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Updating PLEs in RCM

Updated
  • Updated on Jun 5, 2026
  • Published on Mar 9, 2026
  • 4 minute(s) read
  • JR
  • Tomislav Renic
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This article explains how to manage and update Product Loss Equations (PLEs) used in Analyses.

A PLE determines the economic impacts of stopping a Unit. In RCM, PLE is used to calculate production losses:

  • In the no-maintenance scenario, the PLE contributes to the Price of Non-Conformance (PONC).

  • In the do-maintenance scenario, the PLE contributes to the Price of Conformance (POC), including inspection, maintenance, and replacement activities.

Changes in production margins or throughput may require updating the existing PLEs used in RCM Analyses. In addition, copied RCM Analyses may contain PLEs from another Unit, which can result in incorrect calculations.

PLE update guidelines and frequency

It is recommended to review and update PLEs approximately every four to eight years. More frequent updates are generally considered counterproductive for long-term reliability.

Frequent changes in PLEs may not align with evolving maintenance strategies, such as starting or stopping preventive maintenance tasks. As a result, short-term economic gains from updated PLEs can be offset by later changes in PM strategies.

PLEs that are already in use cannot be modified directly. Instead, create a new PLE and replace the existing one.
PLEs cannot be deleted when they are in use. This is sometimes the case with ‘soft deletes’, where an Analyses is not really removed but only flagged as deleted.

Export for Import

Note

When importing analysis data that includes RSL-originated structures, be aware that changes to PLEs may affect RSL relation links and the RSL revisioning process. In RSL-based analyses, PLE updates often provide limited benefit because RSLs are typically not justified on MEI or detailed cost information.

The recommended method for replacing PLEs is to use the Export for Import functionality in the Analysis grid. After exporting the Analyses, update the PLE references in the Excel file and import the file back into IMS.

Before Updating Multiple PLEs

If the database contains many Units and multiple PLEs per Unit, review the current situation before making updates.

Verify the following:

  • Which PLEs are defined in the Unit and what are the values?

  • Which PLEs are assigned to the Functional Failures in the Systems?

  • Which PLEs are used in the Analyses?

  • What are the MEIs, Criticalities, and Residual Risks before the PLEs are updated?

  • What are the MEI’s, Criticalities, and Residual Risks after the PLEs are updated?

Because PLEs are assigned to Functional Failures within Systems, it is recommended to update PLEs System by System.

Note that Systems can contain Functional Locations (FLOCs) and Equipment from other Units.

List Defined PLEs

Use the Query - PLEs Defined (with Rates and Timing) to review all PLEs defined in the database and see if any need to be updated. To update a PLE, first create a new PLE and then replace the old PLE with the new one.

Caution

When reviewing PLE usage, verify that the PLEs assigned to a Unit are correct and intentionally defined. In some cases, copy-paste or duplicated RCM Analyses may introduce “external” PLEs originating from other Units, which can lead to incorrect economic and risk calculations.

List Used PLEs

Next, use the Query - PLEs Used (with MEI) to identify the PLEs currently used in Analyses. This Query uses the vwRCMData Base view and reports the PLE, FLOC, Equipment, System, Criticality, and MEI.

Decide which PLEs to replace

After creating new PLEs, use the Query - PLEs Used (with MEI) to determine which existing PLEs to replace. Document the planned replacements before performing the update. 

Before replacing PLEs, verify PLEs linked to the various Functional Failures of the Systems. Different Functional Failures within the same System can reference different PLEs.

Use the Query - PLEs Assigned to Functional Failures to review these assignments.

Verify the Effect on Criticalities and MEIs

Replacing PLEs can affect Criticalities and MEIs. To verify the possible effects on Criticalities and MEIs, register the values before and after replacing PLEs. Use the Query - PLEs Used (with MEI) for this comparison.

In addition, changes in POC, PONC, MEI, Criticalities, and Residual Risk should always be compared before and after the update. This comparison provides insight into whether the update delivers meaningful improvements or only shifts economic or risk indicators without long-term benefit.

Update Process

Start the update process from the Systems Main Screen (Overview Grid).

  1. Select the Systems that require updates.

  2. Pin those Systems.

  3. Review the number of related FLOCs, Equipment items, and Analyses highlighted in green.

  1. Switch to the Analysis Main Screen (Overview Grid).

  2. Verify the PLEs shown in the Criticality field.

  1. Export the Analyses using the Export for Import option. The exported file contains the following PLE-related columns:

  • Functional Failure PLE

  • Asset / Detailed / PLE

  • Task: PLE

  1. Update and import the Excel file. For additional information, see Recommended Steps for Updating the Excel File.

Follow these recommendations when preparing the Excel file for import:

  1. Save a copy of the exported file before making changes to ensure you have the original export stored for reference and recovery.

  2. Delete rows where the PLE columns are empty. These rows do not contain PLE data and do not need to be imported.

  3. Check the Unique Task Number column. If a Task Name exists but the Unique Task Number is empty, importing the file will create a new task.

  4. Do not populate empty PLE fields with new values. Leave empty fields unchanged.

  5. Save the updated file.

  6. Before importing, save the current results of the Query - PLEs Used (with MEI) query for comparison.

  7. If the validation step indicates that new objects will be created, cancel the import and review the import file to correct identified issues.

Note

The import process should only update existing data. The import must not create Equipment, Tasks, or Criticalities.

  1. After a successful import run the Query - PLEs Used (with MEI) again. Compare the updated Criticalities and MEI results with the original values to verify if additional updates to the Analyses are required.

  2. Continue with the next System.

Change Logs

To verify and review data imports, go to Settings > Data Transfer > Import History.

The Import History tab displays:

  • all completed imports.

  • individual changes included in each import.

  • the original imported file.

Although this change log applies to all imports, it is especially useful for large-scale PLE updates.