Source google image: http://www.sbp-prefa.com/wp-content/uploads/2014/06/enveloppe-b%C3%A9ton-ss-cotes-19.jpg
Schema poste de transformation electrique
Source google image: http://www.sbp-prefa.com/wp-content/uploads/2014/06/enveloppe-b%C3%A9ton-ss-cotes-19.jpg