Different installations for flush, non flush, quasi flush sensors
Flush Mounting:
Can be installed with their sensing faces flush to the metal. The distance from opposing metal surfaces must be≥ 3sn and the distance between two proximity switches (side-by-side) ≥ 2d.
Non flush Mounting:
They have no metal housing surrounding the area of the sensing face. The sensing face must extend ≥ 2sn from the metallic installation medium. The distance from opposing metal surfaces must be ≥ 3sn and the distance between two adjacent proximity.
Quasi-flush Mounting:
Require a space behind the sensing face which is free of conducting materials.
Under this condition the specified switching distance is available without limitation.