Calcolatrice Sezione Cavo — Formula
## Cable Sizing by Current Density
The cable must carry the required current without exceeding safe temperature limits.
### Simplified Method
**A = I / J**
where A is the conductor cross-sectional area, I is the design current, and J is the allowable current density. Typical values: enclosed cables 3-4 A/mm^2, open-air cables 5-6 A/mm^2. Always verify against manufacturer ampacity tables and installation derating factors.
The cable must carry the required current without exceeding safe temperature limits.
### Simplified Method
**A = I / J**
where A is the conductor cross-sectional area, I is the design current, and J is the allowable current density. Typical values: enclosed cables 3-4 A/mm^2, open-air cables 5-6 A/mm^2. Always verify against manufacturer ampacity tables and installation derating factors.
Esempio Risolto
40 A load with 4 A/mm^2 allowable current density.
- A = 40 / 4 = 10 mm^2
- Select the next standard size: 10 mm^2 or 16 mm^2 depending on available sizes.
- Also verify voltage drop is within limits for the cable run length.