ML18291A628
| ML18291A628 | |
| Person / Time | |
|---|---|
| Site: | Brunswick  |
| Issue date: | 10/18/2018 |
| From: | William Gideon Duke Energy Progress |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| RA-18-0148 | |
| Download: ML18291A628 (55) | |
Text
William R. Gideon Vice President Brunswick Nuclear Plant P.O. Box 10429 Southport, NC 28461 o: 910.832.3698 October 18, 2018 Serial: RA-18-0148 10 CFR 50.90 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001
Subject:
Brunswick Steam Electric Plant, Unit Nos. 1 and 2 Renewed Facility Operating License Nos. DPR-71 and DPR-62 Docket Nos. 50-325 and 50-324 Request for License Amendment - Technical Specification 3.3.8.1, Loss of Power (LOP) Instrumentation Ladies and Gentlemen:
Pursuant to 10 CFR 50.90, Duke Energy Progress, LLC (Duke Energy), is requesting an amendment associated with Technical Specification (TS) 3.3.8.1, Loss of Power (LOP)
Instrumentation, for the Brunswick Steam Electric Plant (BSEP), Unit Nos. 1 and 2. The proposed change revises the Allowable Value associated with Function 1.b, (i.e., 4.16 kV Emergency Bus Undervoltage (Loss of Voltage) - Time Delay) of Table 3.3.8.1-1, Loss of Power Instrumentation.
The enclosure provides a description and assessment of the proposed change. Attachments 1 and 2 to the enclosure provide the existing TS pages, for Units 1 and 2, respectively, marked to show the proposed change. Attachments 3 and 4 provide revised (i.e., typed) TS pages for Units 1 and 2, respectively. Attachment 5 provides BSEP Calculation 04KV-0001, 4.16 kV Emergency Bus (Loss of Voltage) Undervoltage and Time Delay Uncertainty and Setpoint Calculation (For 4kV 1-E1(E2)-AE7(AG5)-27/59E and 2-E3(E4)-AI3(AK0)-27/59E); which establishes the revised Allowable Value.
Approval of the proposed amendment is requested within one year of completion of the NRCs acceptance review. Once approved, the amendment shall be implemented prior to the end of the 2023 Unit 2 refueling outage.
In accordance with 10 CFR 50.91, Duke Energy is providing a copy of the proposed license amendment to the designated representative for the State of North Carolina.
This document contains no new regulatory commitments. Please refer any questions regarding this submittal to Mr. Lee Grzeck, Manager - Regulatory Affairs, at (910) 832-2487.
U.S. Nuclear Regulatory Commission Page 2 of 3 I declare, under penalty of perjury, that the foregoing is true and correct. Executed on October 18, 2018.
Sincerely,
~
William R. Gideon MAT/mat
Enclosure:
Description and Assessment of the Proposed Change : Proposed Technical Specification Changes (Mark-Up) - Unit 1 : Proposed Technical Specification Changes (Mark-Up) - Unit 2 : Revised (Typed) Technical Specification Pages - Unit 1 : Revised (Typed) Technical Specification Pages - Unit 2 : Calculation 04KV-0001, 4.16 kV Emergency Bus (Loss of Voltage)
Undervoltage and Time Delay Uncertainty and Setpoint Calculation (For 4kV 1-E1 (E2)-AE7(AG5)-27/59E and 2-E3(E4)-Al3(AK0)-27/59E)
U.S. Nuclear Regulatory Commission Page 3 of 3 cc:
U. S. Nuclear Regulatory Commission, Region II ATTN: Ms. Catherine Haney, Regional Administrator 245 Peachtree Center Ave, NE, Suite 1200 Atlanta, GA 30303-1257 U.S. Nuclear Regulatory Commission ATTN: Mr. Dennis J. Galvin 11555 Rockville Pike Rockville, MD 20852-2738 U. S. Nuclear Regulatory Commission ATTN: Mr. Gale Smith, NRC Senior Resident Inspector 8470 River Road Southport, NC 28461-8869 Chair - North Carolina Utilities Commission (Electronic Copy Only) 4325 Mail Service Center Raleigh, NC 27699-4300 swatson@ncuc.net Mr. W. Lee Cox, III, Section Chief (Electronic Copy Only)
Radiation Protection Section North Carolina Department of Health and Human Services 1645 Mail Service Center Raleigh, NC 27699-1645 lee.cox@dhhs.nc.gov
RA-18-0148 Enclosure Page 1 of 7 Description and Assessment of the Proposed Change
Subject:
Request for License Amendment - Technical Specification 3.3.8.1, Loss of Power (LOP) Instrumentation
- 1.
SUMMARY
DESCRIPTION
- 2.
DETAILED DESCRIPTION 2.1 System Design and Operation 2.2 Current Technical Specification Requirements 2.3 Reason for the Proposed Change 2.4 Description of the Proposed Change
- 3.
TECHNICAL EVALUATION
- 4.
REGULATORY EVALUATION 4.1 Applicable Regulatory Requirements/Criteria 4.2 No Significant Hazards Consideration Determination Analysis 4.3 Conclusions
- 5.
ENVIRONMENTAL CONSIDERATION
- 6.
REFERENCES ATTACHMENTS:
- 1.
Proposed Technical Specification Changes (Mark-Up) - Unit 1
- 2.
Proposed Technical Specification Changes (Mark-Up) - Unit 2
- 3.
Revised (Typed) Technical Specification Pages - Unit 1
- 4.
Revised (Typed) Technical Specification Pages - Unit 2
- 5.
Calculation 04KV-0001, 4.16 kV Emergency Bus (Loss of Voltage) Undervoltage and Time Delay Uncertainty and Setpoint Calculation (For 4kV 1-E1(E2)-
AE7(AG5)-27/59E and 2-E3(E4)-AI3(AK0)-27/59E)
RA-18-0148 Enclosure Page 2 of 7
- 1.
SUMMARY
DESCRIPTION Pursuant to 10 CFR 50.90, Duke Energy Progress, LLC (Duke Energy), is requesting an amendment associated with Technical Specification (TS) 3.3.8.1, Loss of Power (LOP)
Instrumentation, for the Brunswick Steam Electric Plant (BSEP), Unit Nos. 1 and 2. The proposed change revises the Allowable Values associated with Function 1.b, (i.e., 4.16 kV Emergency Bus Undervoltage (Loss of Voltage) - Time Delay) of Table 3.3.8.1-1, Loss of Power Instrumentation.
- 2.
DETAILED DESCRIPTION 2.1 System Design and Operation The BSEP Class 1E Electrical Power Distribution System AC sources consist of the offsite power sources (i.e., preferred and alternate power sources), and the onsite standby power sources (i.e., Emergency Diesel Generators (EDGs) 1, 2, 3, and 4). The design of the AC electrical power system provides independence and redundancy to ensure an available source of power to the Engineered Safety Feature (ESF) systems.
The Class 1E AC distribution system is divided into redundant load groups, so loss of any one group does not prevent the minimum safety functions from being performed. Each load group has access to two offsite power supplies (i.e., one preferred and one alternate) via a balance of plant (BOP) circuit path. This BOP circuit path consists of the BOP bus and the associated circuit path (i.e., master/slave breakers and interconnecting cables) to a 4.16 kV emergency bus. Each load group can also be connected to a single EDG.
The onsite standby power source for 4.16 kV emergency buses E1, E2, E3, and E4 consists of four EDGs. Each EDG is dedicated to its associated emergency bus. An EDG starts automatically on a loss of coolant accident (LOCA) signal from either Unit 1 or Unit 2 or under emergency bus degraded voltage or undervoltage conditions. After the EDG has started, it automatically ties to its respective bus after offsite power is tripped as a consequence of emergency bus undervoltage or degraded voltage, independent of or coincident with a LOCA signal. Following the trip of offsite power, all loads are stripped from the 4160 V emergency bus except the 480 V emergency bus. When the EDG is tied to the emergency bus, select safety related loads are then sequentially connected to their respective emergency bus by individual timers associated with each auto-connected load following a permissive from a voltage relay monitoring each emergency bus.
A loss of voltage on a 4.16 kV emergency bus indicates that offsite power may be completely lost to the respective emergency bus and is unable to supply sufficient power for proper operation of the applicable equipment. The 27/59E relays (i.e., 1-E1-AE7-27/59E, 1-E2-AG5-27/59E, 2-E3-AI3-27/59E, 2-E4-AK0-27/59E) perform load shedding on emergency buses during loss of voltage conditions. The loss of voltage relay strips the rotating loads and cross-tie breakers from the emergency bus to provide a permissive for the diesel generator output breaker to close and restore power to the bus and applicable equipment when the bus voltage drops below the Loss of Voltage Function Allowable Values (i.e., loss of voltage with a short time delay). The loss of voltage relay also provides a trip signal to the incoming line breaker to the associated emergency bus to allow the diesel generator to connect to the emergency bus.
RA-18-0148 Enclosure Page 3 of 7 2.2 Current Technical Specification Requirements Currently, the Allowable Value associated with Function 1.b, (i.e., 4.16 kV Emergency Bus Undervoltage (Loss of Voltage) - Time Delay) of Table 3.3.8.1-1, Loss of Power Instrumentation, is 0.5 seconds and 2.0 seconds.
2.3 Reason for the Proposed Change The proposed change revises the Allowable Value for the Time Delay Loss of Voltage relays to resolve a design vulnerability impacting the EDG output breaker logic. Under certain conditions, it is possible that the EDG output breaker could close and then immediately trip and lockout.
The proposed change eliminates this potential.
2.4 Description of the Proposed Change The Allowable Value associated with Function 1.b, (i.e., 4.16 kV Emergency Bus Undervoltage (Loss of Voltage) - Time Delay) of Table 3.3.8.1-1, Loss of Power Instrumentation, is being revised to 1.35 seconds and 3.0 seconds. There are no TS Bases changes required to support this change.
