Some common sense about bending restrictor
The bending restrictor is a component installed around the umbilical cord or flexible part to prevent excessive bending of the cable and damage. Each umbilical cord or flexible cable has a minimum bending radius, below which the cable may be severely damaged and unusable. The bend limiter consists of a number of interlocking elements that react when subjected to an external load and lock together to form a smooth bend radius.
Choose the radius equal to or greater than the minimum bend radius of the cable to be protected.