Component Codes vs. Sub-Assets: Downtime, OA, and Reporting

Last updated: November 4, 2026

Overview

Maintenance and reliability teams often want to track individual parts of a machine. L2L offers two ways to do it, Component Codes and Sub-Assets, and they behave differently for downtime and OA.

Component Codes and Component Failure Codes

Question

Answer

Is downtime tracked per Component Code?

No. Downtime is calculated at the machine/sub-asset level, not per Component Code.

Is OA calculated per component?

No. OA uses the machine's downtime minutes only.

Are labor/parts costs summarized by Component Code?

Not out of the box. Labor and parts are tied to the dispatch/machine.

Can I report on Component Codes?

Yes, for failure modes and activity. Use Dispatch History or the Pareto drill-down. This isn't "component-level OA."

What if several components are down at once?

If you log multiple components on one dispatch, downtime counts once for that machine.

Avoid double-counting: Separate, overlapping Down dispatches on the same machine count the same time twice. Best practice is one Down dispatch per actual downtime event.

Sub-Assets

Use Sub-Assets when you need downtime and OA for an individual part of a machine.

  • Can multiple Down dispatches be open on different Sub-Assets of the same machine? Yes. Each Sub-Asset is treated as its own machine for downtime and OA.

  • Create the Down dispatch on the specific Sub-Asset that's down.

  • Don't also create a separate Down dispatch on the parent machine for the same event.

How Sub-Asset downtime affects the parent's OA

Sub-Asset downtime is not split or rolled up as a percentage. That's a key difference from Machine Groups.

  • Machine Groups: Downtime is divided across the group. If 1 of 10 machines is down for 60 minutes, line-level OA counts 6 minutes (60 ÷ 10).

  • Sub-Assets: Downtime counts in full. A Sub-Asset down event is treated like a main machine going down.

Example: A Sub-Asset is down for 11.257 minutes in a 4-hour (240-minute) shift.

  • 240 − 11.257 = 228.743 available minutes

  • 228.743 ÷ 240 = 95.31% OA

Related

  • Component Codes

  • Component Failure Code

  • Downtime Pareto for Action and Components