IR 05000498/2018010
| ML19015A024 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 01/14/2019 |
| From: | James Drake NRC/RGN-IV/DRS/EB-2 |
| To: | Gerry Powell South Texas |
| Drake J | |
| References | |
| IR 2018010 | |
| Download: ML19015A024 (16) | |
Text
ary 14, 2019
SUBJECT:
SOUTH TEXAS PROJECT ELECTRIC GENERATING STATION, UNITS 1 AND 2 - NRC INSPECTION OF TEMPORARY INSTRUCTION 2515/194, INSPECTION REPORT 05000498/2018010 AND 05000499/2018010
Dear Mr. Powell:
On December 6, 2018, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at your South Texas Project Electric Generating Station, Units 1 and 2. The NRC inspectors discussed the results of this inspection with you and other members of your staff.
The results of this inspection are documented in the enclosed report.
The NRC inspectors did not identify any finding or violation of more than minor significance.
This letter, its enclosure, and your response (if any) will be made available for public inspection and copying at http://www.nrc.gov/reading-rm/adams.html and at the NRC Public Document Room in accordance with 10 CFR 2.390, Public Inspections, Exemptions, Requests for Withholding.
Sincerely,
/RA/
James F. Drake, Acting Chief Engineering Branch 2 Division of Reactor Safety Docket Nos. 50-498 and 50-499 License Nos. NPF-76 and NPF-80 Enclosure:
Inspection Report 5000498/2018010 and 05000499/2018010 w/ Attachment: TI 2515/194 Inspection Documentation Request
U.S. NUCLEAR REGULATORY COMMISSION
Inspection Report
Docket Numbers: 05000498, 05000499 License Numbers: NPF-76, NPF-80 Report Numbers: 05000498/2018010, 05000499/2018010 Enterprise Identifier: I-2018-010-0065 Licensee: STP Nuclear Operating Company Facility: South Texas Project Electric Generating Station, Units 1 and 2 Location: Wadsworth, Texas Inspection Dates: December 3, 2018, to December 6, 2018 Inspectors: S. Graves, Senior Reactor Inspector N. Okonkwo, Reactor Inspector Accompanying Personnel: H. Kodali, Electrical Engineer, NRR/DE/EEOB Approved By: James F. Drake, Acting Chief Engineering Branch 2 Division of Reactor Safety Enclosure
SUMMARY
The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting a Temporary Instruction 2515/194, Inspection of the Licensees Implementation of Industry Initiative Associated with the Open Phase Condition Design Vulnerabilities in Electric Power Systems (NRC Bulletin 2012-01),
at South Texas Project Electric Generating Station, Units 1 and 2 in accordance with the Reactor Oversight Process. The Reactor Oversight Process is the NRCs program for overseeing the safe operation of commercial nuclear power reactors. Refer to https://www.nrc.gov/reactors/operating/oversight.html for more information.
List of Findings and Violations No findings were identified.
INSPECTION SCOPES
This inspection was conducted using Temporary Instruction 2515/194 (ADAMS Accession No. ML17137A416), dated October 31, 2017. The inspectors reviewed the licensees implementation of Nuclear Energy Institute voluntary industry initiative in compliance with Commission guidance. The inspectors discussed the impacts of open phase conditions on the licensees electrical system design, the ability to detect and alarm open phase conditions on station transformers, and ongoing implementation of training and updates to operating procedures with plant staff. The inspectors also reviewed licensee analysis and calculations, and performed distribution system and switchyard equipment walkdowns.
OTHER ACTIVITIES
- TEMPORARY INSTRUCTIONS, INFREQUENT AND ABNORMAL Temporary Instruction 2515/194 - Inspection of the Licensees Implementation of Industry Initiative Associated With the Open Phase Condition Design Vulnerabilities in Electric Power Systems (NRC Bulletin 2012-01)
The objective of Temporary Instruction 2515/194 is to verify that licensees have appropriately implemented the Nuclear Energy Institute voluntary industry initiative (ADAMS Accession No. ML15075A454), dated March 16, 2015, including updating their licensing basis to reflect the need to protect against open phase conditions.
