- State Place Coordinate System.
A system for specifying local coordinates, covering all of the United States. SPCS divides each US State into one or more zones known as State Plane Zones. Each State Plane Zone can be treated as a Cartesian grid, and allows for coordinates to be converted between local Cartesian grid coordinates and latitude and longitude. This allows for accurate positioning, but coordinates cannot be mixed across Zone boundaries. When traversing zone boundaries latitude and longitude needs to be used instead.
The State Plane Coordinate System is not itself a projection or a single coordinate system. It is a standard specifying for each zone in each US State which projections to use to produce a zone specific coordinate system.
The system was developed in the 1930s by the US Coast and Geodetic Survey, and has been revised several times since then.
Also, sometimes known as "State Plane System" (SPS).
For more information see:
- http://everything.explained.at/State_Plane_Coordinate_System - State Plane Coordinate System Explained.
- http://geology.isu.edu/geostac/Field_Exercise/topomaps/state_plane.htm - State Plane Coordinate System.