NG-08-0366, Technical Specification Change Request (TSCR-106): 4160 Volt Emergency Bus Undervoltage (Degraded Voltage) Maximum Allowable Value Affected Technical Specification: Section 3.3.8.1

Technical Specification Change Request (TSCR-106): 4160 Volt Emergency Bus Undervoltage (Degraded Voltage) Maximum Allowable Value Affected Technical Specification: Section 3.3.8.1

ML081630205
Person / Time
Site:	Duane Arnold
Issue date:	05/30/2008
From:	Richard Anderson Duane Arnold
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
NG-08-0366, TSCR-106
Download: ML081630205 (18)

Text

FPL Energy Duane Arnold, LLC 3277 DAEC Road Palo, Iowa 52324 FPL Energy.

Duane Arnold Energy Center May 30, 2008 NG-08-0366 10 CFR 50.90 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Duane Arnold Energy Center Docket 50-331 License No. DPR-49 Technical Specification Change Request (TSCR-106): "4160 Volt Emergency Bus Undervoltage (Degraded Voltage) Maximum Allowable Value" Affected Technical Specification: Section 3.3.8.1 Pursuant to 10 CFR 50.90, FPL Energy Duane Arnold, LLC (FPL Energy Duane Arnold) hereby requests revision to the Technical Specifications (TS) for the Duane Arnold Energy Center (DAEC). The proposed Amendment revises the TS maximum allowable value for the 4160 volt Emergency Bus Undervoltage (Degraded Voltage) relays. It has been determined that the current TS maximum allowable value constitutes an inadequate TS value per Administrative Letter 98-10, "Dispositioning of Technical Specifications that are Insufficient to Assure Plant Safety." In accordance with Administrative Letter 98-10, administrative controls are in place to ensure that the appropriate maximum allowable value for the 4160 volt Emergency Bus Undervoltage relays is not exceeded. These administrative controls will remain in place until this TS change request has been approved and implemented.

The proposed Amendment presents no significant hazards consideration under the standards set forth in 10 CFR 50.92(c). The Technical Specification Bases are not affected by this proposed Amendment.

FPL Energy Duane Arnold requests approval of the proposed amendment by June 1, 2009.

Once approved, the amendment will be implemented within 30 days.

This application has been reviewed by the DAEC Operations Review Group. A copy of this submittal, along with the 10 CFR 50.92 evaluation of "No Significant Hazards Consideration," is being forwarded to our appointed state official pursuant to 10 CFR 50.91.

This letter makes no new commitments or changes to any existing commitments.

If you have any questions or require additional information, please contact Mr. Steve Catron at (319) 851-7234.

Document Control Desk NG-08-0366 Page 2 I declare under penalty of perjury that the foregoing is true and correct.

Executed on May 30, 2008.

Richard L. Andernb Vice President, Duane Arnold Energy Center FPL Energy Duane Arnold, LLC Exhibits: A) EVALUATION OF PROPOSED CHANGE B) PROPOSED TECHNICAL SPECIFICATION CHANGES (MARK-UP)

C) PROPOSED TECHNICAL SPECIFICATION PAGES (RE-TYPED) cc: Administrator, Region Ill, USNRC Project Manager, DAEC, USNRC Resident Inspector, DAEC, USNRC D. McGhee (State of Iowa)

EXHIBIT A EVALUATION OF PROPOSED CHANGE

Subject:

TSCR-106 - 4160 Volt Emergency Bus Undervoltage (Degraded Voltage)

Maximum Allowable Value

1. DESCRIPTION

2. PROPOSED CHANGE

3. BACKGROUND

3.1 System Description

3.2 DAEC Licensing Basis

4. TECHNICAL ANALYSIS

5. REGULATORY SAFETY ANALYSIS 5.1 No Significant Hazards Consideration 5.2 Applicable Regulatory Requirements/Criteria 5.3 Precedents

6. ENVIRONMENTAL CONSIDERATION

7. REFERENCES Figure 1 DAEC LOCA Response Figure 2 4160 Volt Emergency Bus Undervoltage (Degraded Voltage) Setpoint Relationship

NG-08-0366 Exhibit A Page 1 of 11

1. DESCRIPTION This letter is a request to amend Operating License DPR-49 for the Duane Arnold Energy Center (DAEC). The proposed Amendment would revise the Technical Specifications (TS) maximum allowable value for the 4160 volt Emergency Bus Undervoltage (Degraded Voltage) relays.

