SNCF Class BB 20005
| Company type | Prototype locomotive |
|---|---|
| Industry | Railway |
| Predecessor | BB16028 |
| Founded | 1961 |
| Fate | Reverted to original form and designation (BB16028) in 1975 |
| Products | Electric locomotive |
The SNCF class BB 20005 locomotive served as a prototype derived from the BB25150 and BB25200 series, reconstructed in 1961 using the damaged BB16028 unit. Once testing concluded in 1975, it was reverted to its original form and designation, BB16028.
History
After the successful evaluation of BB20004, which was the prototype for the BB25500 series, SNCF commissioned a new generation of dual-voltage locomotives: the BB25150 and BB25200 models. These locomotives provided increased power compared to earlier versions, leading to the conversion of a BB16000 into a dual-voltage experimental platform.
Unlike previous prototypes that were fully equipped for AC but had limited DC functionality, BB20005 was outfitted with comprehensive AC and DC systems. This configuration enabled it to achieve nearly 85% of its power output under 1.5 kV DC, a substantial improvement over the 45% capacity demonstrated by BB20004 two years prior.
This prototype played a key role in shaping the bogie designs for both series: the BB25150 bogies were engineered with lower gearing tailored for heavy freight operations, whereas the BB25200 bogies featured higher gearing suited for lighter passenger services and push-pull capabilities.