Duke Energy requests that, once approved, the amendment shall be implemented prior to the end of the 2023 Unit 2 refueling outage. Post-maintenance testing of the required setpoint changes requires performance of a Loss-of-Coolant Accident / Loss-of-Offsite Power (LOCA/LOOP) test per Surveillance Requirement 3.8.1.14. This test can only be performed with Unit 1 in Mode 4 or 5 for EDGs 1 and 2 and with Unit 2 in Mode 4 or 5 for EDGs 3 and 4.
As a result, the final EDG will have the revised 4.16 kV Emergency Bus Undervoltage (Loss of Voltage) - Time Delay setpoint implemented during the 2023 Unit 2 Refueling outage, currently scheduled to begin in March 2023.
- 3.
TECHNICAL EVALUATION The proposed change revises the Allowable Value for the Time Delay Loss of Voltage relays to resolve a design vulnerability impacting the EDG output breaker logic. Currently, while an EDG is running at rated voltage and frequency and in manual mode (i.e., either from the control room or locally), there is a potential that the EDG output breaker logic scheme could result in a failure of EDG output breakers to remain closed to the emergency bus following an undervoltage signal. The condition is associated with the timing between the RCR-X and 27/59E relays. If an EDG automatic start signal is generated while the EDG is being tested (i.e., in manual mode),
the EDG output breaker will receive a trip signal from the RCR-X relay. This allows the EDG to revert to automatic mode and the EDG output breaker would then automatically reclose onto the emergency bus if the closure permissives are met. The permissives for automatic closure of the EDG output breaker are (1) the EDG is at rated voltage and frequency; (2) an undervoltage condition sensed on the emergency bus, and emergency bus breakers (i.e., CL-A or CL-B) open; and (3) the load sequencing relays must be reset.
With the current Allowable Value for the Time Delay Loss of Voltage relays, it is possible the EDG output breaker close permissive will be made prior to the RCR relay operation. The breaker will close and immediately trip and lockout when the RCR relay, which controls the RCR-X relay, energizes and then times out. If the CL-A or CL-B relay operates before the RCR-X, the EDG breaker will close, then trip once the RCR-X operates. After the RCR-X relay
RA-18-0148 Enclosure Page 4 of 7 de-energizes, the output breaker anti-pump circuit will energize since the closing springs are still charging. This will prevent the breaker from closing until the close signal is removed.
The 27/59E operates the 27EX auxiliary relay which trips the emergency bus incoming line and 4 kV motor load breakers. Auxiliary contacts on these breakers operate the CL-A and CL-B relays. Changes to the 27/59E time delay values will ensure upon a loss of voltage condition on the 4.16 kV emergency bus the CL-A / CL-B relay logic will not operate before the RCR-X relay changes state and cause a EDG output breaker lockout.
The new Allowable Values for the time delay are based on nominal trip setpoints (NTSPs) which were conservatively chosen to account for total device uncertainties and includes margin from the Lower and Upper Design Limits. The lower and upper Allowable Values considered both the respective Design Limits and the As-Found Tolerance for the time delay function. Adequate margin was built into the lower and upper Allowable Values to ensure margin is maintained from their respective Design Limits and to ensure the time delay NTSP will operate within its lower and upper Allowable Values between calibration.
The new Allowable Values for the time delay were established in BSEP Calculation 04KV-0001, 4.16 kV Emergency Bus (Loss of Voltage) Undervoltage and Time Delay Uncertainty and Setpoint Calculation (For 4kV 1-E1(E2)-AE7(AG5)-27/59E and 2-E3(E4)-AI3(AK0)-27/59E).
Calculation 04KV-0001 determined that the Upper Design Limit for the 4.16 kV Emergency Bus (Loss of Voltage) Time Delay shall be less than the assumed time for the EDG restoring bus voltage and frequency. The time assumed for 4.16 kV emergency bus restoration is 13 seconds. 04KV-0001 conservatively uses 3.5 seconds as the Upper Design Limit.
Revision 2 of this calculation is included as Attachment 5 of this enclosure.
Currently, the EDGs are declared inoperable when they are running in manual mode and the output breaker is open.
- 4.
REGULATORY EVALUATION 4.1 Applicable Regulatory Requirements/Criteria 10 CFR 50.36, Technical specifications, provides the requirements for the content required in the TSs. As stated in 10 CFR 50.36, the TSs include, among other things, Limiting Conditions for Operation (LCO) and Surveillance Requirements (SR) to assure that the necessary quality of systems and components is maintained, that facility operation will be within safety limits, and that the limiting conditions for operation will be met.
The proposed change revises the Allowable Values associated with Function 1.b, (i.e., 4.16 kV Emergency Bus Undervoltage (Loss of Voltage) - Time Delay) of Table 3.3.8.1-1, Loss of Power Instrumentation. These Allowable Values are applicable to performance of channel calibrations per Surveillance Requirement (SR) 3.3.8.1.2 and logic system functional tests per SR 3.3.8.1.4. The change is being made to resolve a design vulnerability impacting the EDG output breaker logic; thereby ensuring reliability of the onsite AC electrical sources.
The BSEP design was reviewed for construction under the General Design Criteria for Nuclear Power Plant Construction, issued for comment by the AEC in July 1967, and is committed to meet the intent of the General Design Criteria (GDC), published in the Federal Register on May 21, 1971, as Appendix A to 10 CFR Part 50. The following GDC are applicable to this amendment request.
RA-18-0148 Enclosure Page 5 of 7 GDC 17, Electric power systems, states that an onsite electric power system and an offsite electric power system shall be provided to permit functioning of structures, systems, and components important to safety. The safety function for each system (assuming the other system is not functioning) shall be to provide sufficient capacity and capability to assure that (1) specified acceptable fuel design limits and design conditions of the reactor coolant pressure boundary are not exceeded as a result of anticipated operational occurrences and (2) the core is cooled and containment integrity and other vital functions are maintained in the event of postulated accidents.
GDC 18, Inspection and testing of electric power systems, states that electric power systems important to safety shall be designed to permit appropriate periodic inspection and testing of important areas and features, such as wiring, insulation, connections, and switchboards, to assess the continuity of the systems and the condition of their components. The systems shall be designed with a capability to test periodically (1) the operability and functional performance of the components of the systems, such as onsite power sources, relays, switches, and buses, and (2) the operability of the systems as a whole and, under conditions as close to design as practical, the full operation sequence that brings the systems into operation, including operation of applicable portions of the protection system, and the transfer of power among the nuclear power unit, the offsite power system, and the onsite power system.
The proposed change does not impact the physical function of plant structures, systems, or components (SSC) or the manner in which SCCs perform their design function. As such, the intent of GDC 17 continues to be met. The proposed change is being made to resolve a design vulnerability impacting the EDG output breaker logic; thereby ensuring reliability of the onsite AC electrical sources. Therefore, the intent of GDC 18 continues to be met.
Therefore, based on the considerations discussed above, Duke Energy has determined that the proposed change does not require any exemptions or relief from regulatory requirements, other than revising the TS, and does not affect conformance with the intent of any GDC differently than described in the Updated Final Safety Analysis Report (UFSAR).
4.2 No Significant Hazards Consideration Determination Analysis Duke Energy Progress, LLC (Duke Energy), is requesting an amendment associated with Technical Specification (TS) 3.3.8.1, Loss of Power (LOP) Instrumentation, for the Brunswick Steam Electric Plant (BSEP), Unit Nos. 1 and 2. The proposed change revises the Allowable Value associated with Function 1.b, (i.e., 4.16 kV Emergency Bus Undervoltage (Loss of Voltage) - Time Delay) of Table 3.3.8.1-1, Loss of Power Instrumentation. The Allowable Value for the time delay is being revised from 0.5 seconds and 2.0 seconds to 1.35 seconds and 3.0 seconds.
Duke Energy has evaluated whether a significant hazards consideration is involved with the proposed amendment(s) by focusing on the three standards set forth in 10 CFR 50.92, Issuance of amendment, as discussed below:
RA-18-0148 Enclosure Page 6 of 7
- 1.
Does the proposed change involve a significant increase in the probability or consequences of an accident previously evaluated?
Response: No The proposed change does not involve a physical alteration of the plant (i.e., no new or different type of equipment will be installed). The proposed change revises the Allowable Value for the Time Delay Loss of Voltage relays to resolve a design vulnerability potentially impacting the Emergency Diesel Generator (EDG) output breaker logic; thereby ensuring reliability of the onsite AC electrical sources. Therefore, the proposed change does not adversely affect the ability of structures, systems and components (SSCs) to perform their intended safety function to mitigate the consequences of an initiating event within the assumed acceptance limits. Further, the proposed change does not increase the types and the amounts of radioactive effluent that may be released, nor significantly increase individual or cumulative occupation/public radiation exposures.
Therefore, the proposed amendments do not involve a significant increase in the probability or consequences of an accident previously evaluated.
- 2.
Does the proposed change create the possibility of a new or different kind of accident from any accident previously evaluated?
Response: No The proposed change revises the Allowable Value for the Time Delay Loss of Voltage relays. It does not require any modification to the plant and it does not alter the design configuration, or method of operation of plant equipment beyond its normal functional capabilities. The proposed change will not introduce failure modes that could result in a new accident, and the change does not alter assumptions made in the safety analysis.
Therefore, the proposed amendments do not create the possibility of a new or different kind of accident from any accident previously evaluated.
- 3.
Does the proposed change involve a significant reduction in a margin of safety?
Response: No The proposed change revises the Allowable Value for the Time Delay Loss of Voltage relays to resolve a design vulnerability potentially impacting the EDG output breaker logic; thereby ensuring reliability of the onsite AC electrical sources. It does not alter or exceed a design basis or safety limit. There is no change being made to safety analysis assumptions or the safety limits that would adversely affect plant safety as a result of the proposed change. Margins of safety are unaffected by the proposed change and the applicable requirements of 10 CFR 50.36(c)(3) and 10 CFR 50, Appendix A will continue to be met.
Therefore, the proposed amendments do not result in a significant reduction in the margin of safety.
