	Related Topics:
	FMEA Records

Causes (Failure Modes)

To add a cause (typically called a failure mode in RCM analysis) to the FMEA, select the effect with which it is associated and choose FMEA > FMEA Records > Causes.

Note: If the FMEA structure for the hierarchy is Causes Before Effects, you would select the failure with which the cause is associated and then choose FMEA > FMEA Records > Causes.

To insert a new cause above the selected cause, FMEA > FMEA Records > Causes > Insert Cause.

To edit an existing cause in the project, either edit it directly in the worksheet view or use the properties window. To open the properties window, select the cause and choose FMEA > FMEA Records > Causes > Edit Cause or double-click the cause in the hierarchy or filtered view.

Cause Properties Window

When adding a cause, in addition to the options common to all FMEA record properties windows, you will need to define the cause properties.

Note: The fields that are enabled in the interface and the options available in configurable drop-down lists will depend on the interface style settings that have been defined for the current project. You can choose Project > Management > Configurable Settings > Interface Style to open the Edit Interface Style (This Project) window and change the settings for the current project.

In the Cause area the following fields may be available:

Cause Description: The potential cause(s) for each failure. This should be the actionable level of the analysis, which is the level of causation at which corrective actions and/or controls could be applied effectively.
Short Description: A shortened (50 character maximum) version of the record description that appears in diagrams where the full description would be too long to display. If you do not enter text in this field, the software automatically populates the field when you save the record (based on the first 50 characters of the record description). Note that the description fields are not automatically updated if you later change one of them so you must be sure to make the same changes to both fields if necessary.
Detection Method: The mechanisms that are in place to detect the failure cause.
Compensating Provisions: The mechanisms that are in place to compensate if the failure cause occurs.
Classification: Used to identify design characteristics that require special manufacturing control (e.g., Critical, Significant, Key Leading, etc). The available options will be determined based on the interface style defined for the project.
Initial Occurrence and Revised Occurrence: Numerical ratings that estimate the probability of occurrence for the potential failure cause. The options in these drop-down lists are based on the occurrence scale that has been assigned in the Project Properties window. The revised occurrence rating is based on the assumption that all recommended actions for the cause have been performed.
Initial Detection and Revised Detection: Numerical ratings that estimate the probability that the problem will be detected before it reaches the customer or end user. The options in these drop-down lists are based on the detection scale that has been assigned in the Project Properties window. The revised detection rating is based on the assumption that all recommended actions for the cause have been performed.

Tip: If you need to define the reliability/maintainability characteristics for this record, use the FMRA tab. These characteristics will be applicable if you wish to perform criticality analysis, use the FMEA occurrence ratings to calculate a preliminary baseline estimate of the system reliability, share system configuration/reliability data between RCM++ and BlockSim or perform RCM cost/availability calculations.

What's Changed? In previous versions of RCM++, the probability and corrective maintenance information for the cause (failure mode) were set using the Probability of Occurrence and Corrective Maintenance pages of the Cause Properties window. In Version 8, the probability of occurrence and the tasks for the cause are defined by setting the cause's universal reliability definition (URD) in the new FMRA tab.