Electrosurgical system and method for operation thereof

A supply apparatus for an electrosurgical system comprising:

• at least two neutral connections for a neutral electrode (13) and at least one working connection for one working electrode of an electrosurgical instrument respectively,
• a generator for providing a generator voltage (UG) or a generator current (IG) at a generator frequency (fg),
• a measurement signal source for providing a measurement signal (XM) alternating with a measurement frequency (fm),
• a measurement device for measurement of an impedance parameter (P) that describes an impedance (Z1, Z2) between two apparatus connections to which the measurement signal (XM) is provided,
• a switch device that can be switched between multiple switch conditions (C1, C2, C3, C4, C5), which electrically connects the measurement signal source with the two neutral connections and disconnects the measurement signal source electrically from the at least one working connection in a first switch condition (C1) and which electrically connects the measurement signal source with at least one of the working connections in a second switch condition, and
• an evaluation unit that is communicatively connected with the measurement device and configured for evaluation of the measured impedance parameter (P).