Source google image: http://3.bp.blogspot.com/-SzHb69O97zM/UdtY3Zrpk0I/AAAAAAAAIJc/s_Nv6MhLQws/s1600/Signalisation+de+s%C3%A9curit%C3%A9.JPG
Schema electrique de feux de signalisation
Source google image: http://3.bp.blogspot.com/-SzHb69O97zM/UdtY3Zrpk0I/AAAAAAAAIJc/s_Nv6MhLQws/s1600/Signalisation+de+s%C3%A9curit%C3%A9.JPG