The topic of the thesis was to create electronic documents of the low voltage installations of railway yards in Oulu district. The documented installations were the lighting of railway yard and gear and gear installations. The thesis work was commissioned by Finnish Transport Agency and the producer was Pöyry CM Oy. The objective of this thesis was to create electronic documents based on available paper documents and on mapping the current state. In addition, the low voltage installations on railway stations were updated. The electronic documents were created using CADS planning program and the documents were saved in DRW- and DWG-format. In addition, the lamp post list was updated accordingly.