Choosing a Generator

In order to choose a suitable generator for your intended purpose, you should consider power output, fuel and engine type, electrical phase, voltage and socket types.

Maximum power and rated power

Maximum power can be obtained from a generator, although the efficency under this condition would only be 50%, the other half wasted as dissapated as heat. For this reason generators are not usually opperated at maximum power, but at a lower rated power where efficiencu is much greater.

Single phase and three phase

Generally domestic appliances are single phase. Power is generated and distributed as three phase, and is split before entering domestic houses. Apart from distribution, three phase electricity has applications in industry..

Kilovolt volt-amps (kVA) and kilowatts (kW)

Volt-amps are a unit of apparent power, and watts are a measure of actual power. In a resistive load the two values are equivalent.
1 Kilowatt is equal to 1000 watts

Resistive loads and reactive loads

An incadesent bulb is an example of a resistive load, and has a constant power requirement. Electric motors, and appliances that contain them, on the other hand require more energy whilst they start up. Typically 3 times more power.

To calculate your power requirements, you should consider the total power used by appliances and tools that will be operated at the same time, including reactive loads of motors.
Choose a generator which has a rated power, equal or greater to this. The table below is a guideline of the power requirements of various appliances.