Performing Lambda Tau Analysis
As described in
Lambda Tau Fault Trees, if a system is well-maintained and routinely undergoes preventative maintenance, the age of specific components may be difficult to determine. From the analyst’s perspective, system components have reached steady state behavior. In such cases, selecting
Lambda Tau as the FTA calculation type is very beneficial.
For this calculation type, lambda represents the failure rate of the system or component. Tau can represent the inspection interval, repair time, or mission time of the system.
To use this calculation type, before you insert any events in the System file, in the properties for this file, you must select Lambda Tau as the FTA calculation type. You can then construct and calculate all of your Lambda Tau fault trees in this particular System file.
1. From the System file, select > . The File Properties window opens.
2. For > , select Lambda Tau.
If this property is unavailable, events have already been inserted in the System file. Unless you delete these events, you cannot change the calculation type.
3. Close the File Properties window.