In order to increase the reliability of the systems, certain
operations requiring extra investment might be necessary such
as increasing component reliability, backing up the
components, to reduce the maintenance time, increasing the
options and the frequency of measurements and observations.
By evaluating the financial dimension of the method to follow,
the cost of reliability in general or per unit can be calculated.
The cost of reliability per unit decreases when it reaches a
certain value. When the risk of insufficient reliability for those
using this system is considered, the dotted lines given in
Figure 1 can be calculated as the minimum cost to ensure a
certain level of reliability.