I recently started using 217Plus model in Windchill QS and trying to understand how various factor affect the base failure rate from the tutorial at http://www.theriac.org/DeskReference/printDocument.php?id=233.
In Section 3, the system reliability model has a pi factor for environment (Temperature delta, Vibration).
One question I have is, why do we need environmental factor modifier at system level when it is already considered in the component model. If we do need it at system level, why is it independent of the cycling rate – considering it is dependent on temperature delta and not absolute temperature.
I would appreciate it if anyone can throw light on this. Thank you.