Generators Buyer's Guide

Also see articles on:
- How does a Generator Work?
- Diesel Vs Petrol Generators
- How to Drain a Generator of Fuel

A generator works by a motor driving an electrical magnetic field called an alternator. The size of the alternator and motor dictates how much power can be generated.

Generators come in all shapes and sizes from small 700Watts (0.7kw) to our larger units that are 5000Watts (5kw) and larger. Some generators are very large indeed and can power small factories, industrial estates, hospitals, schools, businesses etc. These can supply power measured in MegaWatts.

There are many situations when you need electricity somewhere away from the mains supply. Machine Mart supply two main types of generator. Generators and Inverter Generators. Generators produce electricity by using petrol or some other fuel source to create a fluctuating AC current between -230V and 230V.

Why use an Inverter Generator with Sinewave Technology?

Simulated Sinewave
This creates a simulated sinewave current which resembles castle battlements. This sharp fluctuation in current can be overpowering for sensitive instruments and devices. 

Sinewave
In such cases, an inverter generator would be used. An inverter generator works between the same minimum and maximum voltage but at a more controlled, gradual output, producing a sinewave. This resembles a continual wave and prevents devices from being damaged by a sudden surge in power.

When deciding which type of generator best suits your needs there are a number of things you should take into account.

• The amount of power required by whatever device you want to use - Voltage and Ampage. See guidelines on table below.
• The environment in which you will be using it – Does it need to be quiet or non-polluting?
• How long and how often will you be using it?
• Do you need to be able to move the generator around?

GENERATORS
Machine Mart offer a selection of generators which run on either petrol, diesel, or a combination of petrol and propane or LPG, in a dual fuel generator. They are capable of supplying from 700Watts to 6500Watts (0.7kVA to 6.5kVA). Some are suitable for occasional use, and some are designed for continuous use. If you are looking for a generator for leisure use – camping, caravanning or boating there are several super-quiet models to choose from. For commercial and industrial use, there are larger machines – with less sound proofing, which are able to supply a much greater output.  When picking a generator, things to look out for are:

• Maximum output – (kVA or Watts) will it be powerful enough for your needs?
• Output Voltage – Do you need 12Volt, 110Volt or 230Volt output?
• Start method – Electric or Recoil (with a pull cord)
• Run-time – How big is the fuel tank?
• Sound output – Do you need a quiet generator?
• Fuel used – Petrol, Diesel or Propane?
• Output socket type –13Amp 3 pin socket, Blue 230V and Yellow 110V industrial or 12V cigarette lighter socket.

POWER INVERTERS
Power Inverters can be used to power mains voltage items in your vehicle or boat, now you can take almost anything you can think of and use it on the move (Subject to legal guidelines) – Laptops, Shavers, Digital Radios, Games consoles, TVs, Power tools, etc.

An inverter will take a 12Volt, direct current supply, from a car or leisure battery, for example and turn it into 230Volt, alternating current supply. As you might expect, the greater the output you require from your inverter, the greater the drain on your battery.

All Machine Mart inverters have at least one 13Amp square pin socket and some have USB sockets making them suitable for charging phones, laptops and powering consoles, laptops, and many other domestic appliances. The majority of inverters plug into the 12Volt socket in your vehicle. Larger models may be hardwired into your boat, caravan or motorhome. Invertor Generators are silent in use and therefore ideal in sensitive situations. As with generators, you should buy a model with sufficient output to power whatever you need to attach to it.

CALCULATING VOLTS, WATTS and AMPS

To calculate the wattage of an item multiply the Amps by the Volts v x a = w
To calculate Amps – w ÷ v = a
To calculate Volts – w ÷ a = v

Use this as an approximate guide to the power required from your power source. 

*These items need a regulated power supply which makes sure the current supplied is suitably “smooth” for the delicate electronic circuitry.

‡Items with this symbol may require a higher starting current - please check before buying a specific generator or other power source.

Also see our article on How does a Generator Work?