Portable Generator Sizing Chart

How to match your generator to your power demands

  1. First, discover your total electrical load, using the power chart. Make a list of all lights and electrical appliances you wish your generator to supply.
  2. Establish your steady state load - the lights and appliances you expect to operate at any one time.
  3. When electric motors form part of your appliances (see note below), calculate your maximum demand by adding the extra power required to start the electric motor to your steady state load.
  4. Choose your generator to match your maximum power demand.

Note: Electric motors need more power to start than to run. Use the simple formula of 3 x the motor horsepower to add to your required kW. For motors starting under load (e.g compressors) or submersible pumps, a higher value is required. This guide applies to modern motor design only.

(*Caution required when using sensitive electronic equipment.)

APPROXIMATE POWER CONSUMPTION CHART
APPLIANCE WATTS STARTING WATTS
Air Conditioner (caravan) 900 - 2000  
Clothes Dryer 2,400  
Computer (desktop/laptop) 800/500  
Drill 3/8" : 1/2" 475/750  750/900
Electric Motor: 1/4 hp 180 540
                       1/2 hp 375 1,125
                       1 hp 750 2,250
                       2 hp 1,500 4,500
 Hot Water Heater (caravan)  1,500  
 Iron  900 - 1,200  
 Kettle or Jug  1,600 - 3,000  
 Lights  60 - 200  
 Microwave Oven  60 - 1,200  900 - 1,600
 Radiator  1,000 - 2,500  
 Refrigerator  200 - 500  
 Refrigerator (caravan)  100 - 250  
 Television Set  200  
 Toaster  750 - 1,250  
 Washing Machine  500 - 1,000  500 - 3,000
 Welder 140 amps  4,000  
 9’ Angle Grinder  2,300  
 Conversion Table
Use these recommendations as a guide only as output can vary from appliance brand and models. To convert watts to KVA @ 0.8PF, divide watts by 0.8 (eg; 2,000 watts = 2.5KVA , 3,000 watts = 3.75KVA , 4,800 watts = 6KVA .) To convert KVA to kW @ 0.8PF, multiply KVA x 0.8. 1000 watts @ 240 volts = 4.17 amps approximately.

Choose from the rugged, reliable ready-to-go cummins portable range

CUMMINS MODEL APPLICATION OUTPUT (watts)
CAMPING P1100 Caravan & Camping - Runs a caravan fridge, T.V. and lights all at the same time 700
INVERTER P1700i Caravan & Camping - All the P1100 powers plus a Tuckerbox freezer or microwave oven 1400
P3200ie Caravan air conditioner, coffee machine, bread makers etc. Sensitive equipment up to 2800 watts 2800
P4300ie Ideal quiet home or office back up power, small mobile van power etc. Sensitive equipment up to 3800 watts 380
COMMERCIAL P2200 Light General Use - 0.75 hp motors, lighting and power tools up to 2,000 watts 2000
P2600 Light General Use - 0.75 hp motors, lighting and power tools up to 2,500 watts 2500
P4500 Medium General Use - Power tools up to 4,000 watts 4000
PX4800e Medium General Use - 9" Anglegrinder, small air conditioners, power tools up to 3,500 watts 3500
P5000e General Use - 2 hp motors, most 140 amp welders, air compressors, multi-head shearing plant 5000
PX6100e Medium General Use - Power tools up to 4,400 watts 4400
PX7500e General Use - 2 hp motors, most 140 amp welders, air compressors, multi-head shearing plant 5500
PX12000e General Use - 5 hp motors, most 250 amp welders, compressors or a wool press 8500