A high frequency power supply for applying electrical energy to a target site on or within a patients body is described. The power supply includes an electrical output driver and an output current sensor for detecting the current output from the electrical output driver. A power limiting device is coupled to the current sensor, wherein the power limiting device moves from an operating mode to a standby mode by reducing power from a first operating power level to a second standby power level on the output driver when current output from the output current sensor exceeds a predetermined threshold level. The supply also includes a periodic detection device for continuously detecting current output in the standby mode without increasing the power to the first operating power level.
