An electrosurgical system includes an electrosurgical instrument and an electrosurgical generator. The generator includes an energy source having an active terminal and a return terminal that outputs electrosurgical energy and a controller that controls the energy source. A cable is coupled between the electrosurgical instrument and the electrosurgical generator where the cable includes a first conductor and a second conductor. The controller is configured to electrically couple the active terminal and/or the return terminal to the electrosurgical instrument using the first conductor and/or the second conductor based on whether the electrosurgical instrument is a monopolar instrument or a bipolar instrument.