Based on the above, Duke Energy concludes that the proposed amendment presents no significant hazards consideration under the standards set forth in 10 CFR 50.92(c), and, accordingly, a finding of "no significant hazards consideration" is justified.
RA-18-0148 Enclosure Page 7 of 7 4.3 Conclusion In conclusion, based on the considerations discussed above, (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commissions regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.
- 5.
ENVIRONMENTAL CONSIDERATION A review has determined that the proposed amendment would change a requirement with respect to installation or use of a facility component located within the restricted area, as defined in 10 CFR 20, or would change an inspection or surveillance requirement. However, the proposed amendment does not involve (i) a significant hazards consideration, (ii) a significant change in the types or a significant increase in the amounts of any effluents that may be released offsite, or (iii) a significant increase in individual or cumulative occupational radiation exposure. Accordingly, the proposed amendment meets the eligibility criterion for categorical exclusion set forth in 10 CFR 51.22(c)(9). Therefore, pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the proposed amendment.
- 6.
REFERENCES None.
RA-18-0148 Enclosure Proposed Technical Specification Changes (Mark-Up)
Unit 1
LOP Instrumentation 3.3.8.1 Brunswick Unit 1 3.3-71 Amendment No. 239 Table 3.3.8.1-1 (page 1 of 1)
Loss of Power Instrumentation FUNCTION REQUIRED CHANNELS PER BUS SURVEILLANCE REQUIREMENTS ALLOWABLE VALUE
- 1.
4.16 kV Emergency Bus Undervoltage (Loss of Voltage)
- a.
Bus Undervoltage 1
SR 3.3.8.1.2 SR 3.3.8.1.4 3115 V and 3400 V
- b.
Time Delay 1
SR 3.3.8.1.2 SR 3.3.8.1.4 0.5 seconds and 2.0 seconds
- 2.
4.16 kV Emergency Bus Undervoltage (Degraded Voltage)
- a.
Bus Undervoltage 3
SR 3.3.8.1.1 SR 3.3.8.1.3 SR 3.3.8.1.4 3706 V and 3748 V
- b.
Time Delay 3
SR 3.3.8.1.1 SR 3.3.8.1.3 SR 3.3.8.1.4 9.0 seconds and 11.0 seconds 1.35 3.0
RA-18-0148 Enclosure Proposed Technical Specification Changes (Mark-Up)
Unit 2
LOP Instrumentation 3.3.8.1 Brunswick Unit 2 3.3-71 Amendment No. 267 Table 3.3.8.1-1 (page 1 of 1)
Loss of Power Instrumentation FUNCTION REQUIRED CHANNELS PER BUS SURVEILLANCE REQUIREMENTS ALLOWABLE VALUE
- 1.
4.16 kV Emergency Bus Undervoltage (Loss of Voltage)
- a.
Bus Undervoltage 1
SR 3.3.8.1.2 SR 3.3.8.1.4 3115 V and 3400 V
- b.
Time Delay 1
SR 3.3.8.1.2 SR 3.3.8.1.4 0.5 seconds and 2.0 seconds
- 2.
4.16 kV Emergency Bus Undervoltage (Degraded Voltage)
- a.
Bus Undervoltage 3
SR 3.3.8.1.1 SR 3.3.8.1.3 SR 3.3.8.1.4 3706 V and 3748 V
- b.
Time Delay 3
SR 3.3.8.1.1 SR 3.3.8.1.3 SR 3.3.8.1.4 9.0 seconds and 11.0 seconds 1.35 3.0
RA-18-0148 Enclosure Revised (Typed) Technical Specification Pages Unit 1
LOP Instrumentation 3.3.8.1 Brunswick Unit 1 3.3-71 Amendment No. 239 Table 3.3.8.1-1 (page 1 of 1)
Loss of Power Instrumentation FUNCTION REQUIRED CHANNELS PER BUS SURVEILLANCE REQUIREMENTS ALLOWABLE VALUE
- 1.
4.16 kV Emergency Bus Undervoltage (Loss of Voltage)
- a.
Bus Undervoltage 1
SR 3.3.8.1.2 SR 3.3.8.1.4 3115 V and 3400 V
- b.
Time Delay 1
SR 3.3.8.1.2 SR 3.3.8.1.4 1.35 seconds and 3.0 seconds
- 2.
4.16 kV Emergency Bus Undervoltage (Degraded Voltage)
- a.
Bus Undervoltage 3
SR 3.3.8.1.1 SR 3.3.8.1.3 SR 3.3.8.1.4 3706 V and 3748 V
- b.
Time Delay 3
SR 3.3.8.1.1 SR 3.3.8.1.3 SR 3.3.8.1.4 9.0 seconds and 11.0 seconds
RA-18-0148 Enclosure Revised (Typed) Technical Specification Pages Unit 2
LOP Instrumentation 3.3.8.1 Brunswick Unit 2 3.3-71 Amendment No. 267 Table 3.3.8.1-1 (page 1 of 1)
Loss of Power Instrumentation FUNCTION REQUIRED CHANNELS PER BUS SURVEILLANCE REQUIREMENTS ALLOWABLE VALUE
- 1.
4.16 kV Emergency Bus Undervoltage (Loss of Voltage)
- a.
Bus Undervoltage 1
SR 3.3.8.1.2 SR 3.3.8.1.4 3115 V and 3400 V
- b.
Time Delay 1
SR 3.3.8.1.2 SR 3.3.8.1.4 1.35 seconds and 3.0 seconds
- 2.
4.16 kV Emergency Bus Undervoltage (Degraded Voltage)
- a.
Bus Undervoltage 3
SR 3.3.8.1.1 SR 3.3.8.1.3 SR 3.3.8.1.4 3706 V and 3748 V
- b.
Time Delay 3
SR 3.3.8.1.1 SR 3.3.8.1.3 SR 3.3.8.1.4 9.0 seconds and 11.0 seconds
RA-18-0148 Enclosure Calculation 04KV-0001, 4.16 kV Emergency Bus (Loss of Voltage) Undervoltage and Time Delay Uncertainty and Setpoint Calculation (For 4kV 1-E1(E2)-AE7(AG5)-27/59E and 2-E3(E4)-AI3(AK0)-27/59E)
CALCULATION COVER SHEET 4.16 KV EMERGENCY BUS (LOSS OF VOLTAGE) UNDERVOLTAGE AND TIME DELAY UNCERTAINTY AND SETPOINT CALCULATION (FOR 4kV 1-E1(E2)-AE7(AG5)-27/59E AND 2-E3(E4)-AI3(AK0)-27/59E)
Calculation Number:
04KV-0001 Rev #
2 System:
5170 DSD List:
Yes No
[BNP, HNP, RNP] Sub-Type:
ICS Microfiche Attachment List:
Yes No Quality Level A
Priority E:
Yes No All BNP Unit
____1&2_____
CNS Unit HNP Unit MNS Unit ONS Unit RNP Unit WLS Unit LNP Unit HAR Unit General Office Keowee Hydro Station Originated By Design Verification Review By Approved By Signature Signature Signature E-Signature E-Signature E-Signature Verification Method 1
2 3
Other Printed Name Printed Name Printed Name P. Matt Hauser B. Neal Bowman Steve Kronenwetter Date Date Date E-Date E-Date E-Date YES NO Check Box for Multiple Originators or Design Verifiers (see next page)
For Vendor Calculations:
Vendor: N/A Vendor Document #: N/A Owners Review By: N/A Date: N/A Approval By: N/A Date: N/A
Calculation No. 04KV-0001 Page No. ii of vi Revision 2 List of Affected Pages Body of Calculation (including appendices)
Supporting Documents Rev. #
Pages Revised Pages Deleted Pages Added Rev. #
Type Pages Revised Pages Deleted Pages Added 2
i-vi 2
Attachment A A1-A2 2
1-26 2
Attachment B B1 B2-B4 2
Attachment C C1 C2 2
Attachment D ALL 1
2
Calculation No. 04KV-0001 Page No. iii of vi Revision 2 Revision Summary Revision Summary 0
Original Issue 1
Revise to reflect that this loop contains a primary element uncertainty associated with the potential transformer.
2 Revised the TDU, ALT, AFT, NTSP, and AV for the 27/59E time delay to resolve NCON 02012638 as evaluated in EC 412705. The 27/59E voltage reset TDU, ALT, AFT, and NTSP have been be revised as well. Additionally, the calculation's cover sheet, list of affected pages, revision summary, document indexing table, and table of contents has been updated to requirements in AD-EG-ALL-1117. PDF file converted to.docx. Relevant references have been updated. Due to the extent of changes the calculation has been revised in its entirety.
Calculation No. 04KV-0001 Page No. iv of vi Revision 2 DOCUMENT INDEXING TABLE The purpose of this table is to list cross-references.
