More and more energy is fed especially by decentralized converters from renewable energy sources into the grid. Therefore, it is important to know the grid behavior at a wide frequency range from the fundamental frequency up to the kHz-range. This paper presents an advanced impedance medium-voltage measurement system with a high frequency range for an electrical medium-voltage grid. A sinusoidal current of a predefined frequency is injected into the grid. With this, the grid impedance is calculated from the measured magnitude and phase of the injected current and the resulting voltage. The measurements will be executed at different frequencies to produce approximate continuous impedance versus frequency characteristic of the grid at the measured coupling point. Results of a ready to use, low-voltage impedance measurement system are discussed, and the design considerations the basic concept and first simulation results of the developed medium-voltage system are presented in this paper.