Defining Failure Modes

By default, when a new reliability element is created, a simple, unrepaired exponential failure mode is available (and it is assumed that this failure mode causes the component to stop operating when it occurs).

Note, however, that this is a very simple way to model failure (and therefore should be used with caution). An unrepaired, exponential failure (with a constant hazard rate) may be appropriate for random (and typically externally-generated) failures, but is not likely to be appropriate for failure due to processes such as wear and tear. Moreover, failure modes do not necessarily have to be fatal.

Fortunately, one of the Reliability Module's greatest strengths is its ability to represent failure modes in great detail. This is done by clearing the Use simple failure rate instead of failure modes checkbox:

When you do this, the Failure Rate input field is removed and replaced with a hyperlink:

In addition, a Failure Modes tab is added to the dialog. Clicking on the tab or the hyperlink shown above displays the Failure Modes tab, which provides access to the Reliability Module's advanced failure mode features.

These advanced features are discussed in detail in the topics below.