http://www.iec.ch/TC57/CIM#PositionPoint
Class cim:PositionPoint

Class [owl:Class]

Set of spatial coordinates that determine a point, defined in the coordinate system specified in 'Location.CoordinateSystem'. Use a single position point instance to desribe a point-oriented location. Use a sequence of position points to describe a line-oriented object (physical location of non-point oriented objects like cables or lines), or area of an object (like a substation or a geographical zone - in this case, have first and last position point with the same values).

Thing

cim:PositionPoint.zPosition max 1 string

cim:PositionPoint.yPosition max 1 string

cim:PositionPoint.xPosition max 1 string

cim:PositionPoint.sequenceNumber max 1 nonNegativeInteger

cim:PositionPoint.groupNumber max 1 nonNegativeInteger