SNCF Class BB 12000 SNCF Class BB 12000 The SNCF Class BB 12000 were electric locomotives operated by SNCF. The first examples arrived on the railway in 1953, operating on the 25 kV 50 Hz line to the coal mines of the "Houillères de Lorraine" in the north-east of France. BB 12001 arrived in Mohon on July 17, 1954. Tried first along the Valenciennes – Lumes line, specifications called for a locomotive capable of pulling 750 tonne trains along a grade of 10 ‰. The 12000 Class proved more than capable, pulling 1100 tonne then 1400 tonne trains. BB 12006 using a different system
SNCF Class BB 15000 with the BB7200 and BB22200 series and have even a great deal in common with cabs of other SNCF locomotives of the 1960s. This class was also the first to introduce the VI ("Vitesse Imposée") cruise control system which is now standard on all SNCF locomotives delivered after 1971. The electrical part consists of a single pantograph (type AM18U) which collects 25 kV from the catenary. Power is passed through a transformer which lowers the tension to about 1500 V AC and a bridge rectifier controlled by thyristors rectify it into DC, which is then fed into the traction motors.