Design software for overhead contact line systems


SIGNON OLAcad is based on the construction design program AutoCAD®which uses pre-defined objects. These objects, such as lines, circles and text, have certain properties – such as line width, color and font size, for example – and can be linked to each other.


Using the same approach, SIGNON OLAcad defines new objects particularly related to overhead contact lines, such as masts, contact wires, and clamps, all with specific properties.

OLAcad objects in AutoCAD
SIGNON OLAcad objects in AutoCAD® (click to enlarge)

When different objects are combined, their respective properties interact. These interactions are balanced iteratively. If, for example, the position of a mast is changed, the related forces, geometrical data and other values are recalculated and the representation is adjusted accordingly. This way, it is possible to see the influence of changes on the graphical design result or the static loads.

The overhead contact line system is developed from a number of connected elements and stored in a CAD drawing. This CAD drawing contains all the properties of its “smart” elements, i.e. it contains both the graphical elements for the representation of the design and all the data relating to them.

This procedure is required for top view (2D) and perspective (3D) representations. The drawing provides additional longitudinal sections and cross-sections of the overhead contact line system. This makes it possible to recognize any conflicts early on and to provide an overview of the future layout of the system at an early stage.


In order to use the 3D function of SIGNON OLAcad, the underlying drawings of buildings and engineered structures should also be available as 3D drawings. Should the 3D drawings not be available, the design engineer can insert simplified 3D polygons into the drawing at the corresponding points for further reference.

All the usual AutoCAD® commands are available to the design engineer. They are complemented by menus in which the properties of the objects can be entered or selected from a library and adjusted as needed.

When SIGNON OLAcad is installed, all the properties and functions of the design in the CAD drawing are preserved. Even if SIGNON OLAcad is not used, the designs can be opened with AutoCAD®, superimposed with data from other designers, and exported.

OLAcad menus and tools
SIGNON OLAcad menus and tools (click to enlarge)

Functions at a glance:

  • Re-defined „smart“ overhead contact line elements with interacting properties
  • Automatic recalculation of geometric data and other variables after changes to properties
  • Semi-automated design steps
  • Multiple standards for each axis distortion available


  • Extensive construction phase design possible in a single drawing
  • Static calculation in accordance with EN 50119
  • Numerous output and export possibilities
  • Reloading of revised data tables possible
  • Simple revision of plans after build