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Just Generators

The UK's Number 1for Generators and Power Equipment
Call us for expert advice: 01263 820202
We offer FREE UK Mainland delivery for orders over £50 (terms apply)

Buying the right generator can seem like a formidable task.

But in just a few easy steps you can effectively and confidently decided and choose which generator is right for you.

  • Identify the tools and appliances you wish to operate with your generator.
  • Determine the required power for each item ( see appliance data plate i.e.: watts of appliance).
  • Add the required Watts of each item that will be running simultaneously. Also allow for motor starting of appliance * see chart
  • Choose the generator that has rated Watts that meet or exceed this total power.

Motor Starting is an important consideration when buying a generator. Keep in mind that induction type motors, like those that run sump pumps, refrigerators and compressors , typically require 2 to 3 times their listed running watts to start.

Opposite is a chart you can use to determine how many Watts you will need to start up motors of various sizes and types.

Please note that power tools using a universal commutator do not require any additional start up power.

The table opposite lists tools and appliances you may want to use with your generator.

With each tool or appliance is listed the approximate running watts for each.

Always consult the data plate on the tool or appliance for accurate electrical information. The outlet configuration of some units may require modification to achieve maximum rated power.

EQUIVALENT MAX kVA: Some Manufacturers give ratings in kVA by adding 25% to the power rating. This figure is for comparison with these values.

See Power Calculator



Motor Size H/P Running Watts Watts Req. To Start Motor
1/8 275 850
1/6 275 850
1/4 400 1,050
1/3 450 1,350
1/2 600 1,800
3/4 850 2,600
1 1,100 3,300
2 2,200 6,600

Machines & power required to run

Fluorescent Lamp 60
Light Bulb 100
Video 100
Palm Sander 175
Fridge* 200
Slow Cooker 200
Radio/Hi Fi 200
Colour TV 250
Central Heating Pump 300
VDU 300
Strimmer 10" 350
Printer 350
Jig Saw 400
Bench Grinder 400
Computer 400
13mm Drill 450
Orbital Sander 450
Hedge Trimmer 500
Flood Lamp 500
4" Angle Grinder 550
1/3 HP Airless Sprayer 600
Telefax 600
13mm Hammer Drill 600
Deep Freeze 700
Planer 700
5" Angle Grinder 750
Hair Dryer 1,000
Lawnmower 10" Hover 1,000
5" Circular Saw 1,000
Router 1,000
Belt Sander 1,020
Vacuum Cleaner 1,100
Coffee Maker 1,200
Steam Iron 1,250
Cement Mixer * 1,320
Chain Saw 10"-16" 1,500
600W Microwave 1,500
Portable Heater 1,500
Hot Air Gun 1,500
PhotoCopier 1,600
8" floor sander 2,000
Compressor * 2,200
12" Angle Grinder 2,500
Hammer Drill 2,500
Kettle 2,500
Fan Heater 3,000
Hammer/Breaker 3,000
1 HP Pressure Washer 3,500
Arc Welder- 130A 3,500
Washing Machine 4,000
* See Motor Starting
Copyright © 2017 Calgary Just Companies Ltd. All Rights Reserved. Registered in England No. 04338715. VAT Number GB 785469862.