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What is vector group of transformer?

Vector Group of Transformers                     • A vector group is the International Electrotechnical Commission (IEC) method of categorizing the high voltage (HV) windings and low voltage (LV) winding configurations of three-phase transformers.                      • Vector group is a connection of primary winding , secondary winding and an electrical angle difference .                      • The vector group designation indicates the windings configurations and the difference in phase angle between them. The three phase transformer windings can be connected several ways. Based on the windings’ connection, the vector group of the transformer is determined. •              The transformer vector group is indicated on the Name Plate of transformer by the manufacturer. The vector group indicates ...
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Battle of Thermoplyae 480 BC

               Leonidas was a warrior king of Sparta, one of the most dominant ancient Greek cities. He was not destined by birth to become king at all, and did so only because his older half-brother Cleomenes died without male issue. During his reign, King Xerxes of Persia sought to conquer all of Greece, after his father’s failed attempt. By 480 BC, Xerxes had built up an enormous army of some one hundred and fifty thousand men and a navy of six hundred ships. The invasion led to the Battle of Thermopylae, which is considered one of the most famous battles in European ancient history. Unlike other battles, however, it was not a victory for the Greeks, but a defeat. Its fame is derived from being one of the most courageous last stands by the vastly outnumbered defending army of Greek city states led by King Leonidas of Sparta against the invading Persians under King Xerxes.                 The Greek fo...
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Eclipses

What is Eclipse?  .                        When the light of the sun or the moon is obscured by another body the sun or moon is said to be in eclipse . Lunar Eclipse . When the earth comes between the sun , the shadow cast by the earth on the moon results in a lunar eclipse . Lunar eclipse  occurs only on a full moon day but not on every full moon day . Solar Eclipse . When the moon  comes between the sun and the earth , it causes obstruction of the sun's light when viewed from earth , and is called solar eclipse . A solar eclipse occurs on a new moon day when the moon is in line with the sun . However , solar eclipse does not occur on every new moon day .
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