Calculate Generator kVA Rating, Fuel Consumption & Cable Size
💡 Formula: kVA = (Load × PF) / Efficiency | Recommended kVA = kVA × (100% + motor factor)
kVA = (W × PF) / Eff | Fuel = 0.2 × kVA × Hrs (Diesel)
📖 Generator Size Calculator
This tool helps you select the right generator for your application. It calculates the required kVA rating, fuel consumption, and cable size based on your load, power factor, motor starting requirements, and altitude. Essential for backup power planning and industrial generator selection.
📐 Generator Sizing Formulas
Generator kVA: kVA = (Load × PF) / Efficiency Motor Starting kVA: kVA_start = (Motor kW × PF × Start Factor) / Eff Fuel Consumption (L/hr): Fuel = 0.2 × kVA (diesel) Cable Size: Based on current and distance
📊 Standard Generator Sizes
kVA
kW (PF=0.8)
Typical Application
Fuel (L/hr)
5
4
Small Home
1.0
10
8
Home + Small Office
2.0
20
16
Medium Home
4.0
30
24
Large Home / Shop
6.0
50
40
Small Industrial
10.0
100
80
Large Industrial
20.0
200
160
Large Commercial
40.0
500
400
Heavy Industrial
100.0
📌 Generator Sizing Recommendations
Calculate running load: Sum of all continuous loads
Consider starting current: Motors require 3-7× running current
Add 25-30% margin: For future expansion and peak loads
Altitude derating: Generators lose capacity at high altitude