Document Type (e.g., CALC, DWG, Procedure, Tag, Software)
Document Number (e.g., Calculation Number, Equipment Tag Number, Procedure Number, Software Name and Version)
Function IN for Design Inputs; OUT for Affected Documents Relationship to this Calculation (e.g., Design Input, Assumption Basis, Reference, Document affected by results)
Tag 1-E1-AE7-27/59E OUT Calibration data affected by results Tag 1-E2-AG5-27/59E OUT Calibration data affected by results Tag 2-E3-AI3-27/59E OUT Calibration data affected by results Tag 2-E4-AK0-27/59E OUT Calibration data affected by results Procedure 1MST-DG23AR OUT Calibration data affected by results Procedure 1MST-DG23BR OUT Design Input Procedure 2MST-DG23AR OUT Design Input Procedure 2MST-DG23BR OUT Design Input Licensing Doc UFSAR IN Design Input Licensing Doc U1 and U2 Tech Spec OUT Document Affected by Results Drawing LL-09111 SH10 IN Reference Drawing LL-09112 SH10 IN Reference Drawing LL-09113 SH10 IN Reference Drawing LL-09114 SH10 IN Reference Calculation BNP-MECH-RBER-001 IN Design Input Calculation BNP-E-7.002 OUT Documented Affected By Results
Calculation Number: 04KV-0001 Revision Number: 2 Page: v of vi TABLE OF CONTENTS Section Description Page List of Affected Pages............................................................................................ ii Revision Summary............................................................................................... iii Document Indexing Table..................................................................................... iv Table of Contents................................................................................................ v 1.0 Objective.............................................................................................................. 1 2.0 Loop Functional Description................................................................................. 1 2.1 Description................................................................................................ 1 2.2 Loop Diagram........................................................................................... 2 3.0 References........................................................................................................... 3 3.1 Drawings................................................................................................... 3 3.2 Vendor Manuals........................................................................................ 4 3.3 Procedures............................................................................................... 4 3.4 Design Basis Documents........................................................................... 5 3.5 CP&L Design Guides................................................................................ 5 3.6 Industry Standards..................................................................................... 5 3.7 Other References..................................................................................... 5 4.0 Inputs and Assumptions....................................................................................... 6 5.0 Determination of Instrument Uncertainties........................................................... 8 5.1 Process Measurement Error...................................................................... 8 5.2 Instrument Uncertainties............................................................................ 9 6.0 Calculation of Loop Uncertainties....................................................................... 19 6.1 Error Propagation.................................................................................... 19 6.2 Loop Uncertainties................................................................................... 20 7.0 Determination of Trip Setpoint............................................................................ 20 7.1 Process Limits......................................................................................... 20 7.2 Setpoint Determination............................................................................ 21 7.3 Graphical Representation of Setpoint...................................................... 23 8.0 Discussion of Results......................................................................................... 25 8.1 Summary of Results................................................................................. 25 8.2 Recommended Action.............................................................................. 25
Calculation Number: 04KV-0001 Revision Number: 2 Page: vi of vi TABLE OF CONTENTS (CONTINUED)
Attachments Number of Pages ATTACHMENT A - Telecon Record............................................................................... 2 ATTACHMENT B - Record of Design Verification.......................................................... 1 ATTACHMENT C - Megger SMRT36 Data Sheet.......................................................... 1
Calculation Number: 04KV-0001 Revision Number: 2 Page: 1 of 26 1.0 OBJECTIVE The objective of this calculation is to determine the Allowable Values (AV) and Setpoint (SP) for the 4.16kV Emergency Bus (Loss of Voltage) Undervoltage and Time Delay functions under normal environmental conditions. These values are produced to support the Improved Technical Specification Project.
The appropriate use of this calculation to support design or station operations activities, other than those specified above, are the responsibility of that user.
2.0 LOOP FUNCTIONAL DESCRIPTION 2.1.
Description Emergency AC Power is provided by four diesel engine driven generators, each supplying power to its own 4.16 kV emergency bus. Emergency Diesel Generators EDG 1 and EDG 2 and associated 4.16 kV emergency buses E1 and E2 are primarily Unit 1 while EDG 3, EDG 4, Bus E3, and Bus E4 are primarily Unit 2. However, there are RHR and Conventional Service Water system loads fed from the opposite unit's emergency power systems making Brunswick a multiple unit site with a "shared emergency power system". (Reference 3.4.1)
The "shared" Diesel Generator Emergency Power Subsystem includes four 4.16 kV emergency switchgear buses E1, E2, E3, and E4, which are normally fed from 4.16 kV BOP buses 1D, 1C, 2D, and 2C respectively, and alternately from diesel generators EDG1, 2, 3, and 4, respectively during emergency conditions.
(Reference 3.4.1)
The Emergency Diesel Generators will auto-start, via the use the use of independent automatic logic for each emergency bus, on any of the following conditions:
a)
Loss of offsite power to either Unit 1 or Unit 2; b)
Unit trip of either unit; c)
Engineered safety features actuation signal (Loss of Coolant Accident -
LOCA) on either unit; d)
Loss of voltage on the associated emergency bus. (Reference 3.7.2)
The 4.16 kV emergency buses are normally fed from their corresponding unit's 4.16 kV BOP buses. Upon loss of all offsite and unit auxiliary power, the emergency buses are powered by the emergency diesel generator units. Each 4.16 kV emergency bus is capable of being fed from any one of two other
Calculation Number: 04KV-0001 Revision Number: 2 Page: 2 of 26 emergency buses by closing the two tie breakers between them. (Reference 3.4.1)
The undervoltage protection controls for safety related systems are designed to be controlled primarily by the signals from a relay located on the emergency bus.
Backup control signals sensed by BOP buses are provided to increase the reliability of the control function. (Reference 3.4.1)
Undervoltage relays (devices 27/59S, 27/59U, and 27) on the BOP buses are designed to detect a loss of voltage and are wired to trip all feeder breakers to the emergency buses on undervoltage and shed loads on the BOP buses. The degraded voltage relays (device 27DV) monitor the voltage on the emergency buses and trip the corresponding incoming line master and slave breakers during "degraded" voltage conditions. The 27/59E relays perform load shedding on emergency buses during "loss of voltage" conditions. (Reference 3.4.1)
In the event of a loss of normal power to the emergency bus, the master breaker will trip which then trips the slave breaker. This isolates the emergency bus from potential electrical faults. The undervoltage condition is sensed by the 27/59E relay which activates the undervoltage circuitry. The associated undervoltage relays energize, tripping the emergency bus load breakers with the exception of the 480V emergency unit substation breaker. This minimizes the connected load when the diesel generator ties into the emergency bus.
The Equipment Data Base System (EDBS) lists the Emergency Bus Over/Under Voltage Relays as Q-Class A, Non-Environmentally Qualified, and Seismic Class
- 1. The uncertainties in this calculation are determined for normal temperature, pressure, and humidity conditions since the relays do not perform a safety function relative to an accident scenario. A seismic uncertainty will be included, if applicable, for an Operating Basis Earthquake (OBE) to cover the possibility of sequential accident conditions.
2.2.
Loop Diagram Diesel Generator Emergency Bus Load Shedding Relays E
1-E1(E2)-AE7(AG5)-27/59E 2-E3(E4)-AI3(AK0)-27/59E Emergency Bus Undervoltage Circuitry
Calculation Number: 04KV-0001 Revision Number: 2 Page: 3 of 26 Instrument Tag No.
Manufacturer Model Location 1-E1-AE7-27/59E General Electric IAV53K Diesel Generator Bldg. 50' El.
1-E2-AG5-27/59E General Electric IAV53K Diesel Generator Bldg. 50' El.
2-E3-Al3-27/59E General Electric IAV53K Diesel Generator Bldg. 50' El.
2-E4-AK0-27/59E General Electric IAV53K Diesel Generator Bldg. 50' El.
3.0 REFERENCES
3.1.
Drawings 3.1.1.
LL-09111. Sheet 0005, Revision 008, 4160 Volt Switchgear "E1" Front View 3.1.2.
LL-09111, Sheet 0006, Revision 020, 4160 Volt Switchgear "E1" Device List 3.1.3.
LL-09111, Sheet 0010, Revision 013, 4160 Volt Switchgear "E1" Compartment "AE7" PT Compartment Control Wiring Diagram 3.1.4.
LL-09112, Sheet 0005, Revision 014, 4160 Volt Switchgear "E2" Front View 3.1.5.
LL-09112, Sheet 0006, Revision 020, 4160 Volt Switchgear "E2" Device List 3.1.6.
LL-09112, Sheet 0010, Revision 013, 4160 Volt Switchgear "E2" Compartment "AG5" PT Compartment Control Wiring Diagram 3.1.7.
LL-09113, Sheet 0005, Revision 010, 4160 Volt Switchgear "E3" Front View 3.1.8.
LL-09113, Sheet 0006, Revision 020, 4160 Volt Switchgear "E3" Device List 3.1.9.
LL-09113, Sheet 0010, Revision 014, 4160 Volt Switchgear "E3" Compartment "Al3" PT Compartment Control Wiring Diagram 3.1.10.
LL-09114, Sheet 0005, Revision 012, 4160 Volt Switchgear "E4" Front View 3.1.11.
LL-09114, Sheet 0006, Revision 020, 4160 Volt Switchgear "E4" Device List 3.1.12.
LL-09114, Sheet 0010, Revision 013, 4160 Volt Switchgear "E4"
Calculation Number: 04KV-0001 Revision Number: 2 Page: 4 of 26 Compartment "AKO" PT Compartment Control Wiring Diagram 3.1.13.
0-FP-03094, Revision B, 4160V, 3phase, 3W, 60Hz 4kV Switchgear Bus Section E2 General Arrangement 3.1.14.
0-FP-03097, Revision A, 4160V, 3phase, 3W, 60Hz 4kV Switchgear Bus Section E1 General Arrangement 3.1.15.
0-FP-03132, Revision F, 4160V, 3phase, 3W, 60Hz 4kV Switchgear Bus Section E4 General Arrangement 3.1.16.
F-03004, Revision 019, 4160 Volt Emergency System Swgr. E1 & E2 Auxiliary One Line Diagram 3.1.17.
F-03003, Revision 019, 4160 Volt Emergency System Swgr. E3 & E4 Auxiliary One Line Diagram 3.1.18.
F-03077, Sheet 0001, Revision 016, Units No. 1 & 2 4160 Volt Switchgear "E1" Div. I Relaying & Metering Three Line Diagram 3.1.19.
F-03078, Sheet 0001, Revision 015, Units No. 1 & 2 4160 Volt Switchgear "E2" Div. II Relaying & Metering Three Line Diagram 3.1.20.
F-03079, Sheet 0001, Revision 015, Units No. 1 & 2 4160 Volt Switchgear "E3" Div. I Relaying & Metering Three Line Diagram 3.1.21.
F-03080, Sheet 0001, Revision 016, Units No. 1 & 2 4160 Volt Switchgear "E4" Div. II Relaying & Metering Three Line Diagram 3.1.22.
F-03012, Sheet 0008, Revision 005, Emergency Swgr. E4 Fdr. Brkrs.
Tie Brkrs. E4 to E2 & E4 to E3 Logic Diagram 3.1.23.
