Electricity for everyone!

100 years ago, Dr. Bern­hard Jansen filed a patent for the high-speed resis­tor-type tap-chang­er. This inven­tion made it pos­si­ble for the first time to switch trans­form­ers under load, there­by enabling wide­spread elec­tric­i­ty sup­ply.


The inventor

Who was the bril­liant mind behind this rev­o­lu­tion­ary idea? Dr. Bern­hard Jansen, born on 31 August 1899, in Wis­sen an der Sieg, began study­ing mechan­i­cal and elec­tri­cal engi­neer­ing at the Tech­ni­cal Uni­ver­si­ty of Han­nover in 1919, and began his career at the Han­nover Pow­er Plant. In 1928, Jansen became a mem­ber of the board of Oberp­falzw­erke in Regens­burg, which he trans­formed into a mod­ern ener­gy sup­pli­er. To mark the anniver­sary, we’re using arti­fi­cial intel­li­gence to have the bril­liant inven­tor talk about his inven­tion in a pod­cast.

Listen to the podcast with Dr. Bernhard Jansen here.

The patent story

On 13 July 1926 – at the age of just 27 – Dr. Bern­hard Jansen sub­mit­ted his idea to the Reich Patent Office in Berlin. The inven­tion of the so-called high-speed resis­tor-type tap-chang­er solved a prob­lem that was trou­bling many ener­gy sup­pli­ers at the time: reg­u­lat­ing trans­form­ers under load to keep the volt­age sta­ble. It was only through this idea that it became pos­si­ble to cre­ate pow­er grids as we know them today. The basic prin­ci­ple of the inven­tion remains the same to this day. In total, Dr. Jansen held 49 Ger­man patents deal­ing with improve­ments and fur­ther devel­op­ments relat­ed to the tap chang­er.

Learn more about the story behind this ingenious invention.

Made by Reinhausen

When Dr. Bern­hard Jansen set out to build the first pro­to­type of his inven­tion in 1929, he faced a prob­lem: he couldn’t find a work­shop that could man­u­fac­ture a cru­cial com­po­nent – a spe­cial gear for the trans­mis­sion. After a long search, Jansen found a work­shop in the Rein­hausen dis­trict of Regens­burg that man­u­fac­tured the com­po­nent for him in just one day. The name of the com­pa­ny: Maschi­nen­fab­rik Rein­hausen. The begin­ning of a suc­cess sto­ry! Today, the small work­shop has grown into a glob­al­ly active fam­i­ly-owned com­pa­ny that has con­tin­u­ous­ly refined this inge­nious inven­tion over the years and is lead­ing it into the future under the “Made by Rein­hausen” label.

More history


… and sto­ries that bring the anniver­sary to life and offer inspir­ing ideas that bring the anniver­sary to life and offer inspir­ing ideas for the ener­gy sup­ply of the future can be found on Reinhausen’s anniver­sary for the ener­gy sup­ply of the future can be found on Reinhausen’s anniver­sary web­site.


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