In distribution networks, grid operators need to prevent voltage violations when photovoltaic generation increases. As a countermeasure, they apply sophisticated updating of the control parameters of on-load tap changers (OLTCs). Furthermore, to upgrade the grid operation, the measurement granularity of smart meters has been altered from 30-minute increments to shorter times. However, in terms of data communication load reduction, only a few smart meters need changes. In this study, we evaluate the effect of smart meter data with short measurement granularity on the voltage control performance of an OLTC. As a method of programming consumers to acquire data every 5 min, we selected the consumers measuring the high or low voltage among the past measured database. The numerical simulations showed that voltage violations occurred with control parameters using 30minute measurement data. However, this could completely be avoided by using 5-minute data.