Safety extra-low voltage

According to IEC 61140, a safety extra-low voltage is an AC voltage of no higher than 50VAC or 120V smoothed DC voltage. The technical abbreviation for this is SELV (safety extra low voltage), and there are also special forms such as PELV and FELV. A safety extra-low voltage is not necessarily a touchable voltage, as the values for touchable voltages are set at max. 25VAC or 60VDC.