F-03012, Sheet 0010, Revision 005, Emergency Swgr. E3 Fdr. Brkrs.
Tie Brkrs. E3 to E1 & E3 to E4 Logic Diagram 3.1.24.
F-03012, Sheet 0012, Revision 005, Emergency Swgr. E2 Fdr. Brkrs.
Tie Brkrs. E2 to E1 & E2 to E4 Logic Diagram 3.1.25.
F-03012, Sheet 0014, Revision 005, Emergency Swgr. E1 Fdr. Brkrs.
Tie Brkrs. E1 to E2 & E1 to E3 Logic Diagram 3.1.26.
D-03056, Revision 013, Normal & Accident Conditions Service Environment Chart 3.2.
Vendor Manuals 3.2.1.
FP-84569, Revision R, Relays 3.3.
Procedures 3.3.1.
1MST-DG23AR, Revision 003, DG Undervoltage Relay 27/59E Emergency Bus E1 Channel CAL 3.3.2.
1MST-DG23BR, Revision 003, DG Undervoltage Relay 27/59E Emergency Bus E2 Channel CAL 3.3.3.
2MST-DG23AR, Revision 003, DG Undervoltage Relay 27/59E
Calculation Number: 04KV-0001 Revision Number: 2 Page: 5 of 26 Emergency Bus E3 Channel CAL 3.3.4.
2MST-DG23BR, Revision 003, DG Undervoltage Relay 27/59E Emergency Bus E4 Channel CAL 3.3.5.
0PIC-RLY026, Revision 026, Relay Calibration Using Relay Software and Relay Tester 3.3.6.
AD-EG-ALL-1110, Revision 005, Design Review Requirements 3.3.7.
AD-EG-ALL-1117, Revision 005, Design Analyses and Calculations 3.3.8.
EGR-NGGC-0153, Revision 012, Engineering Instrument Setpoints 3.4.
Design Basis Documents 3.4.1.
DBD-50, Revision 016, AC Electrical System 3.4.2.
DBD-37.4, Revision 015, Diesel Generator Building Ventilation Air System 3.4.3.
Deleted 3.5.
CP&L Design Guides 3.5.1.
Deleted. See 3.3.8.
3.6.
Industry Standards and References 3.6.1.
ISA Standard S67.04.01-2000, Setpoints for Nuclear Safety-Related Instrumentation (Information Only) 3.6.2.
ISA Standard S67.04.02-2000, Methodologies for the Determination of Setpoints for Nuclear Safety-Related Instrumentation (Information Only) 3.6.3.
USNRC Regulatory Guide 1.105, Revision 2, Instrument Setpoints for Safety Related Systems (Information Only) 3.7.
Other References 3.7.1.
Equipment Data Base System (EDBS) 3.7.2.
Updated Final Safety Analysis Report (UFSAR), Amendment 25, Section 8.3, Onsite Power Systems 3.7.3.
TSC 96TSB02, Technical Specification Change Request for Improved Technical Specifications and 24 Month Fuel Cycle 3.7.4.
BNP-E-7.002, Revision 013, AC Auxiliary Electrical Distribution System Voltage / Load Flow / Fault Current Study 3.7.5.
Resolution to PUR/ITS/24 Month Open Item #488, Requesting Upper and Lower Design Limits for 4.16 kV Emergency Bus Undervoltage -
Loss of Voltage Function (see Attachment 2 of EC 412705, R0) 3.7.6.
9527-001-3-ED00-12-F, Revision 0, dated 10/28/75, UE&C 4160V Coordination Study
Calculation Number: 04KV-0001 Revision Number: 2 Page: 6 of 26 3.7.7.
Technical Specifications - Unit 1, Amendment 282 3.7.8.
Technical Specifications - Unit 2, Amendment 310 3.7.9.
Technical Specification Bases - Unit 1, Revision 98 3.7.10.
Technical Specification Bases - Unit 2, Revision 97 3.7.11.
145-002, Revision 6, Specification for 4160 Volt Switchgear 3.7.12.
BNP-MECH-RBER-001, Revision 2, Reactor Building Environmental Report 3.7.13.
EC 412705. Revision 0, EDG Output Breaker Undervoltage Dropout Relay NTSP and Technical Specification AV Change 3.7.14.
04KV-0002, Revision 4, 4.16 kV Emergency Bus Degraded Grid Voltage Relay Setpoint Calculation 4.0 INPUTS AND ASSUMPTIONS 4.1.
The Lower Design Limit for the 4.16kV Emergency Bus (Loss of Voltage)
Undervoltage function is 87.14 VAC. This voltage represents the equivalent 4.16 kV motor terminal voltage of 3050 volts as referenced in Reference 3.7.5. The 87.14 VAC takes into consideration the turndown ratio (35:1) of the Potential Transformer (PT) and was calculated as follows: 3050 ÷ (4200 ÷ 120) = 87.14 VAC (rounded).
4.2.
The Upper Design Limit for the 4.16kV Emergency Bus (Loss of Voltage)
Undervoltage function is 98.89 VAC. This voltage represents the equivalent 4.16 kV motor terminal voltage of 3461 volts as referenced in Reference 3.7.5. The 98.89 VAC takes into consideration the turndown ratio (35:1) of the Potential Transformer (PT) and was calculated as follows: 3461 ÷ (4200 ÷ 120) = 98.89 VAC (rounded).
4.3.
The Lower Design Limit for the 4.16kV Emergency Bus (Loss of Voltage) Time Delay shall ensure that each Emergency Diesel Generator output breaker will close. NCR 2008253, DG1 Output Breaker Failed to Remain Closed During LOOP/LOCA Test, a design vulnerability in the EDG output breaker logic was identified. The vulnerability applies when the EDG is running unloaded in manual mode. In this condition, a loss of offsite power can result in the EDG output breaker closing and then immediately opening and locking out. The vulnerability is a relay race in the diesel logic. If the CL-A or CL-B relay operates before the RCR-X, the EDG breaker will close, then trip once the RCR-X operates. After the RCR-X relay drops out, the output breaker anti-pump circuit will energize since the closing springs are still charging. This will prevent the breaker from closing until the close signal is removed.
To ensure following a loss of voltage condition on the 4.16 kV Emergency Bus (t
= 0 seconds) the EDG breaker does not lock-out, the CL-A / CL-B relay logic shall not operate before the RCR-X relay changes state. EC 412705 calculates
Calculation Number: 04KV-0001 Revision Number: 2 Page: 7 of 26 the 27/59E relay shall not operate before t = 1 second to ensure the CL-A / CL-B relays do not change state before the RCR-X relay changes state. This calculation will conservatively use 1.20 seconds as the Lower Design Limit.
4.4.
The Upper Design Limit for the 4.16kV Emergency Bus (Loss of Voltage) Time Delay shall be less than the assumed time for the EDG restoring bus voltage and frequency. The time assumed for 4.16 kV Emergency Bus restoration is 13 seconds (Ref. 3.7.13), which includes the diesel starting time (10 seconds) plus a 3 second delay for instrument lag. This calculation will conservatively use 3.5 seconds as the Upper Design Limit.
4.5.
Deleted.
4.6.
The normal and accident temperature ranges in the 4160 Volt Switchgear Room of the Diesel Generator Building as found in the Service Environment Chart (Reference 3.1.26) and Reference 3.4.2 are as follows:
Normal Accident Minimum 40°F 40°F Average 70°F 70°F Maximum 120°F 120°F 4.7.
Accident effects are considered N/A for the purposes of this calculation due to the location of the Emergency Bus Over/Undervoltage Relay being in the Diesel Generator Building which is not expected to see any harsh environments as a result of any accident scenario.
4.8.
The calibration frequency of the Emergency Bus Over/Undervoltage Relays, as they appear in Section 2.2, is based on 15 months (12 months plus a 25% grace period).
4.9.
The Emergency Bus Over/Undervoltage Relays are required to be operable to support the requirements of Improved Technical Specifications during the following conditions: 1) Modes 1, 2, and 3, and; 2) When the associated diesel generator is required to be operable per the "AC Sources - Shutdown" requirement.
4.10. Response time for this function is not assumed in any of the plant accident analyses or Technical Specifications. Therefore, response time for this function is considered not applicable.
4.11. The Lower Design Limit for the 4.16 kV Emergency Bus (Degraded Voltage) Bus Undervoltage) Bus Undervoltage function (Dropout Setting) is 3698 (Ref. 3.7.14).
The maximum acceptable reset voltage will be taken as 3598 assuming a 100 VAC margin.
4.12. The time characteristic of the 27/59E IAV53K relay is automatically determined by the setting of the ratio of the voltage to close the right contacts (drop-out /
undervoltage condition) to the voltage to close the left contacts (pick-up / reset condition). (Ref. 3.2.1, Page S18-40 and S18-52)
Calculation Number: 04KV-0001 Revision Number: 2 Page: 8 of 26 4.13. Based upon Input 4.12 the 27/59E undervoltage time delay is a function of the ratio of the dropout setpoint and reset setpoint. The existing dropout setpoint will be maintained and the reset setpoint will be adjusted in order to obtain the required time delay. Its desirable that the reset voltage be as close as possible to the drop out setting and the dropout voltage will be taken as 92% of the reset voltage. Therefore, the new reset setpoint can be calculated as 101 VAC by dividing the existing dropout setpoint of 93 VAC by 92% (93 VAC / 0.92). This voltage represents the equivalent 4.16 kV motor terminal voltage of 3535 volts as referenced in Reference 3.7.5. The 101 VAC takes into consideration the turndown ratio (35:1) of the Potential Transformer (PT) and was calculated as follows: 3535 ÷ (4200 ÷ 120) = 101 VAC (rounded). The reset voltage is sufficiently between the dropout voltage of 3255 VAC (93 VAC
- 35) and the maximum acceptable reset voltage of 3598 VAC (Ref. Input 4.11).