Temporary Instruction 2515/194-03.01 - Voluntary Industry Initiative (Part 1)
South Texas Project Electric Generating Station, Units 1 and 2 has concluded that their existing safety-related protective relaying scheme combined with their power transformer configuration provided for detection of, and protection against adverse effects of open phase conditions.
Each Unit at South Texas Project Electric Generating Station normally uses a main generator connected through an output circuit breaker to a combination of two large-capacity main transformers connected in parallel to provide power to offsite circuits, and connected via isolated phase bus ducting to a unit auxiliary transformer to provide power to two of three engineered safety feature busses, trains A and C. The third engineered safety feature bus, train B, is normally powered from a separate standby transformer which is fed from offsite power. When the main generator is offline, the plant loads are typically backfed from the offsite power system via the main transformers through the unit auxiliary transformer. This backfeed power flow occurs automatically upon isolation of the main generator. This capability to immediately backfeed power alleviated the need for fast bus transfer of plant loads to other power sources.
Both the main and unit auxiliary transformers are constructed with shell-type cores and have Wye and Delta connected windings that the licensees analysis shows that when subjected to an open phase condition will regenerate the missing phase voltage. The licensees analysis showed that under both normal and accident loading conditions, and with an open phase condition without ground-fault, the voltage and current values available at the 4.16 kV engineered safety feature busses appeared adequate to support operation. The analysis also showed that in this configuration the negative sequence values, produced by the phase imbalances, would be below five percent and would not have an immediate adverse impact on connected loading. The analysis showed that this configuration, with an open phase and a ground fault condition, would activate the safety-related 4.16 kV bus undervoltage protective relays, isolating two of the three engineered safety feature busses from the faulted source and starting the associated emergency diesel generators.
The standby transformer, also a shell-type core, has Wye connected primary, secondary and tertiary windings, which the licensees analysis showed that when loaded during an open phase condition either with or without a ground fault, would activate the safety-related 4.16 kV bus undervoltage protective relays, isolating the connected engineered safety feature bus from the faulted source and starting the emergency diesel generator. In some analyzed scenarios, the negative sequence voltage exceeded the licensees administrative limit of 4 percent, but the time delays associated with the undervoltage relays (a maximum delay of approximately 55 seconds) were sufficiently short to separate the busses before adversely impacting connected loads.
The licensee used Electrical Power System Analysis and Operation Software (ETAP),version 12.6.5N, to model their electrical transmission and distribution system behaviors under open phase conditions. This simulation software is widely used throughout the industry to model electrical system behavior under transient and steady-state conditions, including analyzing the effects of both single and double open phases on the high side of power transformers. Version 12.6.5N conformed to the licensees quality assurance requirements for 10 CFR Part 50, Appendix B, Quality Assurance Program.
The licensee staff ran several simulations for the inspectors, including a simulation of the 2001 open phase event on Unit 2 described in Licensee Event Report 50-499/2001-001 to compare modeled results to historical information, and ran several scenarios involving failures of isolated phase bus duct conductors without ground faults to ensure the analyzed scenarios were bounding. The inspectors did not identify any discrepancies or errors associated with the software results as compared to the actual event or simulated failures.
INSPECTION RESULTS
- OBSERVATIONS/ASSESSMENT The inspectors identified that under certain electrical system configurations the licensee had not implemented a method to rapidly detect open phase conditions, but due to the capacity of their main transformers this was not an immediate safety concern. The licensee was aware of this issue and entered it into their corrective action program, as Condition Record CR-18-14724.
The licensee also identified that operating on two electrical phases of power was problematic and would not continue to operate in this configuration. The licensee entered this issue into their corrective action program, as Condition Record CR-18-14720 and Condition Record CR-18-14724. The inspectors had reasonable assurance that the licensee would appropriately implement the voluntary industry initiative, with noted changes discussed below.
