Design rules for Electrical
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Electrical
Current (3-phase): I = P / (√3 · V · pf)Voltage drop: VD = √3 · I · L · (R cosφ + X sinφ); keep ≤ 3–5%Transformer: kVA = kW / pf x diversityEarth rod: R = ρ / (2πL) · ln(4L/d)Lighting: N = E · A / (Φ · UF · MF)APFC: kVAr = kW (tanφ1 − tanφ2)DG: kVA = load kW / 0.8, checked for largest motor start
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Calculators: HT Panels & Transformer calculator · LT Panels / MCC / PCC calculator · Cable Sizing calculator · Earthing calculator · Lightning Protection calculator · Lighting calculator · DG Set calculator · Power Factor Correction (APFC) calculator
Catalogue categories: Cables, Switchgear & Panels, Transformers, Lighting, Earthing
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Standards cited by number for reference; verify designs with a qualified engineer.