These calculators will assist you in determining what size generator you may require or how to convert one unit of electricity to another.

Calculating Ampere (I), given kVA

Phase
1, 2, 3
Generator
kVA
Volts
Required
= Ampere
I
Converting kVA to kW
kVA = kW
Converting kW to kVA
kW = kVA
Converting kW to HP

kW

=

HP


What size genset is needed to start a 3 phase electric motor Direct on Line (DOL) start
HP of
Motor
= Generator
kVA Required

Generator Size to Start Motors

Instructions: You only need to fill in the columns coloured in orange.
Fill in the HP of the motor(s) in their starting squence, select the start method (Direct On Line or Star Delta) and press Evaluate. The required generator size will then be displayed at the bottom.

3 Phase (415 volt @ 50Hz)
1 Phase (240 volt @ 50Hz)

Starting
Sequence

Motor HP

Start Method
DOL / StarDelta

Run
Variable

Phase
Current

Starting
Value

Total Run
Current

Total Start
Current

1 /
2 /
3 /
4 /
5 /
6 /
Generator Size for Starting with: kVA*
Generator Size for Running with: kVA*
Generator Size Recommended: kVA*

Domestic Power Guide

Appliance Rated Watts Rated kVA Rated kVA
Appliance Gene to run appliance Gene to start appliance
Air Conditioner (Evap model) 275-1000 0.34-1.25 1.36-5
Air Conditioner (Rev cycle) 200-2500 0.25-3.13 1-12.5
Clothes Dryer 2400 3 3
Coffee Percolator 550 0.69 0.69
Can Opener 100 0.13 0.52
Deep Freezer 500 0.63 2.52
Disposal Unit 650 0.81 3.24
Dishwasher 1000-3000 1.25-3.75 1.25-3.75
Domestic Water Pumps 275-1000 0.34-1.25 1.36-5
Exhaust Fan 40 0.05 0.2
Food Processor 500 0.63 2.52
Fry pan 1400 1.75 1.75
Hair Dryer 1500 1.88 1.88
Hot water Service 2500-3000 3.13-3.75 3-13-3.75
Iron 800-1500 1-1.88 1-1.88
Kettle or jug 1600-3000 2-3.75 2-3.75
Lights 25-200 0.03-0.25 0.03-0.25
Microwave 1500 1.88 1.88
Oven 4000-8000 5-10 5-10
Radio 60 0.08 0.08
Radiator 1000-2500 1.25-3.13 115-3.13
Refrigerator (home) 300 0.38 1.52
Sewing Machine 60 0.08 0.32
Space Heater 2000 2-5 2.5
Television 75-200 0.09-0.25 0.09-0.25
Toaster 250-1250 0.3-1.56 0.3-1.56
Washing Machine 500-3000 0.63-3.75 2.52-15
Welder 140A 5000 6.25 8 min

Guide to units:
HP = Horsepower
kW = Kilo Watts
kVA = Kilo Volt Amps
I = Ampere or Current
V = Volts
PF = Power Factor