Creates elevation planes in the coordinate system with which it is associated. Generally, you create elevation planes after you have created the coordinate system but before you have modeled anything.
Grid planes are used to define the location of grid lines in the model. Assigned to individual coordinate systems, there are two types of grid planes: elevation planes and grid planes.
Elevation planes define the elevation, or height, of the grid line with respect to the origin of the coordinate system and are used in both rectangular and radial grid systems. Elevation planes are always parallel to the X-Y plane of the coordinate system.
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