Streamlining Maintenance with Fiix's Nested PM: One Schedule, Multiple Tasks

The Traditional Approach to Preventive Maintenance

Historically, if several PM cycles for a piece of equipment overlapped on the same date, CMMS users had to create separate scheduled maintenance triggers for each cycle. For example, a monthly oil change paired with an annual oil and filter change would generate two distinct work orders on the same day, inflating paperwork and administrative overhead. This method works when you manage a handful of assets, but quickly becomes unwieldy as the asset portfolio grows.

Introducing Nested PM – One Task List, Multiple Cycles

Fiix is proud to unveil our Nested PM feature, designed to consolidate PMs of varying lengths and complexities into a single, coherent schedule. By nesting PMs, you only need to maintain one master PM. The Nested PM system dynamically releases the appropriate tasks to the work order based on the specific cycle that is due.

Using the monthly/annual example, the monthly and annual PMs can be bundled together. When the monthly PM is due, the Nested PM will publish only the monthly tasks; when the annual PM is due, both the monthly and annual tasks are released.

Nested PM logic assumes that higher‑frequency tasks are embedded within lower‑frequency cycles. For instance, all monthly tasks automatically appear in each annual PM.

How Nested PMs Operate

During setup, each PM activity is assigned a multiplier relative to the shortest cycle. Consider a time‑based example where the weekly PM is the shortest interval and serves as the Root PM (N1). With 52 weeks in a year, the annual PM carries a multiplier of 52.

In a meter‑based scenario, the logic is identical. The 250‑hour PM acts as the root (N1), and subsequent PMs are multiples of that base interval.

Practical Time‑Based Example

Suppose an asset follows these cycles:

The nesting diagram is shown below, and during an annual PM you execute the full suite of weekly, monthly, quarterly tasks, plus the annual add‑ons.

Task manager view during the annual PM:

Accessing Nested PM in Your CMMS

Nested PM is included in the Enterprise package of Fiix CMMS. Existing Enterprise users will see a dedicated "Nested PM" tab when creating scheduled maintenance. If you are on a non‑enterprise tier, simply click the green upgrade button within your CMMS to unlock Nested PM and other advanced features such as rotating assets, report writer, multi‑site support, and our API.

Key Considerations

1. Follow the 10% rule: set the due date to 10% of the root cycle to avoid lateness in higher‑frequency PMs.
2. When intervals don’t align (e.g., a weekly PM every 7 days vs. a monthly PM on the 1st), adjust the monthly interval to 28 days to synchronize schedules.

Additional documentation and FAQs are available in the help desk section.