A method for regulating the speed of an internal combustion engine. The detecting circuit outputs a detecting signal according to a reference signal and an oscillating signal. The system also includes a handle which releasably connects together the control tip, pusher, and delivery cannula to permit limited longitudinal motion between the control tip and the delivery cannula, and between the pusher and the delivery cannula. The protection signal may be derived from the over-voltage condition independent of whether a supply of power to the device is present. The geometrical configuration is for engagement with an annular rib on an attachment ring.