Hello @zorro_66,
the problem with 1-Wire bus is, that there are no guarantees about its functionality. You may have 10 sensors on 100m bus working just fine and you can have 5 sensors on 20m that will not work at all.
The general guidelines are:
Avoid stub and star topology (e.g. use our 4 wire sensors) Use shielded cable and don't lay the cable along the 230V power linesFor more detailed information, try reading this paper from Maxim: https://www.maximintegrated.com/en/app-notes/index.mvp/id/148
Best regards,
Martin