4.14. Extrapolating the time-voltage dropout curve for the IAV53K relay (Ref. 3.2.1, S18-52) on the 92% dropout curve arrives at a time delay value of approximately 1.87 seconds. The following provides a detailed explanation of determining the time delay value:
- At 95% dropout curve the relay has a time delay of 1.15 seconds @ 0% VAC
- At 90% dropout curve the relay has a time delay of 2.35 seconds @ 0% VAC
- Extrapolating between 90% and 95% dropout curves provides the following time delays @ 0% VAC:
Time-Voltage Curve (%)
Time Delay (s) @ 0% VAC 95 1.15 94 1.39 93 1.63 92 1.87 91 2.11 90 2.35 5.0 DETERMINATION AND INSTRUMENT UNCERTAINTIES 5.1.
Process Measurement Error 5.1.1. Process Measurement Effects (PME)
There are no process effects associated with the measurement of overvoltage or undervoltage relative to this instrument loop. As a result, PME is considered N/A.
PME =
N/A
Calculation Number: 04KV-0001 Revision Number: 2 Page: 9 of 26 5.1.2. Primary Element Accuracy (PEA)
The potential transformer (PT) between the 4 kV and the 120 VAC circuits is the primary element of the loop. The PT has a turndown ratio of 35:1.
The accuracy of the PT is +/- 0.3% of the turns ratio per the information contained in References 3.7.1(11).
PEA =
+/- 0.3% x 101 VAC
+/- 0.303 VAC 5.2. Instrument Uncertainties 5.2.1. General Electric Model IAV53K Over & Undervoltage Relay - Undervoltage Function Range: 55 to 140 VAC (Ref. 3.2.1) 5.2.1.1.
Reference Accuracy () (Attachment A)
Per the information contained in Attachment A, the reference accuracy of the relay is +/- 2.00% of setting.
RA =
+/- 2.00% of setting
+/-.02 x 101 VAC
+/- 2.02 VAC 5.2.1.2.
Drift () (Attachment A and Ref. 3.5.1)
Per the information contained in Attachment A, drift for the relay is unknown. Per the guidance provided in Section 9.4.2 of Reference 3.5.1, a drift value can be inferred from an analysis of the device's calibration history, specifically from As-Found/As-Left data. Using the As-Found and As-Left data values from past performances of procedures 1(2)MST-DG23A(B)R, it has been determined in Revision 0 of 04KV-0002 that a value of 2.0%
of full scale for an eighteen-month period will be utilized. The current calibration interval (1 year) plus its grace period of 25% is 1.25 years. Conservatively, a drift value of +/-1.0% full scale bounds the current calibration interval plus its grace period.
Calculation Number: 04KV-0001 Revision Number: 2 Page: 10 of 26 DR =
+/- 2.0% of full scale
+/- 0.02 x 140 VAC
+/- 2.8 VAC 5.2.1.3.
Temperature Effect () (Attachment A)
The temperature effect is +/- 7.00% of setting over a temperature range of -20°C to +55°C per the information in Attachment A.
Linearizing this effect over the temperature span of-20°C to +55°C
(-4°F to +131°F equivalent) produces an uncertainty of+/- 0.052% /
°F. The maximum ambient temperature difference between calibration and operating conditions is 55°F (based on a maximum Diesel Generator Building temperature of 120°F per Reference 3.4.2 minus a minimum calibration temperature of 65°F per Section 9.4.3 of Reference 3.5.1).
TE =
+/- 0.052% x 55°F = +/- 2.86% of setting
+/-.0286 x 101 VAC
+/- 2.80 VAC 5.2.1.4.
Static Pressure Effect ()
Static pressure effect is only applicable to differential pressure devices in high static pressure process service. Emergency Bus Over/Undervoltage Relays are electronic instruments which do not experience any process pressure. Static pressure effect is considered N/A for the purposes of this calculation.
SPE =
N/A 5.2.1.5.
Overpressure Effect ()
Overpressure effect is applicable only to those instruments which may experience a higher process pressure than the pressure at which the instrument is rated. Emergency Bus Over/Undervoltage Relays are electronic instruments which do not experience any direct contact with process pressure and therefore will not
Calculation Number: 04KV-0001 Revision Number: 2 Page: 11 of 26 experience an overpressure effect. Overpressure effect is considered N/A for the purposes of this calculation.
OP =
N/A 5.2.1.6.
Power Supply Effect () (Attachment A)
Power supply effect on the trip setpoint of the Emergency Bus Over/Undervoltage Relay is considered N/A per the information contained in Attachment A.
PSE=
N/A 5.2.1.7.
Accident Temperature Effect ()
Per Step 4.7 of this calculation, Accident Temperature Effect associated with an accident scenario is considered N/A.
ATE=
N/A 5.2.1.8.
Accident Pressure Effect ()
Per Step 4.7 of this calculation, Accident Pressure Effect associated with an accident scenario is considered N/A.
APE=
N/A 5.2.1.9.
Accident Radiation Effect ()
Per Step 4.7 of this calculation, Accident Radiation Effect associated with an accident scenario is considered N/A.
ARE=
N/A 5.2.1.10.
Seismic Effect () (Attachment A)
Per the information contained in Attachment A, the relay was subjected to 6 g's without experiencing any misoperation while in the Non-operated mode. The Non-operated mode is when the relay voltage is between the undervoltage and overvoltage trip setpoints. There is no uncertainty associated with the seismic effect up to this value per Attachment A and therefore, seismic
Calculation Number: 04KV-0001 Revision Number: 2 Page: 12 of 26 effect is considered N/A.
SE=
N/A 5.2.1.11.
Readability ()
The Emergency Bus Over/Undervoltage Relay does not have an indicator which is considered in this uncertainty and Setpoint calculation. The final output device of this instrument loop is not an indicator or recorder, therefore readability effect is considered N/A.
RE=
N/A 5.2.1.12.
Setpoint With a Single Side of Interest A single side of interest is not considered due to the conservative nature of the calculation and the guidance provided in Reference 3.5.1 which states that other methods of reducing conservatism should be used prior to considering a single side of interest.
Therefore, any effect associated with single side of interest is considered N/A.
5.2.1.13.
Humidity Effect () (Ref. 3.1.26 and Attachment A)
The humidity in the 4160 Volt Switchgear Room of the Diesel Generator Building varies from 20 to 90% per Reference 3.1.26.
The information in Attachment A states that humidity effect is considered unknown due to this parameter not being evaluated.
Therefore, for the purposes of this calculation, humidity effect shall be considered negligible.
HE =
0.00 VAC 5.2.1.14.
Calibration Tolerance () (Ref. 3.3.1 and 3.5.1)
The Calibration Tolerance as found in 1(2)MST-DG23A(B)R and EDB is +/- 1.96 VAC. Per the guidance provided in Section 9.5.1.1 of Reference 3.5.1, the minimum requirement for the calibration tolerance should normally be equal to the reference accuracy.
Therefore, Calibration Tolerance shall be equal to the Reference Accuracy value of +/- 2.02 VAC.
Calculation Number: 04KV-0001 Revision Number: 2 Page: 13 of 26 CAL = +/- 2.02 VAC 5.2.1.15.
Measuring and Test Equipment Error () (Ref. 3.3.5, Attachment C)
A Megger Pulsar, MPRT, or SMRT 36 is used to calibrate the VAC undervoltage setpoint of the relay per 0PIC-RLY026. Currently, a Megger Relay Test System - SMRT36 is the relay test system of choice for 0PIC-RLY026.
The SMRT36 has a typical accuracy of +/-0.05% reading + 0.02%
range and a bounding accuracy of +/-0.15% reading + 0.05% range for 0-150VAC, 0 to 50°C. The bounding accuracy will be utilized in this calculation. The respective 27/59 relays are calibrated on the bench within its operating environment, thus there are no temperature effects associated with the SMRT36.
MTE = +/- 0.15% x reading + 0.05% x range
+/- 0.15% x 101 VAC + 0.05% x 150 VAC
+/- 0.147 VAC + 0.075 VAC
+/- 0.23 VAC 5.2.1.16.
Bias ()
No bias effects have been identified, therefore bias shall be considered N/A.
B =
N/A 5.2.1.17.
As-Found Tolerance ()
AFT
=
+/-ALT
+ DR
+ MTE
=
+/-2.02+ 2.8+ 0.23
=
+/-3.46 VAC
Calculation Number: 04KV-0001 Revision Number: 2 Page: 14 of 26 5.2.1.18.
As-Left Tolerance ()
=
Calibration Tolerance
=
+/-2.02 VAC 5.2.1.19.
Total Device Uncertainty ()
TDU
=
+/-PEA+ RA+ DR+ TE+ CAL+ MTE
=
+/-0.294 + 2.02+ 2.8+ 2.89+ 2.02 + 0.23
=
+/-5.04 VAC 5.2.2. General Electric Model IAV53K Over & Undervoltage Relay - Time Delay Function Range: 1 to 15 seconds (Ref. 3.2.1) 5.2.2.1.
Reference Accuracy () (Ref. 3.7.5 and Attach. A)
Per the information contained in Attachment A, the reference accuracy of the time delay of the relay is +/- 7.00% of setting.
However, for the purposes of this calculation, a reference accuracy of +/- 15.00% of setting per Reference 3.7.5 will be used.
RA =
+/- 15.00% of setting
+/- 0.15 X 1.87 seconds
+/- 0.28 seconds 5.2.2.2.
Drift () (Attachment A and Ref. 3.5.1)
Per the information contained in Attachment A, drift for the time delay of the relay is unknown. Per Section 9.4.2 of Ref. 3.5.1 a drift value of +/-1.0% full scale for 18 months will be utilized. The current calibration interval (1 year) plus its grace period of 25% is 1.25 years. Conservatively, a drift value of +/-1.0% full scale bounds the current calibration interval plus its grace period.
Calculation Number: 04KV-0001 Revision Number: 2 Page: 15 of 26 DR =
+/- 1.0% of full scale
+/- 0.01 x 15 seconds
+/- 0.15 seconds 5.2.2.3.
