Abstract: A high-frequency surgical appliance has a peak value detection and control unit, having a current or voltage sensor designed to detect the current strength or the voltage of a high-frequency alternating current output to the load. The control unit has a root-mean-square value former or is connected thereto, connected to the sensor and forms a root-mean-square value of a high-frequency alternating current detected by the sensor. The control unit deactivates the high-frequency generator when, in the steady state of the HF high-voltage circuit, a quantity of an instantaneous peak value of a signal representing an instantaneous value of the high-frequency alternating current detected during operation by the sensor exceeds a quantity of a value derived from the root-mean-square value of the high-frequency alternating current detected during operation by the sensor. The sensor continuously detects the instantaneous value of the current or voltage flowing during operation into the HF high-voltage circuit.

Abstract: An electrosurgical system for generating high-frequency alternating current for an ablation of body tissue, containing a high-frequency voltage supply unit which is or is to be electrically connected to a first and second electrode, and which is configured to supply the electrodes with a high-frequency alternating voltage. The electrosurgical system further includes a feedback unit which is electrically connected to the first and second electrodes and which is configured to generate and transmit an output signal dependent on the electrical resistance between the first and second electrodes. The electrosurgical system also includes a control unit that is configured to control the high-frequency voltage supply unit in such a way as to be able to automatically switch between at least one first and one second operating mode.

Abstract: A high-frequency surgical appliance has a peak value detection and control unit, having a current or voltage sensor designed to detect the current strength or the voltage of a high-frequency alternating current output to the load. The control unit has a root-mean-square value former or is connected thereto, connected to the sensor and forms a root-mean-square value of a high-frequency alternating current detected by the sensor. The control unit deactivates the high-frequency generator when, in the steady state of the HF high-voltage circuit, a quantity of an instantaneous peak value of a signal representing an instantaneous value of the high-frequency alternating current detected during operation by the sensor exceeds a quantity of a value derived from the root-mean-square value of the high-frequency alternating current detected during operation by the sensor. The sensor continuously detects the instantaneous value of the current or voltage flowing during operation into the HF high-voltage circuit.

Abstract: Electrosurgical instrument including a handpiece which has a connection side (A) and a treatment side (B), and including a connecting plug which is electrically connected to the connection side (A) of the handpiece and is electrically connectable to a high-frequency generator, wherein the electrosurgical instrument includes a control unit which is designed to actively control the voltage waveform of high-frequency energy which is output on the treatment side (B) of the handpiece.