How to Size a Generator for Your Site (No More Power Trips)

Undersized generators cause tripping and equipment damage. Oversized units waste fuel. Here’s a quick method to choose the right kVA for your load.

Step 1 — List All Loads

• Concrete mixer: 2–3 kW
• Air compressor: 4–7 kW
• Angle grinders & drills: 1–2 kW
• Tower lights: 1–2 kW each

Step 2 — Apply Diversity & Starting Currents

Motors need more power on startup. Multiply motor loads by 1.5 × to cover inrush. Add a 20% headroom for future tools.

Step 3 — Convert kW → kVA

Use kVA = kW / PF. For sites, assume PF ≈ 0.8. Example: total 12 kW → 12 / 0.8 = 15 kVA.

Pro tip: If you’re running welders or large compressors, call us and we’ll size a generator with proper surge allowance.