Temperature Effect () (Attachment A)
The temperature effect is +/- 10.00% of setting over a temperature range of -20°C to +55°C per the information in Attachment A.
Linearizing this effect over the temperature span of -20°C to +55°C
(-4°F to +131°F equivalent) produces an uncertainty of+/- 0.074% /
°F. The maximum ambient temperature difference between calibration and operating conditions is 55°F (based on a maximum Diesel Generator Building temperature of 120°F per Reference 3.4.2 minus a minimum calibration temperature of 65°F per Section 9.4.3 of Reference 3.5.1).
TE =
+/- 0.074% x 55°F = +/- 4.07% of setting
+/-.0407 x 1.87 seconds
+/- 0.08 seconds 5.2.2.4.
Static Pressure Effect ()
Static pressure effect is only applicable to differential pressure devices in high static pressure process service. Emergency Bus Over/Undervoltage Relays are electronic instruments which do not experience any process pressure. Static pressure effect is considered N/A for the purposes of this calculation.
SPE =
N/A 5.2.2.5.
Overpressure Effect ()
Overpressure effect is applicable only to those instruments which may experience a higher process pressure than the pressure at which the instrument is rated. Emergency Bus Over/Undervoltage Relays are electronic instruments which do not experience any direct contact with process pressure and therefore will not experience an overpressure effect. Overpressure effect is
Calculation Number: 04KV-0001 Revision Number: 2 Page: 16 of 26 considered N/A for the purposes of this calculation.
OP =
N/A 5.2.2.6.
Power Supply Effect ()
Power supply effect on the trip setpoint of the Emergency Bus Over/Undervoltage Relay is considered N/A per the information contained in Attachment A.
PSE=
N/A 5.2.2.7.
Accident Temperature Effect ()
Per Step 4.7 of this calculation, Accident Temperature Effect associated with an accident scenario is considered N/A.
ATE=
N/A 5.2.2.8.
Accident Pressure Effect ()
Per Step 4.7 of this calculation, Accident Pressure Effect associated with an accident scenario is considered N/A.
APE=
N/A 5.2.2.9.
Accident Radiation Effect ()
Per Step 4.7 of this calculation, Accident Radiation Effect associated with an accident scenario is considered N/A.
ARE=
N/A 5.2.2.10.
Seismic Effect ()
Per the information contained in Attachment A, the relay was subjected to 6 g's without experiencing any misoperation while in the Non-operated mode. The Non-operated mode is when the relay voltage is between the undervoltage and overvoltage trip setpoints. There is no uncertainty associated with the seismic effect up to this value per Attachment A and therefore, seismic effect is considered N/A.
Calculation Number: 04KV-0001 Revision Number: 2 Page: 17 of 26 SE=
N/A 5.2.2.11.
Readability ()
The Emergency Bus Over/Undervoltage Relay does not have an indicator which is considered in this uncertainty and Setpoint calculation. The final output device of this instrument loop is not an indicator or recorder, therefore readability effect is considered N/A.
RE=
N/A 5.2.2.12.
Setpoint With a Single Side of Interest A single side of interest is not considered due to the conservative nature of the calculation and the guidance provided in Reference 3.5.1 which states that other methods of reducing conservatism should be used prior to considering a single side of interest. Therefore, any effect associated with single side of interest is considered N/A.
5.2.2.13.
Humidity Effect ()
The humidity in the 4160 Volt Switchgear Room of the Diesel Generator Building varies from 20 to 90% per Reference 3.1.26.
The information in Attachment A states that humidity effect is considered unknown due to this parameter not being evaluated.
Therefore, for the purposes of this calculation, humidity effect shall be considered negligible.
HE =
0.00 seconds 5.2.2.14.
Calibration Tolerance () (Ref. 3.3.1 and 3.5.1)
Per the guidance provided in Section 9.5.1.1 of Reference 3.5.1, the minimum requirement for the calibration tolerance should normally be equal to the reference accuracy. Therefore, Calibration Tolerance shall be equal to the Reference Accuracy value of +/- 0.28 seconds.
CAL =
+/- 0.28 seconds
Calculation Number: 04KV-0001 Revision Number: 2 Page: 18 of 26 5.2.2.15.
Measuring and Test Equipment Error () (Ref. 3.3.5, Attachment C)
A Megger Pulsar, MPRT, or SMRT 36 is used to calibrate the VAC undervoltage setpoint of the relay per 0PIC-RLY026. Currently, a Megger Relay Test System - SMRT36 is the relay test system of choice for 0PIC-RLY026.
The SMRT36 has a typical accuracy of +/-0.001% reading +/-2 LSD and a bounding accuracy of +/- 0.005% reading +/-2 LSD for 0.0001 to 99999.9 seconds, 0 to 50°C. The bounding accuracy will be utilized in this calculation. The respective 27/59 relays are calibrated on the bench within its operating environment, thus there are no temperature effects associated with the SMRT36.
MTE = +/- 0.005% x reading +/- 2 least significant digit
+/- 0.005% x 1.87 seconds + 0.0001 seconds
+/- 0.00009 seconds + 0.0002 seconds
+/- 0.000029 seconds Therefore, for purposes of this calculation MTE will be taken as negligible.
5.2.2.16.
Bias ()
No bias effects have been identified, therefore bias shall be considered N/A.
B =
N/A 5.2.2.17.
As-Found Tolerance ()
AFT
=
+/-ALT
+ DR
+ MTE
=
+/-0.28 + 0.15 + 0
=
+/-0.32 seconds
Calculation Number: 04KV-0001 Revision Number: 2 Page: 19 of 26 5.2.2.18.
As-Left Tolerance ()
=
Calibration Tolerance
=
+/-0.28 seconds 5.2.2.19.
Total Device Uncertainty ()
TDU
=
+/-RA+ DR+ TE+ CAL+ MTE
=
+/-0.28+ 0.15+ 0.08+ 0.28 + 0
=
+/-0.43 seconds 6.0 CALCULATION OF LOOP UNCERTAINTIES 6.1. Error Propagation 6.1.1. Group As-Found Tolerances (GAFT) 6.1.1.1.
GAFT =
+/- AFT
+/- 3.46 VAC 6.1.1.2.
GAFT =
+/- AFT
+/- 0.32 seconds 6.1.2. Loop As-Found Tolerances (LAFT) 6.1.2.1.
LAFT - Emergency Bus Over/Undervoltage Relay -
Undervoltage LAFT =
+/- AFT
+/- 3.46 VAC 6.1.2.2.
LAFT - Emergency Bus Over/Undervoltage Relay - Time Delay LAFT =
+/- AFT
Calculation Number: 04KV-0001 Revision Number: 2 Page: 20 of 26
+/- 0.32 seconds 6.1.3. Loop As-Left Tolerances (LALT) 6.1.3.1.
LALT - Emergency Bus Over/Undervoltage Relay -
Undervoltage LALT =
+/- ALT
+/- 2.02 VAC 6.1.3.2.
LALT - Emergency Bus Over/Undervoltage Relay - Time Delay LALT =
+/- ALT
+/- 0.28 seconds 6.2. Loop Uncertainties 6.2.1. Total Loop Uncertainty (TLU) - Emergency Bus Over / Undervoltage Relay
- Undervoltage TLU =
+/- TDU
+/- 5.04 VAC 6.2.2. Total Loop Uncertainty (TLU) - Emergency Bus Over / Undervoltage Relay -
Time Delay TLU =
+/- TDU
+/- 0.43 seconds 7.0 DETERMINATION OF TRIP SETPOINT 7.1. Process Limits 7.1.1. Analytical / Design Limit The Lower Design Limit for the 4.16kV Emergency Bus (Loss of Voltage)
Undervoltage function is 87.14 VAC. This voltage represents the equivalent 4.16 kV motor terminal voltage of 3050 volts as referenced in Reference
Calculation Number: 04KV-0001 Revision Number: 2 Page: 21 of 26 3.7.5. The 87.14 VAC takes into consideration the turndown ratio (35:1) of the Potential Transformer (PT) and was calculated as follows: 3050 +
(4200 + 120) = 87.14 VAC (rounded).
The Upper Design Limit for the 4.16kV Emergency Bus (Loss of Voltage)
Undervoltage function is 98.89 VAC. This voltage represents the equivalent 4.16 kV motor terminal voltage of 3461 volts as referenced in Reference 3.7.5. The 98.89 VAC takes into consideration the turndown ratio (35:1) of the Potential Transformer (PT) and was calculated as follows: 3461 +
(4200 + 120) = 98.89 VAC (rounded).
To ensure following a loss of voltage condition on the 4.16 kV Emergency Bus (t
= 0 seconds) the EDG breaker does not lock-out, the CL-A / CL-B relay logic shall not operate before the RCR-X relay changes state. EC 412705 calculates the 27/59E relay shall not operate before t = 1 second to ensure the CL-A / CL-B relays do not change state before the RCR-X relay changes state. This calculation will conservatively use 1.25 seconds as the Lower Design Limit.
The Upper Design Limit for the 4.16kV Emergency Bus (Loss of Voltage) Time Delay all be less than the assumed time for the EDG restoring bus voltage and frequency. The time assumed for 4.16 kV Emergency Bus restoration is 13 seconds (Ref. 3.7.13), which includes the diesel starting time (10 seconds) plus a 3 second delay for instrument lag. This calculation will conservatively use 3.5 seconds as the Upper Design Limit.
7.1.2. Operational Limit The Operational Limits for Emergency Bus (Loss of Voltage) Relay-Bus Undervoltage and Time Delay functions are considered N/A based on the setpoints being bounded by the calculated Upper and Lower Allowable Values for these functions.
