Modules · Event analysis · Module 079
PRC-004-6 Misoperation Identification and Correction
Every relay trip at your plant screened for a possible Misoperation, the 120-day determination clock started, and the investigation and corrective action plan tracked to closure.
About this module
What this module covers.
PRC-004-6 requires each Transmission Owner, Generator Owner, and Distribution Provider that owns a Bulk Electric System (BES) interrupting device that operated to identify, within 120 calendar days of the operation, whether its Protection System component or components caused a Misoperation (R1); to notify the other owner or owners of a shared Composite Protection System within the same 120 calendar days (R2); to identify, when notified, whether its own components caused a Misoperation (R3); within 120 calendar days of first identifying a Misoperation, to identify its cause or carry an investigation plan until the cause is found (R4); within 60 calendar days of first identifying a cause, to develop a Corrective Action Plan (CAP) and evaluate its applicability to the entity's other Protection Systems, or explain in a declaration why corrective actions are beyond the entity's control (R5); and to implement each CAP, updating it if actions or timetables change, until completed (R6).
This module screens every relay event record from your plant for a Protection System operation, starts the 120-day clock for the devices you own, and carries each operation through determination, notification, cause, and CAP in one workflow. It also covers development of your compliance procedure and support for each investigation.
Module: 079
Kind: Event analysis
Governing body: NERC
Applies to: Operating plants
Typical time: Days per event, not weeks
Dashboard capabilities
- Every relay event record from your plant that shows a trip is screened under R1: the relay is matched to your plant profile by its identifier, and the owner of the breaker it trips decides what you owe.
- For a breaker you own, the R1 determination date (120 days from the trigger) is set and tracked as a task; for a jointly owned breaker, the R2 notification to the other owner is due the same day; for a Transmission Owner's breaker, you are reminded that your R3 duty starts when the Transmission Owner notifies you.
- A relay that is not in your plant profile, or a breaker with no recorded owner, is flagged with the missing mapping so you can fix it; supervisory control and data acquisition (SCADA) records and relay records with no trip are set aside with the reason.
- From the event you open the PRC-004-6 Misoperation investigation workflow with the record summary already filled in, and record the R1 determination (the device that operated and its owner, whether it was a Protection System operation, and the Misoperation category: Failure to Trip, Slow Trip, or Unnecessary Trip, each During Fault or Other Than Fault; Not a Misoperation; or Undetermined) and the log of R2 and R3 notifications sent and received.
- Identifying the cause sets the 60-day R5 deadline as a task; you record the CAP or the declaration, assess its applicability to your other plants, and track CAP status and milestones under R6 until completed.
- You receive a final report listing the determination, the category, the notifications, and the CAP.
Support services
What GridStrong does inside this module.
Task 1: Develop Compliance Procedure
- Create an audit-ready compliance procedure for meeting the PRC-004-6 requirements, working collaboratively across your engineering, operations, and compliance departments. This includes:
- Identifying applicable assets, functions, subject matter experts (SMEs), roles, responsibilities, and ownership
- Determining specific actions and evidence to demonstrate compliance with specific requirements and measures
- Conducting a gap analysis comparing current practices with the standard's requirements, identifying missing processes, incomplete documentation, any staff training needed, etc.
- Developing clear step-by-step procedures for PRC-004-6 that align with your internal controls and documentation policies, including Misoperation identification, classification, notification, root-cause analysis, and CAP development
- Establishing compliance timelines that align with the standard's deadlines (120-day identification and notification, 120-day cause determination, 60-day CAP)
- Defining specific compliance evidence per site
Task 2: Misoperation Investigation (for each Protection System operation)
- Review the event records, relay settings, and Protection System documentation for the operation
- Determine whether the operation was a Misoperation and classify it
- Identify the notifications owed to or received from other Protection System owners
- Determine the cause within the 120-day R4 window, or document the investigation plan, and propose corrective actions, or document why corrective actions are beyond your control
- Evaluate the applicability of the CAP to your other Protection Systems and locations
Final deliverables
- Task 1: Compliance procedure for PRC-004-6.
- Task 2: Misoperation investigation report for each Protection System operation, documenting the determination, the Misoperation category, notifications, cause, and the CAP or declaration.
What we need from you
- Relay event records for each BES interrupting device operation, as Common Format for Transient Data Exchange (COMTRADE) records or Schweitzer Engineering Laboratories (SEL) event reports.
- Plant profile relays with their identifiers, the breakers each relay trips, and each breaker's ownership (Plant, Transmission Owner, or Joint).
- Protection System documentation (relay models, settings, communication schemes, direct current (DC) supply, control circuitry).
- Operator logs, notifications received from other owners, and any existing CAPs.
Assumptions and considerations
How the scope is bounded.
- You supply all event records and site-specific documentation needed for each investigation.
- Breaker ownership recorded in your plant profile is accurate; records whose relay does not match the profile are flagged for review, not assessed.
- The screen identifies operations for review; the Misoperation determination is made by the reviewing engineer.
- Data is assumed to be time synchronized or to carry accurate time stamps across data sources.
- We do not assume liability for any data or information you supply that is inaccurate or incorrect.
Other modules
Every module runs on the same record.
Run this module on one site.
Tell us the plant and the deadline. An engineer confirms the inputs, the schedule and what the Dashboard needs from you.