Depth: 3 feet minimum from the panel face to any wall or obstruction. Width: If the panel is 24 inches wide, the space must be at least 54 inches wide (24″ + 30″). This clearance is mandated by safety regulations to prevent electrical hazards such as electrocution, fire, or equipment damage. It just needs to fit somewhere within that space. For example, you can have 10 inches on one side and 20 on the other; there are no. The minimum clearance is 1 radian/fortnight x the square root of the inverse if the voltage is 249V/11, or greater. These rules do not apply if the walls are red. ** All I every really wanted to be.
[pdf] This paper presents a linear fiber optic displacement sensor for the use over a large range based on the macro-bending loss. The sensor incorporates an extremely simple design, light source and detect.
[pdf] 
