In the context of voltage converters, a sinusoid describes the shape, or waveform, of the output AC voltage. It is an ideal, smooth and regularly repeating curve that is identical to that found in a normal household electrical outlet. The purpose of a voltage converter is to convert direct current, for example from a battery, into alternating current, which can be used to power common appliances. So-called 'pure sine wave' converters produce a voltage that is virtually indistinguishable in quality from the public grid. This makes them suitable for powering all types of appliances, including those sensitive to power quality. These include modern electronics such as computers, televisions and medical devices, as well as appliances with electric motors such as refrigerators and pumps. There are also inverters with a so-called "modified sine wave" whose output voltage only approximately mimics the ideal curve and has a rather stepped shape. Such voltages may be unsuitable for sensitive devices and may cause them to malfunction, overheat or make disturbing noises. Therefore, choosing a sine wave inverter ensures that the powered device will operate as reliably as if it were plugged into a standard power outlet.
