Patent ID: 7160293

Claim:
In an electrosurgical generator including at least two pairs of patient return pads adapted for contacting a patient, each pair of said at least two pairs of patient return pads having two conductors attached to a corresponding patient return pad for connecting the pad to a source of a.c. energy passing through the pad, a method for controlling the electrosurgical generator comprising the steps of: producing and applying a corresponding current signal for each of said at least two pairs of patient return pads; producing at least one signal by resonant circuitry means responsive to the impedance between at least one pair of patient return pads; and receiving said at least one signal for determining the impedance between said at least one pair of patient return pads, wherein the frequency of said corresponding current signal for each of said at least two pairs of patient return pads is substantially equal to the frequency of at least a portion of said resonant circuitry means.