Seven models are recommended: E32-T11 Fiber Unit, E32-T21, E32-T22B, E32-D11, E32-D21, E32-D21B, and E32-D22B. (These have a bending radius of R4.)
Explanation:
The allowable bending radius of most Fiber Units is 25 mm minimum. Only the seven models listed above have an allowable bending radius of 4 mm. The fiber flexing characteristics have a strong relationship with the bare fiber diameter (see note 1). A bending radius that is 3 times or less the diameter exerts excessive force on the fiber and reduces the optical characteristics (see note 2 on light intensity).
| Model | Bare fiber diameter | Flexing resistance data (light intensity retention, see note 3) |
| E32-T11 E32-D11 |
16 x 0.265 dia. | Value after flexing 1,000 times at a bending radius of 4 mm (with no change)/Value after flexing 1,000,000 times (approx. 80%) |
| E32-T21 E32-T22B E32-D21 E32-D21B E32-D22B |
4 x 0.25 dia. | Value after flexing 1,000 times at a bending radius of 4 mm (with no change)/Value after flexing 1,000,000 times (approx. 85%) |
| E32-TC200 E32-DC200 |
1 x 1 dia. | Value after flexing 1,000 times at a bending radius of 5 mm (approx. 95%) |
Note:
1. Flexible Fiber Units (E32-[][]R) have an allowable bending radius of 1 mm, but do not handle repetitive bending well, so they should not be mounted on movable parts.
2. The light intensity of a Through-beam model is reduced to 50%, which reduces the sensing distance by about 30%.
3.
The Fiber Units listed above have a structure that strongly withstands the bending radius R by using fibers with ultra-small diameters.
Note: Flexible Fiber Units (E32-[][]R) have an allowable bending radius of 1 mm, but do not handle repetitive bending well, so they should not be mounted on movable parts.