An invertible optical float switch is provided, comprising a floatable housing having an interior, a central longitudinal axis, a top end and a bottom end; first and second optical fibers each having proximal and distal ends, the proximal end of the first optical fiber connectable to a light source located remote from the housing, the proximal end of the second optical fiber connectable to a light detector located remote from the housing, the distal ends of the first and optical fibers positioned in the interior of the housing and the distal ends being mounted in the interior on a separator assembly such that the distal ends are optically aligned and separated by a gap; the separator assembly further including a movable member, the movable member adapted to be movable by gravity between a first position where the movable member occupies the gap such that the distal ends are no longer optically aligned, and a second position where the movable member does not occupy the gap; wherein the distal ends and the separator assembly are mounted on a paddle positioned in the interior of the floatable housing, the paddle adapted to be mounted either in position A with the gap closer to the top end of the floatable housing than the bottom end of the floatable housing, or in an inverted position B with the gap closer to the bottom end of the floatable housing than in position A.