During a campus backbone installation, a contractor pulls a 24-strand outdoor loose-tube cable around a 90-degree conduit bend. The conduit diameter is 2 inches, and the cable diameter is 0.5 inches. The contractor bends the cable over a 4-inch radius. Why is this a problem?
Answers
AThe bend radius is too tight; under tension, the minimum bend radius is typically 20x the cable diameter (10 inches)
BThe conduit is too small for a 0.5-inch cable
COutdoor cable cannot be run in conduit
DThe bend radius must be exactly 15 inches for all cables
Correct answer: A — The bend radius is too tight; under tension, the minimum bend radius is typically 20x the cable diameter (10 inches)
Fiber cables under pulling tension generally require a bend radius of at least 20 times the cable diameter (0.5 * 20 = 10 inches). Bending it at 4 inches risks breaking the glass or inducing macrobends.
MIFOTRA exam practicealigned to TIA-568.3-D / ITU-T G.652·3 marks·Medium