طريقة حساب سمك طبقات القابلو

Page 1

Fictitious Calculation method a. 4x4 mm2 CU/XLPE/SWA/PVC 0.6/1 kV 1. Conductor (4 mm2): Fictitious diameter of conductor dL = 2.3 mm 2. Cores: The fictitious diameter Dc of any core is given by: Dc = dL + 2ti Where ti is the nominal thickness of insulation, ti = 0.7 mm Therefore, Dc = 2.3 + 2*0.7 = 3.7 mm 3. Diameter over laid-up cores The fictitious diameter over laid-up cores (Df) is given by: Df = k Dc Where the assembly coefficient k is 2.42 for a four-cores cable Therefore, Df = 2.42 * 3.7 = 9.0 mm 4. Thickness of extruded inner covering As per table 8.0 of IEC 60502-1, if the fictitious diameter over laid-up cores above - mm up to and including 25 mm, the nominal thickness of extruded inner covering is 1.0 mm. 5. Inner Coverings The fictitious diameter over the inner covering (DB) is given by: DB = Df + 2 tB Where tB = 0.4 mm for fictitious diameter over laid-up cores (Df ) up to and including 40 mm DB = 9.0 + 2 * 0.4 = 9.8 mm 6. Armour The nominal diameters of round armour wires shall be as per table 9.0 of IEC 60502-1. As per table 9.0 of IEC 60502-1, if the fictitious diameter under the armour above - mm up to and including 10 mm, the nominal diameter of round armour wires shall be 0.8 mm.

b. 4x4 mm2 CU/XLPE/LEAD/SWA/PVC 0.6/1 kV Page 1/3


Turn static files into dynamic content formats.

Create a flipbook
Issuu converts static files into: digital portfolios, online yearbooks, online catalogs, digital photo albums and more. Sign up and create your flipbook.