Answer / 7anoter4

The losses of an insulated conductor in a cable –see, for
instance IEC 60287-1-1- or Neher and McGrath-are losses in
conductor, losses in insulation-dielectric losses-losses in
shield –eddy current and circulating current losses-losses
in armor, losses in metallic conduit.
Losses in conductor w=I^2*R in d.c. R=ro*length/cross
section ro is the resistivity at loaded conductor
temperature T.
ro(T)=ro(20dgr.C)*(1+a*(T-20)) a=temperature coefficient
of resistance.
Or ro(T)= ro(20dgr.C)*(T+K)/(K+20) for copper conductor
K=234.5 for instance.
In a.c. you have to add two other factors: skin effect and
proximity effect.

Answer / 7anoter4

ro(T)= ro(20dgr.C)*(T+K)/(20+K) T=conductor final
temperature in dgr.C

Answer / k.prakashchandra

I^2R

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