【Electrical Version】Daily Question 20171024
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This post was last edited by hesonchang214 on 2017-10-26 09:45. The voltage during the operation of a transformer should not exceed （） of the rated voltage. A、±2.0% B、±2.5% C、±5% D、±10%
**The allowable voltage deviation specified by the standards is as follows: a) For systems powered at 35 kV and above, the sum of the absolute values of the positive and negative voltage deviations shall not exceed ±10% of the rated voltage； b. For three-phase power supply of 10 kV and below, the allowable voltage deviation is ±7% of the rated voltage. ? c. For 220-volt single-phase supply, the allowable voltage deviation is +7% and -10% of the rated voltage. (238V—198V)