I was recently exposed to an issue with electrical panel loads that illustrated what I feel are unique characteristics of how Revit circuit loads and Load Classifications affect the values that you see on the electrical panel schedule. If everything is utilized in Revit exactly as Revit is designed and intended, everything works fine. However, that rarely happens. Engineering firms create and customize families, and change or set Load Classifications which can impact the proper loading calculations.
Many companies have electrical panel schedules which display the Loads Summary at the bottom of the panel. This summary section separates each Load Classification into its own line so that you can see how much Connected Load exists for each different type of Load Classification and the Estimated Demand for each Load Classification. Those load values are then displayed as the Total Connected Load and the Total Demand Load that should include everything on the panel. The Total Connected Load is then displayed on a Switchboard panel schedule from which that panel is served. There are many different variations of how this information is displayed, but the general process is the same. Subpanels may also be involved, but the same issues exist with those loads.
In reviewing the issue, there were 2 different problems that were manifested in the panel loading. This article is an attempt to describe those 2 problems to help others understand what may be happening when load numbers don’t add up. I recommend everyone read the Autodesk Knowledge Network’s explanation of how Load Calculations are supposed to work. Read it at About Load Calculations.