821:2003 2003-01-07 Electrical installations for lighting and beaconing of aerodromes - Maintenance of aeronautical ground lighting constant current series circuits     EN 50490:2008 2008-08-14 Electrical installations for lighting and beaconing of aerodromes - Technical requirements for aeronautical ground lighting control and monitoring systems - Units for selective switching and monitoring of individual lamps     EN 61823:2003 2003-06-13 Electrical installations for lighting and beaconing of aerodromes - AGL series transformers     EN 50512:2009 2009-02-13 Electrical installations for lighting and beaconing of aerodromes - Advanced Visual Docking Guidance Systems (A-VDGS)     ENV 50235:1997 1997-02-05 Aeronautical ground lighting electrical installation - Signs: Equipment specifications and tests     ENV 50230:1997 1997-02-05 Aeronautical ground lighting electrical installation - Control and monitoring systems: General requirements     EN 61822:2009 2009-07-15 Electrical installations for lighting and beaconing of aerodromes - Constant current regulators     EN 61821:2011 2011-11-25 Electrical installations for lighting and beaconing of aerodromes - Maintenance of aeronautical ground lighting constant current series circuits