Realiability, FIT-rate, Risk of Failures: The probability of component failures within a certain number of component hours is described as the so-called FIT-rate ("Failures In Time"). It depends on external factors (operating conditions: voltage, current, temperature, humidity, etc.) as well as internal factors (material, technology). The effects of external factors on the FIT-rate can be evaluated and controlled by means of our FIT diagrams (stated in our catalogues and special data sheets).