Abstract: The HF-current generator of an electrosurgical apparatus has one terminal connected to an active electrode and an additional terminal connected to a neutral electrode. The neutral electrode consists of at least two partial electrodes which are individually connected via connecting leads to respective current meters for measuing the partial currents in the respective connecting leads. The output side of the current meters are connected to a logic element that is provided for combining the partial currents and which provides a logic signal that is a function of their combination. A ratio generator is preferably provided as the logic element to develop a logic signal that is a function of the ratio of the partial currents. A comparator for comparing the logic signal with pre-set limit value is associated with the logic element. The output signal of the comparator is used as an alarm signal to actuate an alarm or a protective means for a patient in contact with the neutral electrode.

Abstract: A split neutral electrode useful for electronic surgery, consists of at least a first and a second partial electrode separated from each other by an insulating strip. An electrical resistance establishes an electrical connection between the partial electrodes. Each partial electrode preferably has a protrusion which is wrapped around and makes forced contact with the resistance. An associated terminal clamp constructed in the form of an alligator clip contains two metal overlays which are brought into contact with the protrusions upon closure of the clamp.