When low voltage is called alternating voltages up to 1000 V and DC voltages up to 1500 volts. The range of low voltage includes not only low voltages, for example, the power supply used in the low voltage network of 400 volts between the three phases and 230 volts between each phase conductor and the neutral conductor. Legal regulations of low voltage installations within the EU are set out under the Low Voltage Directive.
Higher voltages are referred to as high voltage, which is divided in the field of electrical power engineering in the field of medium voltage, high voltage and extra high voltage. The limits are not clearly defined here.