An electrosurgical system for treating tissue, including a first and second electrode； a high-frequency high-voltage supply unit which can be electrically connected to first and second electrode and is designed to supply a specified treatment alternating voltage to electrodes； and a measuring unit which can be electrically connected to first and second electrode and has a measurement voltage supply module that is designed to provide a measurement alternating voltage of at least one first and second frequency, wherein the measuring unit is additionally designed to receive an electric response signal for first and second frequency via first and second electrode and determine at least one property of a tissue located between first and second electrode therefrom. The electrosurgical system relates further to an electrosurgical generator for treating tissue, to a method of operating an electrosurgical system, to using electrosurgical system and to applying the method of operating an electrosurgical system.
