• Revit

Define electrical distribution systems

Add and connect electrical distribution elements for a conceptual distribution system for electrical analysis.

Tutorial resources

These downloadable resources will be used to complete this tutorial:


Step-by-step guide

Revit provides electrical engineering load estimating workflows that allow for decision making to be done early on in the design process. Capturing the area-based loads and other electrical requirements natively within Revit allows users to determine what the preliminary building load will be.

In this example, an area-based load named LTG has already been applied to the plan for the lighting. Now, define a conceptual analytical distribution system and electrical elements for it.

First, add an electrical analytical power source, such as a utility or a generator:

  1. In the System Browser toolbar, click Add Electrical Analytical Power Source.
    In the System Browser toolbar, Add Electrical Analytical Power Source highlighted in red.
  1. In the Power Distribution hierarchy, rename the power source to match the project needs. In this example, “Utility Power” is entered.
  2. With the power source still selected, click Add Electrical Analytical Bus.
    In the System Browser, Utility Power highlighted in red, and in the toolbar, Add Electrical Analytical Bus highlighted in red.

These may be used to represent any type of bus in concept, such as a panel, switchboard, busway, or motor control center.

  1. Rename the bus—in this case, to “Main SwitchGear”.
    In the System Browser, the newly added bus renamed to Main SwitchGear and highlighted in red.
  1. Click Add Electrical Analytical Transformer.
    In the System Browser toolbar, Add Electrical Analytical Transformer highlighted in red.
  1. Continue adding electrical analytical distribution elements, such as a Building Electrical Panel in this example, until the basic infrastructure for the building is complete.

Keep in mind that, except for power sources, when a new electrical element is created, it will be supplied by the currently selected element.

For specific loads, define an equipment load:

  1. In the System Browser, with one of the elements selected, click Add Equipment Load.
    In the System Browser, a newly added element named Building Electrical Panel highlighted in red, and in the toolbar, Add Equipment Load selected.
  1. Rename the equipment load, in this example, to “Shop Eqpt”.
  2. Continue adding equipment loads until the specific loads are complete.
    In the System Browser, newly added equipment loads appear in the hierarchy under the element.

Once the hierarchy of elements is created, ensure that they are being supplied with power. In this example, the LTG area-based load is still unconnected.

To adjust the power supply:

  1. Select the element—in this case, the LTG area-based load.
  2. In the Properties palette, under Electrical – Circuiting, expand the Supply From drop-down to view the available power supply options.
    In the System Browser, the area-based load selected and highlighted in red, and in the Properties palette, the Supply From drop-down expanded.

Note that this same drop-down is also available from the Modify | Electrical Analytical Loads contextual tab.

  1. For this example, select the Building Electrical Panel to power the lighting.
    In the System Browser, LTG selected and highlighted in red, and in the ribbon, Analytical Load Tools panel, the Supply From drop-down set to Building Electrical Panel, highlighted in red.

The System Browser hierarchy updates.

Further define these electrical elements from the System Browser:

  1. Select an element such as an Equipment Load.
  2. In the Properties palette, specify the Load Classification, Voltage, Power Factor, or Apparent Load.
  3. In this example, to define the Apparent Load, under Electrical – Loads, select the Apparent Load text field and enter a value, such as 80,000.
    In the System Browser, an equipment load selected and highlighted in red, and in the Properties palette, an Apparent Load of 80,000 set and highlighted in red.
  1. Continue modifying the electrical elements as needed.

As the elements are defined, the System Browser updates accordingly, which keeps all analytical electrical system elements directly within the Revit environment. This makes it much easier to determine preliminary building load and load on main equipment components directly within the model.