DC · AC · earthing · SPD
Cable is a safety part, not a place to save two thousand rupees.
Specify tinned copper XLPO, EN 50618 / IEC 62930, 1500 V. PVC jackets sold as “solar wire” crack in 18–36 months on a Pakistani roof.
| Size | Copper PKR / m (2026) | Use |
|---|---|---|
| DC 4 mm² | 150–280 | Typical 3 kW, short strings |
| DC 6 mm² | 250–465 (FAST ~340–380) | 5–6 kW sweet spot on 645 W strings |
| DC 10 mm² | 400–645 | 10 kW / long run |
| DC 16 mm² | 700–990 | 15 kW+ |
| Battery 25 mm² | 1,200–1,700 | 48 V battery leads |
MC4
Generic pair Rs 30–120 is a fire risk. Mid Chinese 120–180. Stäubli-class 150–300. Do not mix brands on one string.
Protection
DC MCB 16–32 A 1.2–1.5k. SPD 600–1000 V 2.4–4.5k. Isolator IP66 1.8–5.2k. Schneider iC60 PV costs more and is worth it on C&I.
Earthing
Field target ≤10 Ω (some LESCO checklists <5 Ω). CNC Cu rod kit ~12.5k. ESE is a different product for structures, not a house earth.