The inspectors determined that the following activities complied with the Temporary Instruction criteria as written:
Detection, Alarms, and General Criteria TI 2515/194-03.01 - Voluntary Industry Initiative (Part 1)
(1)a. The licensee determined through analysis that open phase conditions will not prevent the functioning of important-to-safety systems, structures, and components.
b. For most analyzed open phase condition scenarios, detection will occur within a reasonably short period of time (e.g., 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />).
c. The licensee was in the process of establishing appropriate documentation regarding open phase condition detection and correction for all plant configurations.
- (2) For open phase conditions on the standby transformers, the analysis showed the safety-related undervoltage relays would actuate, isolating the connected engineered safety feature bus from the faulted source and starting the emergency diesel generators. Also, the licensee established surveillance requirements, every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, to look for evidence of open phase conditions.
- (3) The licensees analysis showed that the existing safety-related undervoltage protective schemes minimized misoperation or spurious action in the range of voltage unbalance normally expected in the transmission system that could cause separation from an operable offsite power source. South Texas Project Electric Generating Station, Units 1 and 2 previously demonstrated that the actuation circuit design for the safety-related undervoltage relays did not result in lower overall plant operation reliability.
- (4) No Class-1E circuits were being replaced with non-Class 1E circuits in the design.
- (5) The licensee provided updates to their Updated Final Safety Analysis Report to include descriptions of the plant susceptibility to open phase conditions and the plant response to these conditions. After discussions with the inspectors the licensee generated Condition Record CR-18-14714 to evaluate additional updates to the Updated Final Safety Analysis Report to include the ability to detect open phase conditions on the high side of the main transformers as described in Licensee Event Report 50-499/2001-001.
Protective Actions Criteria TI 2515/194-03.01 - Voluntary Industry Initiative (Part 1)
- (1) The licensee determined that South Texas Project Electric Generating Station, Units 1 and 2, were susceptible to an open phase condition. South Texas Project Electric Generating Station, Units 1 and 2 considered single open phase conditions (with and without a ground fault) on both the high-voltage side and low-voltage side of the main transformers and standby transformers. Double open phase conditions were also considered in their analysis. All analyzed double open phase conditions resulted in separation of the 4.16 kV engineered safety feature busses from the affected transformer.
- (2) With a single open phase condition present on the standby transformers (with or without ground-fault) and no accident signal present, the analysis showed the safety-related undervoltage relaying scheme would separate the engineered safety feature bus from the faulted transformer and start the emergency diesel generator. Technical specification actions would be met without entry in Technical Specification 3.0.3. Important-to-safety equipment would not be damaged by the open phase condition and shutdown safety would not be compromised. The engineered safety feature busses being powered from the other offsite power sources would not be affected.
With a single open phase condition present on the main transformers (with ground-fault)and no accident signal present, the analysis showed the safety-related undervoltage relaying scheme would separate the engineered safety feature busses from the faulted transformer either immediately or within the time delay period for the undervoltage relays and start the associated emergency diesel generator. Technical specification actions would be met without entry in Technical Specification 3.0.3. The analysis showed that important-to-safety equipment would not be damaged by the open phase condition and shutdown safety would not be compromised. The engineered safety feature busses being powered from the other offsite power sources would not be affected.
- (3) With an open phase condition present on the standby transformers (with or without ground-fault) and an accident signal present, the analysis showed the safety-related undervoltage relaying scheme would separate the engineered safety feature bus from the faulted transformer and start the emergency diesel generator, powering the engineered safety feature loads. Technical specification actions would be met without entry in Technical Specification 3.0.3. Important-to-safety equipment would not be damaged by the open phase condition and shutdown safety would not be compromised. The engineered safety feature busses being powered from the other offsite power sources would not be affected.
