UL 13-2011 pdf download

UL 13-2011 pdf download.Power-Limited Circuit Cables.
a) The 0.003-in or 0.08 mm thickness-reduction allowance mentioned in UL 2556 is applicable to both average and minimum at any point measurements, and is to be applied only to
insulation that is from a stranded conductor as mentioned above and has an average thickness (including any skin) of at least 0.015 in or 0.38 mm where the measurements are made using a micrometer microscope.
b) Only an optical method as applicable from 7.3.2 is to be used for thickness measurements of insulation that is from a stranded conductor as mentioned above and has an average
thickness (including any skin) less than 0.015 in or 0,38 mm.
7.3.1 rv,sed December 7, 2009
7.3.2 Thickness measurements of a nylon or similar covering (see note b to Table 7.3, Table 7.4, and Table 75) of insulation having an average thickness or minimum thickness at any point of not more than 0.0060 In 0(0.152mm (including any skin) are to be made by means of a micrometer microscope or other optical instrument that is calibrated to read directly to at least 0.0001 in (0.1 mu) or 0.001 mm. Each of these measurements is to be recorded to the nearest 0.0001 in or 0.001 mm. Otherwise, under 7.3.1 (b), a simply manipulated optical device that Is accurate to 0.001 In (1 mil) or 0.01 mm may be used for insulation, wTth each measurement recorded to the nearest 0.001 in or 0.01 mm.
7.33 For 7.3.1 (b), the conductor and any covering over the Insulation or skin are to be removed from the finished insulated conductor, wire, or member. A thin slice of the insulation plus any skin is then to be cut perpendicular to the longitudinal axis of the resulting hollow tube. Measurements are to be taken of the maximum and minimum wall thicknesses of the slice. The recorded maximum and minimum thicknesses are to be added together and divided by 2 w’thout any rounding off of the sum but with the resulting average rounded oft (see Sections 73.4 — 7.3.7) to the same degree as stated in 7.3.2 for the recorded measurements. The average thickness so determined and the recorded minimum thickness are to be taken as the average and minimum-al-any-point thicknesses that are to be compared with Table 7.3 or with whatever lesser thicknesses are established for the construction as the result of the insulation-crushing test described in Crushing Resistance Test of Insulation. Section 31.
7.3.4 Rounding off to the nearest 0.0001 in:
A figure in the fourth decimal place is to remain unchanged If the figure In the fifth decimal
place is 0 — 4 and the figure in the fourth decimal place is odd or even, or if the figure in the fifth decimal place is 5 and the figure in the fourth decimal place is even (0, 2, 4. and so forth). A figure in the fourth decimal place is to be increased by 1 if the figure in the fifth decimal place is 6 — 9 and the figure in the fourth decimal place is odd or even, or it the figure in the fifth decimal place is 5 and the figure in the fourth decimal place is odd (1, 3, 5, arid so forth).
7.35 Rounding off to the nearest 0.001 in:
A figure in the third decimal place is to remain unchanged if the figure In the fourth decimal place is 0 — 4 and the figure in the third decimal place is odd or even, or if the figure in the
fourth decimal place is 5 and the figure In the third decimal place is even (0, 2, 4. and so forth). A figure in the third decimal place i to be increased by 1 if the figure in the fourth decimal place is 6 — 9 and the figure in the third decimal place is odd or even, or if the figure in the fourth decimal place is S and the figure in the third decimal place is odd (1. 3. 5. and so forth).