Abstract
For the accurate planning of overhead lines, a catenary–based calculation is used, because the conductor curve in the span takes the shape of the catenary. On the other hand, there is a parabola–based calculation, which is considered approximate and is usually applied in the case of overhead line with spans up to 400 metres, since the difference between the catenary and the parabola is then almost negligible. While there are generally no differences in important formulas for parabola–based calculations in different literature, some important formulas differ in the case of the catenary–based calculations. This article deals with the interpretation and evaluation of such different formulas for the same quantities and provides a clear answer regarding the usability of the examined formulas in different literature.