# Copper cable current Gauge calculation

I want to calculate theoretically the current carrying capacity of a cable. I have 24 Awg cable, which is having 8 strands: the overall dimension of the cable is 1.27mm and each strands dia 0.15 mm approximately. What I need is a relation, an equation which enables me to calculate its current carrying capacity.

Since I dont have datasheet, can someone give me an equation for calculating it, or any chart where I could see relationship between strands characteristics and current carried?

• How will you cool the wire? Dec 13 '18 at 15:21

The theoretical calculation of the wire's current carry capability is not that easy. It depends on factors like ambient temperature, the mounting conditions, the convection coefficient, the max allowed temperature of the insulation, the conductor's material and so on.

I recommend using a dimensioning table like this for the first indication.

The cross section of your strands can be easily calculated with $$A_{Strand}=\left(\frac{d}{2}\right)^2\pi=\left(\frac{0.15}{2}\right)^2\pi=0.017mm^2$$

and the total cross section is $$A_{total}=N\cdot A_{Strand}=8\cdot 0.017=0.141mm²$$

The lookup table suggests a maximum current of approx 2.2Amps for this cross section.

• Thanks it helps a lot. I also done same calculation.please let me if wire guaze is 22 . how can consider those value to match current as per chart mentioned. in that dia of conductor mentioned 0.64516 mm. How it be correlated to current
– AMPS
Dec 14 '18 at 8:32