Source google image: http://wiki.mchobby.be/images/thumb/c/c4/Relais_250V_%28schema%29.jpg/450px-Relais_250V_%28schema%29.jpg
Schema electrique d un relais
Source google image: http://wiki.mchobby.be/images/thumb/c/c4/Relais_250V_%28schema%29.jpg/450px-Relais_250V_%28schema%29.jpg