The primary distribution network carries medium-voltage electricity (usually 11 kV to 33 kV) from the distribution substation to distribution transformers. Distribution substations connect to the transmission system and lower the transmission voltage to medium voltage ranging between 2 kV and 33 kV with the use of transformers. 2 shows a typical primary distribution system. Electric power from the generating station is transmitted at high. Most distribution voltages are between 4 and 35 kV. In this article, unless otherwise specified, voltages are given as line-to-line voltages; this follows normal industry practice, but it is sometimes a source of confusion. 4kV and 33kV, depending on the demand type.
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