With an open phase condition present on the main transformers (with ground-fault) and an accident signal present, the analysis showed the safety-related undervoltage relaying scheme would separate the engineered safety feature busses from the faulted transformer either immediately or within the time delay period for the undervoltage relays and start the emergency diesel generator. Technical specification actions would be met without entry in Technical Specification 3.0.3. The analysis showed that important-to-safety equipment would not be damaged by the open phase condition and shutdown safety would not be compromised. The engineered safety feature busses being powered from the other offsite power sources would not be affected.
- (4) No new periodic tests, calibrations, or setpoint verifications were established as no new protective features were added. The existing surveillance requirements were not modified.
Additional inspections were being considered as part of the licensees corrective action program to identify enhancements related to transformer inspections and walkdowns.
These activities were captured in Condition Record CR-18-14720.
No findings were identified.
The inspectors identified the following exceptions to the Temporary Instruction criteria based on the licensees decision to use the existing infrastructure to provide detection and protection for open phase conditions, and their efforts to identify a method to detect open phase conditions in all configurations:
Detection, Alarms, and General Criteria Exceptions TI 2515/194-03.01 - Voluntary Industry Initiative (Part 1)
- (1) The licensees design did not have specific detection or alarms for an open phase condition in the control room. For plant configurations in which the main generator is providing power to plant loads through the unit auxiliary transformer, the licensee relied, in part, on demonstrated motor current unbalance and protective relay response on the 13.8 kV busses to identify impacts from an open phase condition. This immediate plant response alerts the licensee to the possible presence of an open phase condition in this configuration.
To improve the reliability of this detection capability, the licensee entered this issue into their corrective action program as Condition Record CR-18-14720 which will evaluate ways to enhance response to an open phase condition, including changes to operating procedures to incorporate open phase condition diagnostics, crew recognition of open phase conditions, and detailed crew response to minimize the effects of open phase conditions. Specifically, the condition record included provisions to:
a. Incorporate monitoring all 3 phases of 13.8 kV and 4.16 kV busses with criteria for quickly diagnosing open phase conditions b. Identify training requirements to enhance Operator recognition of open phase conditions and responses c. Include all enhancements into repeatable processes to ensure consistent crew recognition and response
- (2) For configurations in which plant loads are being powered from the offsite power supply through the main transformers and the unit auxiliary transformer (backfeed condition), for open phase conditions without a ground fault, the use of current unbalance protective relaying (automatic detection) did not appear to be an effective method of detection, in part, because of the limited loading on the 13.8 kV busses in this configuration (i.e. no large motors running so no current unbalance protection relays would be expected to operate) and because the analysis showed adequate voltages at the 4.16 kV engineered safety feature busses to preclude actuation of the safety-related undervoltage relays. The licensee recognized that this two-phase electrical power condition did not meet the original design configuration of a three-phase electric power system. The licensee entered this issue into their corrective action program as Condition Record CR-18-14724 to evaluate the need to analyze and detect for open phase conditions when the main transformer is in a backfeed configuration. This evaluation is expected to identify methods of open phase detection in this operating configuration within a reasonably short period of time (e.g. 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or less).
Protective Actions Criteria Exceptions TI 2515/194-03.01 - Voluntary Industry Initiative (Part 1)
- (1) With a single open phase condition present on the main transformers without ground-fault and an accident signal present, the licensees analysis showed that the voltage and current values available at the 4.16 kV engineered safety feature busses were adequate to support operation, will all LOCA loading running on the engineered safety feature busses and no emergency diesels running. The analysis also showed that in this configuration the negative sequence values, produced by the phase imbalances, would be below the licensees administrative limit of five percent and therefore would not have an immediate adverse impact on connected loading. The inspectors noted that the modeling software used nominal nameplate values for analyzed plant equipment such as induction motors and transformers, which typically does not consider any age-related degradations or other potential latent issues affecting operating margin. Further, the licensee recognized that this two-phase electrical configuration differs from the original analyzed design of three-phase electrical power systems, and explained to the inspectors that they had no plans to operate with an existing open phase condition, even though their analysis showed this was feasible. The licensee entered this issue into their corrective action program as Condition Record CR-18-14720 and Condition Record CR-18-14724 to evaluate the need to analyze and detect open phase conditions when the main transformer was in a backfeed condition.
