How Calculate Cable Size May 2026

Select a cable where the .

[ V_d = \frac2 \times L \times I \times R_cable1000 ] Where ( R_cable ) = resistance in Ω/km from cable data. how calculate cable size

[ V_d = 7.3 \times 21.7 \times 50 / 1000 = 7.92 \text V ] Still slightly over 6.9 V → try 10 mm² (~4.4 mV/A/m): [ V_d = 4.4 \times 21.7 \times 50 / 1000 = 4.77 \text V \ \text(OK) ] Step 4 – Consider Short-Circuit Temperature Rise For critical installations, ensure the cable can withstand a short circuit until protection operates: Select a cable where the

( 0.03 \times 230 = 6.9 \text V )