Section 4.7.1 specifies the insulation concentricity requirements for shipboard cables. The insulation on individual conductors shall be uniform in diameter throughout the conductor length. Concentricity at any cross-section shall be not less than 85 percent for specified minimum average wall thickness greater than 0.025 inch, nor less than 75 percent for specified minimum average wall thickness of 0.025 inch or less.
This is a dimensional inspection requirement that ensures the insulation is evenly distributed around the conductor to maintain proper electrical and mechanical performance in naval shipboard applications.
The cable jacket shall also be applied concentrically to the cable core in a manner to maintain circularity in the completed cable, with concentricity not less than 75 percent.