EXIT MEETINGS AND DEBRIEFS
On December 6, 2018, the inspectors presented the temporary instruction inspection results to Mr. G. Powell, President and Chief Executive Officer, and other members of the licensee staff.
The inspectors verified no proprietary information was retained or documented in this report.
DOCUMENTS REVIEWED
Temporary Instruction 2515/194 - Inspection of the Licensees Implementation of Industry
Initiative Associated with the Open Phase Condition Design Vulnerabilities in Electric Power
Systems (NRC Bulletin 2012-01)
Condition Records
18-14634* 18-14724* 18-14707* 18-14720* 18-14634*
18-14709* 18-14714* 12-8728 95-1747
Note: *Identifies condition records written during the inspection
Procedures
Number Title Revision
0POP01-ZQ-0022 Plant Operations Shift Routines 80
(Pages 20-25)
0POP09-AN-03M3 Annunciator Lampbox 3M03 Response Instructions 34
0POP04-AE-0001 First Response to Loss of any or all 13.8 kV or 4.16 kV Bus 44
OPSP06-PK-0006 4.16KV Class 1E Degraded Voltage Relay-Channel 31
Calibration/TADOT-Channel 2
7Z311Z47503 Main Annunciator Window Assignment List 19
Drawings
Number Title Revision
00000E0AAAA, Sh. Single Line Diagram Main One Line Diagram 29
Unit No. 1 & 2
00009E0PK04#1, Elementary Diagram ESF Transformer & 4.16kV Bus E1A, 14
Sh. 01 E1B & E1C Protection & Metering
Figure 8.2-3 High Voltage Switchyard Single Line Diagram 19
0E0AAAA, Sh. 1 Single Line Diagram Main One Line Diagram 29
Unit No. 1 & 2
09ENN05#1, Sh.1 Elementary Diagram Main Generator Breaker Control and 8
Protection
00009E0NN05#1, Elementary Diagram Main Generator Breaker Protection 8
Sh. 2 and Control
00009E0PK04#1, Elementary Diagram ESF Transformer & 4.16KV Bus 14
Sh. 2 E1A, E1B, & E1C Protection and Metering
00009E0PKB#1, Single Line Diagram 4.16 KV Class 1E Switchgear 14
Sh. 1
9-E-PKAA-01, #2. Single Line Diagram 4.16 KV Class 1E Switchgear 10
Drawings
Number Title Revision
9-E-PKAA-01, #1. Single Line Diagram 4.16 KV Class 1E Switchgear 12
00009E0PK04#2, Elementary Diagram ESF Transformer & 4.16KV Bus 14
Sh. 2 E2A, E2B, & E2C Protection and Metering
00009E0PKAB#2, Single Line Diagram 4.16 KV Class 1E Switchgear E2B 10
Sh. 1
9-E-PKAC-01#1, Single Line Diagram 4.16 KV Class 1E Switchgear E1C 13
9-E-PKAC-01 #2 Single Line Diagram 4.16 KV Class 1E Switchgear E2C 9
030-505-500-20, South Texas Substation One-line Relay and Metering 38
Sh. 1 Scheme
030-505-500-20, South Texas Substation One-line Relay and Metering 26
Sh. 2 Scheme
B05595-00002R2 Outline Dimensions A
Miscellaneous Revision
Documents Number Title or Date
1OOI01-OL-0010 Unit 1 CP Days Logsheet December 3, 2018
2OOI01-OL-0010 Unit 2 CP Days Logsheet December 3, 2018
1OOI01-OL-0003 Unit 1 Yard Days Logsheet December 2, 2018
LOR 165.01.LP.01 Operator Training Presentation - 1
13.8kv 13.8 & 4.16 KV Electrical Distribution
100.20.HO.01 Operator Training Student Handout - Offsite 11
Electrical Distribution
LOR 133 Operator Training - Plant Events
NLO100.20.HO.01 Offsite Electrical Distribution Student Handout 11
NOC-AE-01001075 South Texas Project Electric Generating Station, April 23, 2001
Unit 2, Docket No. STN 50-499, Licensee Event
Report 01-002 Manual Reactor Trip
NOC-AE-12002917 South Texas Project Electric Generating Station, October 25, 2012
Response to NRC Bulletin 2012-01: Design
Vulnerability in Electrical Power System
NOC- AE-14003077 STP Nuclear Operating Company Response to January 30, 2014.
