Critical spares planning
Prioritize DCS spares by failure consequence, not by price alone.
This case uses a simple weighted matrix to identify modules that deserve on-site stock before a failure turns into a production outage.
Criticality model
Priority score: 4 — LOW
What to record for each module
| Field | Why it matters | Example decision |
|---|---|---|
| Exact catalog number | Prevents ordering a visually similar but incompatible revision. | Photograph front label and rear I/O assembly. |
| Installed quantity | Shows fleet exposure. | One spare may be insufficient across many cabinets. |
| Redundancy role | Separates protected channels from single points. | Prioritize non-redundant interfaces. |
| Firmware / revision | Compatibility can depend on version. | Do not assume a later revision is drop-in. |
| Known-good spare | Inventory is only useful when condition is known. | Record test status and storage location. |
| Lead-time evidence | Turns purchasing uncertainty into a measurable risk. | Review periodically as platforms age. |
Suggested score interpretation
4–6 · Low
Normal procurement planning may be enough. Keep configuration and part data current.
7–9 · Moderate
Review installed quantity, common failure modes and whether one tested spare should be held.
10–12 · High
Treat as a critical spare candidate and document a recovery procedure before failure occurs.
Reusable worksheet
Download DCS critical-spares CSVMaintainer
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