Abstract: A position measuring system that includes a graduation support having a first detent and a detector arrangement on a holder for scanning the graduation support at a preset scanning distance. An adjusting device that sets the preset scanning distance, the adjusting device is displaceable relative to the holder along a first direction from a mounting position to an operating position. The adjusting device includes a second detent which, in the mounting position, acts together with the first detent of said graduation support acting in the first direction, and the first and second detents are out of engagement at the operating position and a receiver which, at the mounting position, maintains the graduation support oriented perpendicularly with respect to the first direction, and the receiver is removed from the graduation support by being displaced in the first direction.