by Dennis Collin
I have been often asked how to model such elements such as heavy-duty cables either as supports or for electrical infrastructure. Revit’s MEP tools do have wires, but they are 2D, view specific elements and therefore do not show in 3D views.
Fig 1. MEP’s wires are 2D objects only!
If cables need to be viewed in 3D or section or elevation views, one approach is to utilise Adaptive components.
Adaptive components can be stretched off their current work planes and can be used to model distorted geometry such as twisted or warped panels on building facades.
To make a component such as a cable element, create a family from the Generic Model Adaptive Template.
This will then display the adaptive family environment.
Fig 2. Creating a series of adaptive points that will form our cable.
For our cable example, add several points (in this example will use 5 points), which can then be set to adaptive. Adaptive points will be used to define where the length of cable will be located.
Fig 3. Draw a circle entity on a point by using the point’s work plane.
Select the points and create a reference spline entity. This will form the centreline of the cable. By choosing reference spline type will be the line will be retained after any geometry is formed.
Fig 4. Creating solid geometry for the cable.
Select the circle and the spline path and create a solid ‘swept’ form. Once complete the screen should look like the element below.
Fig 5. Adaptive Component ready to place and test!
The adaptive points which were used to form the geometry are numbered sequentially and will be used to place this snake-like element within a project. These points can be selected later and moved in all 3 axes (X,Y and Z).
Regular families can be created to represent cable supports where a cable needs to cross over a walkway or road as per the image below. Although no category exists for electrical cables a suitable subcategory can be created if required.
Fig 6. Cables and supports shown in a sample infrastructure model.
There are a few limitations with this approach, regarding schedules. Although elements can be counted and tagged, the regular interface does not expose the adaptive components length. Although this may be accessible via the API (programming interface or Dynamo scripting).
I will discuss workarounds to this limitation in a future post.