There is no need to calculate ampacity of the cable it would
be provided by the manufacturer its self or else if you want
to calculate it by your self you should also know its
specific resistivity,working temp,core dia & insulation
The current carrying capacity of a cable is called
Ampacity. For the porpose of the above calculation there
are some concepts that must be taken in consideration .
like Dia,Insulation material and thickness,type of conductor
(Copper/Aluminium),Resistivity and the working conditions.
For BETTER CONCEPT I advice the readors to please refer
the "Recommended Cable Sizes and their load capacity as per
IS:13947 & IEC 60947". Below given table can help you.
Rating Cu Al
10A 1.5MM2 1.5MM2
15A 2.5MM2 2.5MM2
20A 2.5MM2 4.0MM2
25A 4MM2 6MM2
Actually current carrying capacity of the cable we can from
the manufacturer, But for the referance purpose I can give
some idea about current capacity of the cable.
So generally we are using two types of cable i.e,. copper &
copper is the best conductor than the aluminium
At 1Sqmm copper conductor will Approx 2 amp in ground
At 1Sqmm copper conductor will Approx 2.4 amp in air
At 1Sqmm Aluminium conductor will Approx 1.2 amp in ground
At 1Sqmm Aluminium conductor will Approx 1.6 amp in air.
for aluminum cable size(air)= load current/1.6
But In the market there is no availability for 72.5 Sqmm so
we can propose 70Sqmm or 95Sqmm.
This is the one of the best procedure for for cable
selection with using catelogues
On the secondary side of a distribution transformer, we use
1c x 630 sq mm cable. Why dont we use 4 core cables instead
of 1 core cables on the secondary. Why we use aluminium
cable glands on the outgoing instead of brass cable glands?