The Telcordia Issue 4, Issue 3, and Issue 2 models calculate mean failure rates for parts and assemblies.

For each part, the mean failure rate is calculated using all of the Pi factors, which come from tables and formulas specified in the standard. In the Prediction module, you click Pi Factor in the part’s Prediction Data pane to view the mean failure rate for a quantity of 1. For more information, see Part Pi Factors.

You can use the Format Builder to insert fields such as Failure Rate, Unit and Failure Rate, Mean in the System Tree Items table or Parts Table. Failure Rate, Unit displays the mean failure rate for a quantity of 1. Failure Rate, Mean takes the quantity into consideration. Additionally, you can also use the Format Builder to insert Pi Factors. This field contains all Pi factor values for calculating the part’s failure rate.

For each assembly, Failure Rate, Mean displays the summation of Failure Rate, Mean values for all child parts.