Calculate Cable Size [upd] Link

A 2000W water heater on 230V. ( I = 2000 / 230 = 8.7 \text Amps ) Step 2: Determine the Round-Trip Cable Length Many forget this. If your device is 20 meters from the source, the actual electrical path is 40 meters (go and return).

| Condition | Derating Factor | | :--- | :--- | | Ambient 30-40°C (normal) | 1.00 | | Ambient 40-50°C (hot attic) | 0.87 | | 3-6 cables bundled | 0.80 | | 7-9 cables bundled | 0.70 |

You need at least 7.3 mm² . The nearest standard size is 10 mm² (since 6 mm² would be too small). Step 4: Adjust for Temperature and Grouping The formula above assumes ideal conditions. If cables run through hot attics or are bundled together, use these derating factors (from NEC/CEC tables): calculate cable size

[ \textMin. Cross Section (mm²) = \frac2 \times \rho \times I \times LV_d ]

Step 3: Apply the Voltage Drop Formula The basic DC / single-phase AC formula is: A 2000W water heater on 230V

Choosing the wrong cable size isn't just an inconvenience—it’s a fire hazard. Undersized cables overheat, melt insulation, and can cause voltage drops that damage your equipment.

Now calculate cable size for , not 5A. Quick Reference: Common Cable Sizes & Current Ratings (Copper, 30°C) Use this as a starting point only—always verify with local codes. | Condition | Derating Factor | | :---

Got a specific project in mind? Drop the details below, and I’ll help you calculate it! Disclaimer: This guide is for educational purposes. Electrical work can be dangerous and fatal if done incorrectly. Always comply with local codes and regulations, and hire a qualified electrician for permanent installations.