Request for Additional Information Response to
Bulletin 2012-01, Design Vulnerability in Electrical
Power System
Miscellaneous Revision
Documents Number Title or Date
N.Y.20-118 Generator Circuit Breaker Pole Outline PKG2C May 12, 1984
X-DGM-816 Flow Diagram 2-HBC-10 Air Compressor Plant July 12, 1984
General Arrangement
South Texas Project Electric Generating Station, December 3, 2018
Units 1 and 2 Open Phase Condition (OPC)
Protection Presentation
Vendor Documents Revision
Number Title or Date
Westinghouse - Report of Transformer Test, April 26, 1978
Serial No. BBM1376 (Standby Transformer)
1ZXX294309001-PM6 ABB - Rating Plate (Main Transformer) September 22, 2016
B05595-00002R2 Outline Dimensions (Main Transformer) March 24, 2017
VTD-G080-0061 GEK-65583, Type IJC51E Current Balance 0
Relay
Calculations
Number Title Revision
14-PK-007 Open Phase Analysis for the Standby and Main Power 1
Transformers
EC5000 Voltage Regulation Study 8
EC5052 Degraded and Under-voltage Protection and 6
20/208 VAC Panelboard Voltage Analysis
EC5002 Electrical Auxiliary Power Distribution System Model 8
TI 2515/194 Inspection Documentation Request
South Texas Project Electric Generating Station
Please provide the following documentation (Items 1 - 8) to the lead inspector prior to the onsite
inspection date, preferably no later than November 5, 2018. Whenever practical, please provide
copies electronically (IMS/CERTREC is preferred). Please provide an index of the requested
documents which includes a brief description of the document and the numerical heading
associated with the request (i.e., where it can be found in the list of documents requested).
Sam Graves, Lead Inspector
RIV/DRS/EB2
1600 E. Lamar Blvd.
Arlington, TX 76011
817-200-1102
samuel.graves@nrc.gov
1. Copies of any calculations, analyses, and/or test reports performed to support the
implementation of your open phase condition (OPC) solution or design. If, in your
implementation, OPCs are not detected and alarmed in the control room include
documentation that:
a. Demonstrates the OPC will not prevent functioning of important-to-safety systems,
structures and components (SSCs); AND
b. Detection of an OPC will occur within a short period of time (e.g., 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />) AND
c. Establishes shiftly surveillance requirements to look for evidence of OPCs.
2. If your calculational basis or analysis has determined there is no single credible failure that
could cause an OPC, then provide the engineering evaluation(s) which document the
technical basis for this determination. The Bruce Power and Forsmark operating experience
must be considered as part of this analysis. Also, provide details on any testing performed
to validate the analytical results.
3. Copies of any modification packages, including 10 CFR 50.59 evaluations if performed,
used for or planned for the implementation of your OPC solution.
4. Copies of periodic maintenance, surveillance, setpoint calibration, and/or test procedures
implemented or planned, for your OPC solution or design. If not complete, provide
documentation showing plans to complete. Also, provide documents showing the
surveillance requirements have been added to the plant TSs if necessary to meet the
provisions of 10 CFR 50.36.
