There are not enough slots available on panel: [Panel Name] for a circuit to be added. Please increase the maximum number of single pole breakers to be greater than [Number] or set it to 0. 
   Namespace:   Autodesk.Revit.DB  
  Assembly:   RevitAPI  (in RevitAPI.dll) Version: 2015.0.0.0 (2015.0.0.0) 
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