7.2. Setpoint Determination 7.2.1. Emergency Bus Over / Undervoltage Relay - Bus Undervoltage NOTE: Emergency Bus Voltages in Parentheses Parameter Value Equation Notes Upper Design Limit (UDL) 98.89 VAC (3461.00 VAC)
N/A Ref. 3.7.5
& Sect. 4.0
Calculation Number: 04KV-0001 Revision Number: 2 Page: 22 of 26 Margin 0.82 VAC N/A Margin 0.17 VAC N/A Margin 0.28 VAC N/A Total Loop Uncertainty 5.04 VAC N/A Sect. 6.2.1 Other Uncertainties 1.58 VAC OU = TLU - LAFT Loop As-Found Tolerance 3.46 VAC LAFT = AFT Loop As-Left Tolerance 2.02 VAC LALT = ALT Upper Allowable Value 97.14 VAC
( 3400.00 VAC)
UAV = UDL - OU - M Setpoint 93.00 VAC (3255.00 VAC)
SP = LDL + TLU + M Lower Allowable Value 89.00 VAC
( 3115.00 VAC)
LAV = LDL + OU + M Reset Value 101 VAC (3535.00 VAC)
N/A Sect. 4.0 Lower Design Limit (LDL) 87.14 VAC (3050.00 VAC)
N/A Ref. 3.7.5
& Sect. 4.0 7.2.2. Emergency Bus Over / Undervoltage Relay - Time Delay Parameter Value Equation Notes Upper Design Limit (UDL) 3.50 seconds N/A Ref. 3.7.12 Margin 1.20 seconds N/A Margin 0.04 seconds N/A Margin 0.39 seconds N/A Total Loop Uncertainty 0.43 seconds N/A Other Uncertainties 0.11 seconds OU = TLU - LAFT Loop As-Found Tolerance 0.32 seconds LAFT = AFT Loop As-Left Tolerance 0.28 seconds LALT = ALT Upper Allowable Value 3.00 seconds UAV = UDL - OU - M Setpoint 1.87 seconds SP = UDL - TLU - M Sect. 4.0
Calculation Number: 04KV-0001 Revision Number: 2 Page: 23 of 26 Lower Allowable Value 1.35 seconds LAV = LDL + OU + M Reset Value N/A N/A Lower Design Limit (LDL) 1.20 seconds N/A Sect. 4.0 7.3. Graphical Representation of Setpoint 7.3.1. Emergency Bus Over / Undervoltage Relay - Bus Undervoltage 96.46 VAC (ULAFT) 95.02 VAC (ULALT) 93.00 VAC (SP) 90.98 VAC (LLALT) 89.54 VAC (LLAFT) 87.14 VAC (LDL) 98.89 VAC (UDL) 2.02 VAC (ULALT) 2.02 VAC (LLALT) 3.46 VAC (ULAFT) 3.46 VAC (LLAFT)
Voltage 97.14 VAC (UAV) 89.00 VAC (LAV)
Calculation Number: 04KV-0001 Revision Number: 2 Page: 24 of 26 7.3.2. Emergency Bus Over / Undervoltage Relay - Time Delay 2.19 SEC (ULAFT) 2.15 SEC (ULALT) 1.87 SEC (SP) 1.59 SEC (LLALT) 1.55 SEC (LLAFT) 1.20 SEC (LDL) 3.50 SEC (UDL) 0.28 SEC (ULALT) 0.28 SEC (LLALT) 0.32 SEC (ULAFT) 0.32 SEC (LLAFT)
Time 3.00 SEC (UAV) 1.35 SEC (LAV)
Calculation Number: 04KV-0001 Revision Number: 2 Page: 25 of 26 8.0 DISCUSSION OF RESULTS 8.1. Summary of Results 8.1.1. Emergency Bus (Loss of Voltage) Over / Undervoltage Relay - Bus Undervoltage NOTE:
Emergency Bus Voltages in Parentheses Upper Design Limit
=
98.89 VAC (3461.00 VAC)
Upper Allowable Value
= 97.14 VAC ( 3400.00 VAC)
Setpoint
=
93.00 VAC (3255.00 VAC)
Lower Allowable Value
= 89.00 VAC ( 3050.00 VAC)
Lower Design Limit
=
87.14 VAC (3050.00 VAC) 8.1.2. Emergency Bus (Loss of Voltage) Over / Undervoltage Relay - Time Delay Upper Design Limit
=
3.50 seconds Upper Allowable Value
= 3.00 seconds Setpoint
=
1.87 seconds Lower Allowable Value
= 1.35 seconds Lower Design Limit
=
1.20 seconds 8.2.
Recommended Action 8.2.1. It is recommended the ALT, AFT, and reset setpoint for the Emergency Bus (Loss of Voltage) Over/Undervoltage Relay - Bus Undervoltage as they appear in Section 7.2 of this calculation be revised in EDB.
8.2.2. It is recommended the ALT, AFT, NTSP, and AV for the Emergency Bus (Loss of Voltage) Over/Undervoltage Relay - Time Delay as they appear in Section 7.2 of this calculation be revised in EDB.
8.2.3. It is recommended the ALT and reset setpoint for the Emergency Bus (Loss of Voltage) Over/Undervoltage Relay - Bus Undervoltage as they appear in Section 7.2 of this calculation be revised in 1(2)MST-DG23A(B)R.
8.2.4. It is recommended the ALT and NTSP for the Emergency Bus (Loss of Voltage) Over/Undervoltage Relay as they appear in Section 7.2 of this
Calculation Number: 04KV-0001 Revision Number: 2 Page: 26 of 26 calculation be revised in 1(2)MST-DG23A(B)R.
8.2.5. It is recommended the NTSP for the Emergency Bus (Loss of Voltage)
Over/Undervoltage Relay - Time Delay as it appears in Section 7.2 of this calculation be revised in the Unit 1 and Unit 2 TRM & UFSAR.
8.2.6. It is recommended the reset setpoint for the Emergency Bus (Loss of Voltage) Over/Undervoltage Relay - Bus Undervoltage as it appears in Section 7.2 of this calculation be revised in the Unit 1 and Unit 2 UFSAR.
8.2.7. It is recommended the AV for the Emergency Bus (Loss of Voltage)
Over/Undervoltage Relay - Time Delay as they appear in Section 7.2 of this calculation be revised in the Unit 1 and Unit 2 Technical Specifications.
8.2.8. It is recommended the NTSP for the Emergency Bus (Loss of Voltage)
Over/Undervoltage Relay - Time Delay as they appear in Section 7.2 of this calculation be revised in BNP-E-7.002, Attachment K.
Calculation: 04KV-0001 Revision Number: 2 Attachment A Page A1 of A2 TELECON RECORD August 15, 1996 TO:
Jim Teague, General Electric Co.
Phone: 610-251-7114 FROM:
Bruce Crabbs, EXCEL Services Corp.
Phone: 910-457-3182 Fax: 910-457-3014
SUBJECT:
General Electric Model IAV53K Relays Mr. Teague was contacted to determine the uncertainties associated with the General Electric Model IAV53K Over/Under Voltage Relays used in the 4.16 kV electrical system at the Brunswick Nuclear Plant. The following information was obtained:
- 1)
Accuracy:
The accuracy of the voltage pickup is 2.00% of setting. The accuracy of the time delay of the relay is 7.00% of setting.
- 2)
Drift and time period:
Unknown, General Electric does not age their relays.
- 3)
Temperature Effect:
The change in voltage in a percentage of setting over a temperature range of -20°C to +55°C is 7.00% with a design null temperature of 25°C (the temperature at which the temperature effect is 0%). The temperature effect for the time delay of the relay is 10% over the same temperature range.
- 4)
Power Supply Effect:
N/A, the relay is a self-powered device with no power supply effect.
Calculation: 04KV-0001 Revision Number: 2 Attachment A Page A2 of A2 TELECON RECORD (CONTD)
- 5)
Seismic Effect:
The seismic effect on the relay is in actuality looking for a
misoperation of the relay.
Non-operated Mode*
Undervoltage Mode Overvoltage Mode Normally Open Contact 6g's**
6g's**
<0.2g's***
Normally Closed Contact 6g's**
0.45g's 6g's**
- The Non-operated mode of the relay is a state of normal voltage in which the voltage being sensed is above the undervoltage setting and below the overvoltage setting of the relay.
- The value of 6g's represents the upper limit of the test equipment used for the seismic testing. This is the value to which the relay was subjected and experienced no misoperation.
- The value of 0.2g's represents the lower limit of the test equipment used to perform the test. The value of < 0.2g's represents that the Normally Open contact of the relay in the Overvoltage Mode experienced misoperation at some value below the lower limit of the test equipment used to perform the test.
- 6)
Humidity Effect:
Unknown due to this parameter not being evaluated and therefore, no data available.
- 7)
Radiation Effect:
The relay is qualified to 1 X 105 Rad with no damage and no uncertainty associated up to this value.
- 8)
RFI/EMI Effect:
N/A due to no electronic components in the relay.
Calculation Number: 04KV-0001 Revision Number: 2 Attachment B Page B1 of B1 Document: 04KV-0001 Revision: 2 The signature of the Design Verification Reviewer confirms:
The type of verification method performed Technical errors have been resolved and the records have been included, if applicable Note:
This Record of Review form may be used to document other reviews, but is only required for Design Verification Reviews.
Reviewer or Concurrent Reviewer Design Verification Review Method Other Records:
Attached Design Review Alternate Calculation Qualification Testing B. Neal Bowman I&C E-Date Reviewer(Print/Sign)
Discipline Date Item No.
Technical Error Resolution
- 1. The time delay value is dependent on the ratio of pickup and dropout voltages for the 27/59E. Need to consider the time-voltage curve for the 27/59E in choosing an appropriate time delay.
Evaluated a new undervoltage reset value against the existing undervoltage dropout value to arrive at an appropriate time delay value. See design inputs 4.12 through 4.14.
- 2. Timer M&TE calculation appears to be in error:
MTE subscript should be "TIMER" not "RELAY" At precisely 2 sec, display should be 2.0000, so LSD should be 0.0001 and 2 LSD would be 0.001 (or 2*LSD is 0.0002?)
Math does not appear to be correct Corrected M&TE timer calculation errors.
- 3.
- 4.
Calculation Number: 04KV-0001 Revision Number: 2 Attachment C Page C1 of C1