1-2020 defines high voltage as 115 kV to 230 kV, extra-high voltage as 345 kV to 765 kV, and ultra-high voltage as 1,100 kV. Specifically, ANSI C84. The International Electrotechnical Commission and its national counterparts (IET, IEEE, VDE, etc. However, the term "HV" can also refer to voltages as low as 50 volts in some safety. These requirements vary depending on whether the electrical equipment is rated at (1) 1,000 volts or less (See, Article #2) or (2) over 1,000 volts. Minimum clearances in front of electrical equipment (600 V (now 10000 V) or. British Standard BS 7671:2008 defines high voltage as any voltage difference between conductors that is higher than 1000 VAC or 1500 V ripple-free DC, or any voltage difference between a conductor and Earth that is higher than 600 VAC or 900 V ripple-free DC. In international standards, levels above 1000 V AC and 1500 V DC fall into the high-voltage class, and special insulation, equipment and safety rules apply to these voltages.
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