Traduction automatique. Texte original en: EN - afficher l'original The BB 25150 is a class of French dual-voltage electric locomotives designed for mixed traffic and regional services on the SNCF network. Built between 1967 and 1977, these locomotives could operate under both 1'500 V DC and 25 kV 50 Hz AC electrification systems - giving them outstanding flexibility on routes that transitioned between power types. 

Developed as a successor to the earlier BB 25100 class, the BB 25150 series was constructed in three batches, totaling 45 locomotives numbered BB-25151 - BB-25195. They were built by a consortium including Matériel de Traction Électrique (MTE), Francorail and Alsthom. 

Design & technical features:
• Dual-voltage operation: Capable of drawing power from both 1500 V DC and 25 kV AC overhead lines, ideal for mainline and mountainous routes where electrical systems change. 
• Wheel arrangement: Bo’Bo’, reflecting four powered axles on two bogies. 
• Traction & power: Equipped with four TO 136-8 motors with forced ventilation. Under AC the locomotives developed higher power than in DC mode. 
• Top speed: 130 km/h, suitable for passenger services and moderate freight work.

BB 25150 locomotives were deployed across France, especially on lines in eastern and Alpine regions such as Bellegarde - Évian-les-Bains and Aix-les-Bains - Saint-Gervais-les-Bains. They handled both regional trains and mixed traffic duties throughout their career. 

Withdrawals of the class began in 2003 and continued through 2013. A few units were rebuilt into BB 25200 class machines, while others were sold abroad (e.g., to Romanian operators). Two examples - BB 25173 and BB 25188 - have been preserved by heritage groups. / Sources: https://fr.wikipedia.org/wiki/BB_25150