Cable Size Calculation

No! Do your own homework.

Go here

http://www.constructionmonkey.com/calculations/electrical/Default.aspx

...or go to British Standard 7671.

Next!

There have been countless posts on CR4 about "cable size calculation". As a practical matter, cable sizes are not normally calculated; instead, they are looked up in tables from electrical Codes and cable manufacturers. Of course, somebody sometime had to calculate the numbers that are given in such tables, but the calculations are too complex for easy day-to-day use. That is why the tables have been calculated beforehand, enabling users simply to look things up. Most local/regional/national Codes have this information. Please purchase a copy of your local Code, and go from there.

Pl. attend to our training programme on EDSA-A (Electrical Design of Switchgear Assembly-Advanced) wherein we also teach cable selection.

1. 6.6kv, 510Kw , 50hz, Compressor Cable length 120M / underground?

Ans). Cable Size is 3.5C x 120Sq.mm XLPE Aluminium Armoured Cable, Full load Current is 124.34A after considering derating factor and voltage drop is 1.89% for this cable.

2. 110kW Blower, 415V, 3 phase, 50hz, Cable length 120M / underground?

Ans). Cable Size is 3C x 16Sq.mm XLPE Aluminium Armoured Cable, Full load Current is 28.99A after considering derating factor and voltage drop is 2.85% for this cable.