The convert input must be able to accept power at line voltage. Although AC line voltage is commonly referred to by its
RMS value, such as 120V or 240V, the peak voltage of the sine wave is around ±170V for 120V RMS and ±339V for 240V RMS. Additionally, 120V and 240V are considered
nominal voltages; the actual voltage provided by a utility may be somewhat higher or lower during normal operation. The range of this variability is generally within the ±5% range required by ANSI standard C84.1 (114126V and 228252V respectively). This pushes the peak line voltage up to ±178V for 120V and ±356V for 240V. Off line regulators must also be tolerant of voltage spikes, surges, brownouts, and other
power quality conditions that may affect the electronic device. == References ==