Audit-ready, every day.

The core principle

Maintenance only counts if you can evidence it.

PRC-005-6 requires every Generator Owner, Transmission Owner, and Distribution Provider on the Bulk Electric System to run a documented Protection System Maintenance Program — and to produce dated records proving each activity happened inside its maximum interval. NERC leaves the how to the utility; the evidence is what gets audited.

Where PRC-005-6 sits

FERC delegates to NERC, which delegates monitoring to six Regional Entities. Protection & Control (PRC) is one of fourteen mandatory Standards subject to enforcement — PRC-005-6 is one of twenty within it, and it is the one that governs Protection System maintenance.

What falls under it

All three functional entities carry the same R1–R5 obligations. The scope splits into three families of Components — every discrete piece of equipment inside them needs a maintenance record.

A maintenance program for a Component is one or more of these five activities:

Building a PSMP that holds up under audit

Five requirements, each with a matching measure that defines the evidence you must be able to hand an auditor.

1. 1

   R1 — Establish the program

   Declare a maintenance method for every Component Type — time-based, performance-based, or a combination — and state which monitoring attributes you rely on to extend intervals.

   M1 evidence: the current dated PSMP, plus documentation of the method applied to each Component Type.

2. 2

   R2 — Justify performance-based intervals

   If any interval is performance-based, follow the procedure in PRC-005-6 Attachment A to establish and maintain it.

   M2 evidence: Component lists, dated maintenance records, and dated analysis records and results.

3. 3

   R3 — Hold the time-based intervals

   Perform at least the minimum activities within the maximum intervals set by Tables 1-1 through 1-5, Table 2, Table 3, Tables 4-1 through 4-3, and Table 5.

   M3 evidence: dated maintenance records, summaries, check-off lists, inspection records, or work orders.

4. 4

   R4 — Implement the performance-based program

   Actually run the program you justified under R2, for every Component inside it.

   M4 evidence: the same dated records as R3, covering the performance-based population.

5. 5

   R5 — Chase down unresolved issues

   A deficiency that can't be corrected inside the maintenance interval becomes an Unresolved Maintenance Issue — and you must show continuing effort to close it. M5 evidence can include:

   • Corrective work orders
   • Replacement Component orders and invoices
   • Budget approval requests and approvals
   • Project schedules with completed milestones
   • Return material authorizations and purchase orders

Worked example — choosing a maintenance method

The core principle

A facility is only as strong as its most limiting element.

FAC-008-3 requires every Transmission Owner and Generator Owner to rate a facility by its weakest component — not its average, not its newest part. Under the current version you also identify the next most limiting element and account for impaired equipment as an operating limit.

Where FAC-008-3 sits

FERC delegates to NERC, which delegates monitoring to six Regional Entities. The Transmission & Generator Owners running the grid answer to whichever standards apply — FAC-008-3 governs Facility Ratings.

What it requires

Normal and Emergency ratings must respect the most limiting equipment. Where the documentation obligation falls depends on who owns what.

Building an FRM that holds up under audit

1. 1

   Document ambient conditions

   Every element needs an FRM entry showing how ambient conditions were considered — matching the actual region the facility operates in.

2. 2

   Split ratings by season, if conditions vary

   Keep separate summer and winter rating sets — each with its own Normal and Emergency rating.

3. 3

   Ground it in a technical foundation

   Every rating needs a paper trail:

   • Manufacturer rating for each element
   • Nameplate photos
   • Calculations used to determine element ratings
   • Applicable industry ratings
   • Engineering drawings
4. 4

   Maintain the rating chain per facility

   Identify each element's rating, then the most- and next-most-limiting element as seen by each owner — and the overall pair that sets the facility's Normal and Emergency ratings.

Worked example — a single facility