Choosing the right Generator for your needs
Generators fall into 2 basic groups
Leisure and Home use
Industrial/Site use
There are certain key features that you will need your Generator to have when selecting a product for either of these groups.
Leisure and Home use.
This is a generator that will typically be used either in camping, caravan, small exhibition situations and around the home and office. Key features required will include silent or quiet running, weight and size, ease of transportation, run time, 230volt and 12volt output and maybe Inverter technology*
Industrial/Site use.
This is a product that will typically be used in the work place or on site where the output is restricted to 110volt. Key features again can also be silent or quiet running, ease of transportation, low oil warning systems, three phase supply, petrol or diesel powered, run time and very importantly robustness.
Inverter Technology*
If you are powering a TV, computer or other appliances requiring stable voltage and frequency output then it is advised that you choose a generator featuring Inverter technology* We suggest you check with the generator manufacturer.
Calculate Total Power Output Required.
Once you have decided the type of generator that best meets your needs you then need to calculate the power output that you require depending on the appliances that you intend to use. This task may seem a little daunting but is actually quite simple. The following 4 steps will help you achieve this.
A. Identify the tools and appliances that you will power from the Generator
B. Determine the required wattage for each item.
C. Total the wattage required to power your identified items simultaneously. (Allowing extra for motor starting). However, if you have an appliance with a high wattage but will not be used continuously this can be considered in your calculation. (Example) When in your caravan, turn your lights and TV off when you need to use the microwave!!
D. Choose a Generator that has continuous rated watts that meets or exceeds this total.
Wattage Table.
To help you identify the wattage of the tools and appliances that you need to power from the Generator please use this table. However, please note that the watt’s shown are only an average recommendation, therefore please check your items before use.
Appliance |
Watts |
Fluorescent Lamp | 35w |
Light Bulb | 40/60/100w |
Control Heating Pump | 100w |
Video* | |
Palm Sander | 175w |
Radio / Hi-Fi | 200w |
Refridgerator** | |
Slow Cooker | |
Colour TV* | 250w |
VCR* | 300w |
Printer | 350w |
String Trimmer | |
Bench Grinder | 400w |
Computer* | |
13mm Drill | |
Jigsaw | |
Orbital Sander | 450w |
Floor Lamp | 500w |
Hedge Trimmer | |
4" Angle Grinder | 550w |
1/3 HP Airless Sprayer | 600w |
13mm Hammer Drill | |
Telefax | |
Deep Freezer** | 700w |
Hammer Drill | |
Planer |
Appliance |
Watts |
5" Circular Saw | 750w |
5" Angle Grinder | 1000w |
Hairdryer | |
Lawn mower 10" Hover | |
Router | |
Belt Sander | 1050w |
Vacuum Cleaner | 1100w |
Coffee Maker | 1200w |
Steam Iron | 1250w |
Cement Mixer | 1320w |
10-16" Chain Saw | 1500w |
600w Microwave | |
Hot Air Gun | |
Portable Heater | |
Photocopier | 1600w |
8" Floor Sander | 2000w |
Air Compressor** | 2200w |
12" Grinder | 2500w |
Kettle | |
Fan Heater | 3000w |
Hammer/Breaker | |
Arc Welder -130A** | 3500w |
1HP Pressure Washer | |
Washing Machine | 4000w |
** MOTOR STARTING
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 2-3 times their listed running watts to start. Below is a chart you can use to determine how many watts you will need to start up motors of various sizes and types.
Note: Power tools using universal commutator motors do not require additional startup power.
Starter Chart |
||
Motor Size |
Watts |
Watts Required To Start Motor |
1/8 HP | 275w | 850w |
1/6 HP | 275w | 850w |
1/4 HP | 400w | 1050w |
1/3 HP | 450w | 1350w |
1/2 HP | 600w | 1800w |
3/4 HP | 850w | 2600w |
1 HP | 1110w | 3300w |
2 HP | 2200w | 6600w |
Convert kVA to watts
For DC application: 2.0 kVA = 2.0 kW or 2000 watts.
For AC equipment, it depends on the power factor (PF)
kVA x PF = kW.
kW x 1000 = watts.
Resistance type loads have a power factor near 1.00, so 2.0 kVA = 2.0 kW or 2000 watts.
Motors may have a power factor closer to 0.85.
In that case 2.0 kVA x 0.85 = 1.7 kW or 1700 watts.