( I = \frac{10,000}{\sqrt{3} \times 415 \times 0.85} \approx 16.4 \text{ Amps} )
You look at your cable table. 29A means you need a (approx AWG 10) copper cable for the thermal rating. cable rating calculation
Choosing the right cable isn't about guessing "thick enough." It’s about : the maximum current a cable can carry before the insulation fails. Get it wrong, and you risk voltage drops, equipment failure, or electrical fires. ( I = \frac{10,000}{\sqrt{3} \times 415 \times 0
Always add a safety margin. For continuous loads (running >3 hours), multiply the load current by 1.25 (125%). Step 2: The "Big Three" Correction Factors Cable tables (like NEC Table 310.16 or IEC 60364-5-52) assume perfect conditions: 30°C air, free airflow, and pure copper. Your site isn't perfect. You must derate. Get it wrong, and you risk voltage drops,
( VD = \sqrt{3} \times 150 \times 16.4 \times 0.0045 ) ( VD = 19.2 \text{ Volts} )
We must upsize.
( VD = \sqrt{3} \times 150 \times 16.4 \times 0.0030 = 12.8V ) ( \text{Percentage} = 3.08% ) (Acceptable).