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12V was a voltage standard for LEGO Trains sets from 1969 until 1993. In contrast to the older battery powered 4.5V standard, the power of the 12V system came from a mains powered DC Transformer delivered by add-on center conductor rails.

In order to reach the newer 12V standard, the older – but still co-existing – 4.5V Trains system could be upgraded by using different 12V Trains accessories.

Beside the train electricity itself, the 12V Trains system was able to power and control many extendable components, such as automated track accessories or lights.

No futher 12V sets were released after 1986, and the 12V powered trains were replaced by 9V trains in 1993.

Leaflet explaining the transition from 12V to 9V made in 1993 (in French)


Trains Accessories[edit]

link title

Service Packs[edit]

Complete List[edit]

Image # Set Pieces Figures Price Released
No image 11  Locomotive Traction Tyres          
No image 1104  Battery Cables          
No image 1111  Rubber Rims for Locomotive Wheels          
No image 1112  Train Sliding Wheel Blocks          
No image 1119  Locomotive Piston Assemblies          
No image 1138  Replacement Rubber Wheel Treads for Trains          
No image 1140  12V Light Brick          
No image 1146  4 Pushrods, 2 Cylinder Housings          
No image 1147  2 Light Prisms, Light Prism Holder, 2 Red and 2 Yellow Light Covers          
No image 1150  Replacement Motor 12V          
No image 12  Wheel Bearings for Locomotives          
No image 1239  Remote Control for Electric Points          
No image 19  Locomotive Piston Assemblies          
No image 26  12V Motor          
No image 5069  2 Lighting Bricks 12 V          
No image 5083  Remote Control for Crossing 12V          
No image 5084  Lighting Bricks 12V for Signals          
No image 703  12V Replacement Motor          
No image 704  12V Sleeper (Track) Contacts          
No image 705  Motor Bushings          
No image 706  Rail Contact Wires          
No image 708  2m Extension Cord for Points          
No image 722  12V Electric Train with 2 Wagons          
No image 723  Diesel Locomotive          
No image 724  12V Diesel Locomotive with Crane Wagon and Tipper Wagon          
No image 725  Freight Train Set          
No image 726  Western Train          
No image 727  Locomotive          
No image 741  12V Transformer          
No image 742  12V Transformer - for 100V Mains          
No image 750  Straight Conductor Rails          
No image 751  Curved Conductor Rails          
No image 753  Automatic Right Electric Switch          
No image 754  Automatic Left Electric Switch          
No image 755  Left and Right Points          
No image 756  Electric Crossing          
No image 7715  Push-Along Passenger Steam Train          
No image 7725  Electric Passenger Train Set          
No image 7727  Freight Steam Train Set          
No image 7730  Electric Goods Train Set          
No image 7735  Freight Train Set          
No image 7740  Inter-City Passenger Train Set          
No image 7745  12 Volt High Speed Train          
No image 7750  Steam Engine with Tender          
No image 7755  Diesel Heavy Shunting Locomotive          
No image 7760  Diesel Shunter Locomotive          
No image 7823  Container Crane Depot          
No image 7834  Level Crossing          
No image 7839  Car Transport Depot          
No image 7850  Straight Rails          
No image 7851  Curved Rails          
No image 7854  Straight Electric Rails          
No image 7855  Curved Electric Rails          
No image 7856  Electric Points          
No image 7857  Electric Crossing          
No image 7858  Remote Controlled Points Right 12V          
No image 7859  Remote Controlled Points Left 12V          
No image 7860  Remote Controlled Signal          
No image 7861  Lighting Set Electric 12V          
No image 7862  Remote Controlled Decoupling          
No image 7863  Remote Controlled Point Motor 12V          
No image 7864  Transformer / Speed Controller 12V          
No image 7865  Motor Replacement Unit for Battery or Motor-Less Trains 12V          
No image 7866  Remote Controlled Road Crossing 12V          
No image 7867  4 Lighting Standards Electric 12V