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9V used to be a voltage standard for electrical components (e.g. motors, lights) in many LEGO sets. The power came from a battery box with one 9V battery (e.g. Town, Space) or later with 6x 1.5V batteries (TECHNIC, Basic). Only the 9V Trains are powered by a DC Transformer and special metal conducting rails for 9V Trains (without any add-on centre conductor rails that were used by the earlier 12V Trains system).

The so called 9V-Powersystem was used in different Town and Space sets between 1985 and 1994 for both Light & Sound and Monorail.

The 9V Trains era was from 1991 to 2007.

In Basic sets and TECHNIC sets the usage of 9V electric components (e.g. motors, lights) during the 1990s was various.

9V powered Themes[edit]

9V powered Sets[edit]






Service Packs

Complete List[edit]