5. Copies of your licensing basis changes to Updated Final Safety Analysis Report (UFSAR)
and/or Technical Specifications (TS), as applicable, which discuss the design features and
analyses related to the effects of, and protection for, any open phase condition design
vulnerability. If these documents have not been updated, provide documentation of your
plans to do so.
6. Copies of any procurement specifications and acceptance testing documents related to the
installation of your OPC solution or design.
7. Copies of any site training the team will need to accomplish to gain access to areas with, or
planned, major electrical equipment used in your OPC solution (i.e. switchyard).
8. If your solution does not identify open phase conditions for all credited electrical loading
conditions (heavy, light, and unloaded) please provide documentation that demonstrates
OPCs will be automatically detected as soon as loads are transferred to the standby source.
9. Provide documentation showing that with an OPC occurrence and no accident condition
signal present, either:
a. An OPC does not adversely affect the function of important-to-safety SSCs, OR
b. TS LCOs are maintained or the TS actions are met without entry into TS LCO 3.0.3 (or
equivalent) AND
i. Important-to-safety equipment is not damaged by the OPC, AND
ii. Shutdown safety is not compromised
10. With OPC occurrence and an accident condition signal present:
a. Provide documentation showing that automatic detection and actuation will transfer
loads required to mitigate postulated accidents to an alternate source and ensure that
safety functions are preserved, as required by the current licensing bases, OR
b. Provide documentation showing that all design basis accident acceptance criteria are
met with the OPC, given other plant design features. Accident assumptions must include
licensing provisions associated with single failures. Typically, licensing bases will not
permit consideration of the OPC as the single failure since this failure is in a non-safety
system.
Please provide the following documentation to the team on the first onsite day. Whenever
practical, please provide copies electronically, except for drawings. Drawings should be
provided as paper copies of sufficient size (ANSI C or D) such that all details are legible.
11. A brief presentation describing your electric power system design and typical electrical
transmission and distribution system alignments; OPC design schemes installed to detect,
alarm and actuate; bus transfer schemes; and maintenance and surveillance requirements.
2. Plant layout and equipment drawings for areas that identify: (a) the physical plant locations
of major electrical equipment used in your open phase condition solution; (b) the locations of
detection and indication equipment used in the open phase condition sensing circuits.
Electrical drawings showing interfaces between your open phase condition solution and
plant equipment, including the main one-line diagram(s).
13. If OPC actuation circuits are required, provide documentation that demonstrates continued
coordination with the other protective devices in both the offsite electrical system and the
onsite electrical system
14. Access to locations in which open phase condition equipment is installed or planned (i.e.
switchyard, transformer yard, etc.)
15. Copies of documentation or testing that demonstrates your OPC solution minimizes spurious
actuation or misoperation in the range of voltage imbalance normally expected in the
transmission system that could cause undesired separation from an operable offsite power
source.
This document does not contain new or amended information collection requirements
subject to the Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.). Existing
information collection requirements were approved by the Office of Management and
Budget, Control Number 31500011. The NRC may not conduct or sponsor, and a person
is not required to respond to, a request for information or an information collection
requirement unless the requesting document displays a currently valid Office of
Management and Budget control number.
This document will be made available for public inspection and copying at
http://www.nrc.gov/reading-rm/adams.html and at the NRC Public document Room in
accordance with 10 CFR 2.390, Public Inspections, Exemptions, Requests for
Withholding.
SUNSI Review: ADAMS: Non-Publicly Available Non-Sensitive Keyword: NRC-002
By: STG Yes No Publicly Available Sensitive
OFFICE SRI:EB2 RI:EB2 C:EB2 C:RPBB C:EB2
NAME SGraves NOkonkwo JDrake NTaylor JDrake
SIGNATURE /RA/ /RA-e/ /RA JMM for/ /RA/ /RA/
DATE 12/28/2018 12/18/2018 12/28/2018 1/11/2019 1/14/2019