4.3.4example2
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A step-down transformer with a ratio of 25:1 and a primary voltage rating of 6.6kV is used to reduce the voltage from a 6.6kV line experiencing a drop to 6270V due to distance and load. Calculating the secondary voltages, the principal tap outputs 250V and the -5% tap outputs 264V to maintain the rated output with a 5% lower input voltage.
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4.3.4example2
- 1. Example 2 Consider the situation where the 6.6 kV line has voltage drop due to distance and load. In this case, a step down transformer has a ratio of 25:1 and a rated primary voltage of 6.6 kV. If the primary voltage is 6270 V, calculate the secondary voltage: At the principal tap, and at the -5% tap, and (a) E 2 at principal tap V 2 = 6270 = 250 V 25
- 2. Example 2 Consider the situation where the 6.6 kV line has voltage drop due to distance and load. In this case, a step down transformer has a ratio of 25:1 and a rated primary voltage of 6.6 kV. If the primary voltage is 6270 V, calculate the secondary voltage: At the principal tap, and at the -5% tap, and (b) -5% the turns ratio 95 x 25 = 23.75:1 100 E 2 at -5% tap V 2 = 6270 = 264 V 23.75 Note that the 264 V secondary output voltage is the nominal voltage with rated voltage and the principal tap. That is, the negative percentage tap is designed to give rated output voltage with that percentage of voltage drop in the primary supply voltage.