In some distribution lines, the voltage around the end of distribution line rises more than the regulation voltage. One of the reasons is the Ferranti effect caused by excessive amount of static capacity （SC）in high voltage（HV）consumers. The designed amount of SC has been conventionally recommended to be equal to about 1/3 of three-phase transformer capacity. In recent years, however, load power factor of consumers has been improved due to introduction of the power electronic equipments, i.e. motor control systems, lights with electronic ballast, and so on. In order to adjust the amount of SC it is desirable for HV consumers to install automatic power factor controller（APFC）. However, it is actually difficult from the viewpoint of cost. Therefore, it is important to design the appropriate amount of SC. In the pape, authors clarify the present condition of SC and power factor in HV consumers. Then the appropriate amount of SC necessary to maintain the voltage at receiving point reasonable is proposed based on the analysis of measurement results at various HV consumers. Moreover, authors evaluate the effectiveness of the proposed amount of SC from simulation of distribution system model.

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