I have 30m 16mm2 4-core swa 90C thermosetting run at 70C. I want to establish Z1+Z2 using PD CLC/TR 50480:2011 as set out in the IET design guide and will be using wire armour as cpc. The vector equation is;
(Z1+Z2) =(R1+1.1R2) + (0.3)x milliohms per metre.
Line is 1.51, (x can be ignored), DC resistance of wire armour is 3.1. All at 20C
There is no explanation but I assume that the line is raised to 70C and the wire armour to 60C.
Would some kind soul check my understanding. I make the impedance of line and cpc at design temp to be 0.162 ohms.
This is purely academic.
