Patent ID: 6984231

Claim:
An electrosurgical system including a generator for generating radio frequency power, and an electrosurgical instrument including at least three electrodes, the generator comprising (i) a radio frequency output stage having at least a pair of radio frequency output lines, (ii) a power supply coupled to the output stage for supplying power to the output stage, (iii) a controller capable of varying a radio frequency signal supplied to the radio frequency output lines, and (iv) a switching circuit having at least three output connections each in electrical connection with a respective one of the at least three electrodes, and operable to vary the connections between the radio frequency output lines and the three or more output connections, the system further including a switching device operable to send a signal to the switching circuit within the generator in order to vary the electrode or electrodes to which radio frequency power is supplied, the switching device also causing a signal to be sent to the controller such that the radio frequency signal supplied to at least one of the three or more output connections vanes depending on the electrode or electrodes to which radio frequency power is supplied, one arrangement of the switching circuit being such that one of the electrodes has no direct connection to the output stage of the generator and is connected via a capacitor to another of the electrodes.