BS 7671 Electrical Wire Size Calculator for India (Copper, 1–10 sqmm)
This free online calculator helps you select the correct copper wire size (1–10 sqmm) for your electrical installation in India, using the BS 7671 cable sizing method. Enter your load in amps or watts to get the recommended cable size instantly.
How BS 7671 Cable Sizing Works
- Based on the current-carrying capacity of copper cables as per BS 7671 (IET Wiring Regulations).
- Assumes single-phase, 230V, PVC insulation, reference method C (clipped direct), ambient temp 30°C.
- Always consult a qualified electrician and the latest BS 7671 tables for critical installations.
Copper Cable Size Chart (BS 7671, up to 630 sqmm)
| Wire Size (sqmm) |
Max Amps (A) |
Typical Load (W) at 230V |
| 1 | 11 | 2,530 |
| 1.5 | 14.5 | 3,335 |
| 2.5 | 20 | 4,600 |
| 4 | 26 | 5,980 |
| 6 | 32 | 7,360 |
| 10 | 44 | 10,120 |
| 16 | 57 | 13,110 |
| 25 | 76 | 17,480 |
| 35 | 96 | 22,080 |
| 50 | 116 | 26,680 |
| 70 | 146 | 33,580 |
| 95 | 176 | 40,480 |
| 120 | 202 | 46,460 |
| 150 | 232 | 53,360 |
| 185 | 265 | 60,950 |
| 240 | 311 | 71,530 |
| 300 | 356 | 81,880 |
| 400 | 406 | 93,380 |
| 500 | 457 | 105,110 |
| 630 | 514 | 118,220 |
FAQs
- What is BS 7671? The British Standard for electrical wiring regulations, widely used for safe cable sizing.
- Why use copper cables? Copper offers high conductivity and reliability for electrical installations.
- What if my load is higher? Use a larger cable size and consult an electrician.
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