A measuring device of process automation technology for measuring at least one process variable of a medium. A control unit is provided, which measures the process variable at least with a predeterminable clock rate and provides the result of such measurement as a measured value. Associated with the clock rate is an energy requirement of the measuring device, wherein a display/service unit is provided, which shows the measured value and/or enables servicing of, respectively parameter input to, the measuring device. The display/service unit of the control unit of the measuring device switches from a measuring mode into a service mode, wherein in the service mode the control unit measures the process variable with a first clock rate, wherein in the measuring mode the control unit measures with a second clock rate, and wherein the first clock rate and the second clock rate are fixed in such a manner that the second clock rate is greater than the first clock rate and the total energy requirements of the measuring device in the service mode and in the measuring mode are equal.