Danish to English Tech/Engineering Transport / Transportation / Shipping Railway signalling

Hovedtogveje fremkommer på grundlag af dværgtogveje for "skifting tilladt" som en overbygning på disse, idet der blandt andet sikres, at særlige hovedtogvejs betingelser er opfyldt med hensyn til fastlægning og tidsopløsning samt sikkerhedsafstande (forløb).

These questions relate to an odd text on train signalling written in the 1960's. It has subsequently been edited several times over a number of years, but where all the additions are in Norwegian.

Proz won't allow me to use the "Trains = Transportation category" when asking this querstion.