Parametric RDA Folio Plots
Weibull++ includes several plot types you can use to visualize the results of your parametric RDA analysis. You can create plots by choosing Recurrent Event Data > Analysis > Plots or by clicking the icon on the Main page of the control panel.
The following is a description of the different types of plots that can be created in a parametric RDA folio. (For general information on working with plots, see Plot Utilities.)
- Cumulative Number of Failures plots the failure times in the x-axis and the cumulative number of failures in the y-axis. The points represent the actual failure times in the data set and the line represents the expected cumulative number of failures based on a simulation using the calculated model parameters. This gives you an indication of how the number of failures is increasing over time.
- Cumulative Failure Intensity vs. Time plots the average rate of occurrence of failures over a period of time. The points represent the cumulative failure intensity calculated at each failure time in the data set and the line represents the cumulative failure intensity based on a simulation using the calculated model parameters. This shows how the rate of occurrence of failures increases, decreases or remains constant for that period of time.
- Instantaneous Failure Intensity vs. Time plots the rate of occurrence of failures over several instances of time. The line represents the instantaneous failure intensity based on a simulation using the calculated model parameters. This plot may be used to show how the rate of occurrence of failures has changed at a particular point in time.
- Conditional Reliability
vs. Time and Conditional
Unreliability vs. Time shows the reliability or probability
of failure over intervals of time. There are two options:
- Vary Mission Time shows how the reliability or probability of failure would vary over different mission times if the system operated at a specific Start Time. The start time is an assumed value for the system age at the beginning of the mission. For example, a start time = 100 hours means that the origin of the plot corresponds to a system with a total age of 100 hours after a mission of 0 hours. Therefore, an x-axis value of 500 mission hours on that plot would correspond to a system with a total age of 600 hours after a mission of 500 hours.
- Vary Start Time shows how the reliability or probability of failure would vary over different start times if the system operated within a specific Mission Time. The mission time is an assumed value for additional age a system will accumulate during the mission. For example, a mission time = 100 hours means that the origin of the plot corresponds to a system with a total age of 100 hours after a mission of 100 hours. Therefore, an x-axis value of 500 hours on that plot would correspond to a system with a total age of 600 hours after a mission of 100 hours.