Some of the settings available on the Manage tab under MEP Settings - Electrical Settings are also available through the Revit API.
Electrical Settings
The ElectricalSetting class provides access to different electrical settings, such as fitting angles, wire types, and voltage types. There is one ElectricalSetting object per document and it is accessible through the static method ElectricalSetting.GetElectricalSettings().
Fitting angle usage settings for cable trays and conduits are available from the following property and methods of the ElectricalSetting class:
Fitting Angles
Properties of the ElectricalSetting class provide access to:
Methods also are available to add or remove from the project distribution system types, voltate types, wire material types and wire types.