Inverters and off-line UPS' are very similar. Inverters are supplied with a separate battery bank while UPS', only the smaller ones, have the batteries built into the unit.

A specific rated UPS will be supplied with a matching battery pack while Inverters are supplied with DC power cables that must be connected to a battery. Small inverters (150 watts) used for recreational purposes are normally connected to a car's cigarette lighter socket. Bigger units up to 600W are supplied with DC connection cables that must be firmly connected directly to a battery and units above are wired directly to a battery with specified cable sizes. Different cable sizes are recommended by different suppliers. The rule of thumb here is to use the thickest cable available over the shortest length possible.

Most vehicle batteries will provide an ample power supply for 300W Inverters, 30 to 60 minutes. Larger Inverters use deep cycle batteries which will give you several hundred complete charge/discharge cycles. Read the section on batteries for more information.

Two types of Inverters are available, click here to find out more about Pure Sine-wave and modified Sine-wave Inverters.