Since multimode fiber has a much larger core than singlemode fiber and glass-clad materials are utilized for its manufacturing process, this kind of fiber shows less bending tolerance. Ideally, the minimum bend radius for multimode fiber should be about 30mm. The fibre optic bending radius fundamentally determines the functionality and lifespan of optical fibre installations – for modern fibre optic cables, a minimum bending radius of 60 mm applies to permanent installations in conduits, while temporary bends during installation allow up to 30 mm. Singlemode fiber has a relatively higher critical bending radius than multimode fiber. During installation under tension, maintain a minimum bend radius of 20 times the cable's outer diameter, while post-installation requires a minimum long-term bend radius of 10 times the cable diameter. All fiber optic cables have specifications that must not be exceeded during installation to prevent irreparable damage to the cable.
