PV inverters convert the DC power generated by photovoltaic panels into AC power for commercial, domestic, and industrial use. A failure of the inverter stops the supply of power, regardless of the amount of power generated by the solar panels. For this reason, of all the components of a PV system they rank alongside the panels as key components that require high reliability. Particularly common are outdoor installation types for small- to mid-capacity range residential and industrial use (depicted at right). These are often installed in harsh environments where they are exposed to rain and snow. It is necessary to take measures so that reliability is not impaired even in such environments.