performances drift and decay and structural tolerances the control system it drives the actuators establishing the duty cycle of the actuators itself in order to minimise the difference between the oven temperature target t oven target and the measured oven temperature t u2032 oven oven temperature acquisition subsystem oven probe electronic a temperature sensor provides the temperature of the cavity t u2032 oven read temperature is generally different from the actual temperature due to various contributions manufacture tolerance drift sensor decay closed loop control uses the measure of output parameters of the system to be controlled in order to establish the change of one of input parameters fig3 reports schematically a typical temperature control used for ovens in the following it will be clarifies how the system of fig3 works when there are u201c noises u201d decay drift tolerances on the oven probe and on oven heaters the control system reacts to any disturbance acting on the oven temperature acquisition subsystem oven temperature drift tolerances electronic drift tolerances modifying the duty cycle in order to keep the measured oven temperature t u2032 oven equal to the oven target temperature t oven target it 39 s clear that by modifying the duty cycle of the actuators also p in t is modified the estimated power transferred to the food p load t changes according to model 1 in the new situation the oven adsorbs actually a different p in and consequently to food also a different amount of power p load t is transferred but model 1 being based on a p in reading can keep into.