The existing requirement, as specified in TS Table 3.3.8.1, requires an allowable voltage range of > 3780V and < 3899V for the 4160 volt Emergency Bus Undervoltage (Degraded Voltage) relays, hereafter referred to as the 4160 volt Emergency Bus Undervoltage relays.

Recent revisions to the setpoint calculation for the 4160 volt Emergency Bus Undervoltage relays have resulted in a maximum allowable voltage level closer to the actual setpoint voltage limit. The revised calculation supports a maximum allowable voltage of < 3822V for the 4160 volt Emergency Bus Undervoltage relays versus the existing requirement of < 3899V. As such, the current TS maximum allowable relay setpoint value is above that needed to ensure operability of the offsite sources. FPL Energy Duane Arnold, LLC (FPL Energy Duane Arnold) has performed surveillance on the 4160 volt Emergency Bus Undervoltage relays to ensure the allowed voltage falls within the newly calculated values of > 3780V and < 3822V. FPL Energy Duane Arnold has established administrative controls to ensure that the newly calculated maximum allowable value of < 3822V for the 4160 volt Emergency Bus Undervoltage relays is not

.exceeded.

2. PROPOSED CHANGE The holders of license DPR-49 for the Duane Arnold Energy Center propose to amend the Technical Specifications by deleting the referenced page and replacing it with the enclosed new page.

SUMMARY

OF CHANGES:

TS Page 3.3-75 The proposed Amendment revises the TS maximum allowable value for the 4160 volt Emergency Bus Undervoltage relays to the newly calculated value of < 3822V as currently controlled by administrative means.

TS Bases Section 3.3.8.1 states:

The Bus Undervoltage-Allowable Values are low enough to prevent inadvertentpower supply transfer,but high enough to ensure that sufficient power is available to the requiredequipment.

This Technical Specification Bases statement remains valid and is not affected by this proposed Amendment.

NG-08-0366 Exhibit A Page 2 of 11

3. BACKGROUND

3.1 System Description

The Startup Transformer and Standby Transformer are the preferred and alternate preferred sources of offsite power, respectively, to the 4160 volt Emergency Buses.

The 4160 volt Emergency Buses supply power to those auxiliaries and engineered safety features required for safe shutdown.

In order to prevent an unexpected degradation of offsite power from reducing the voltage on the 4160 volt Emergency Buses below the minimum operating voltage for all safety loads, each bus is monitored by four relays. If offsite power experiences a degraded voltage condition, the buses will be disconnected from offsite power and automatically transferred to the onsite emergency diesel generators. A degraded voltage condition is defined as offsite power below the 4160 volt degraded voltage trip setpoint for a specified period of time. The 4160 volt degraded voltage trip setpoint specified is 3797.5 volts and the allowable voltage range of > 3780V and < 3899V. The 4160 volt degraded voltage trip time delay specified is 8.0 seconds and the allowable time delay range of > 7.92 seconds and < 8.5 seconds. The settings established for these relays are chosen so that potential transients on the offsite power grid and bus voltage dips due to the starting of large motors will not cause a spurious transfer from the offsite power source to the onsite emergency diesel generators, see Figure 1.

TS Table 3.3.8-1, Loss of Power Instrumentation, currently requires an allowable voltage range of > 3780V and < 3899V for the 4160 volt Emergency Bus Undervoltage relays. The minimum allowable voltage (i.e., 3780V) is calculated using Reference 1 and is the minimum voltage required to power the safety loads. The minimum allowable voltage value is unchanged. The maximum allowable voltage, also calculated using Reference 1, is established to provide sufficient margin for process, calibration and instrument uncertainties.

During an FPL Energy Duane Arnold review of calculations associated with the alternate preferred offsite power source, it was identified that the Standby Transformer was not capable of providing adequate voltage to the 4160 volt Emergency Buses since the voltage at these Buses may fall well below the degraded voltage setpoint under certain accident conditions. As a result, the alternate preferred offsite power source was declared inoperable at 13:39 hours on November 30, 2007 (see Reference 2.)

To resolve this issue, modifications were made to the Standby Transformer. As part of the Standby Transformer modifications, FPL Energy Duane Arnold recently revised the setpoint calculation for the 4160 volt Emergency Bus Undervoltage relays. The Standby Transformer modifications changed the transformer tap settings and resulted in a reduction in the upper analytical limit for the 4160 volt Emergency Bus Undervoltage relays. At the same time, it was determined that the setpoint calculation should also be revised to reflect current calibration accuracies. As a result, the setpoint calculation for the 4160 volt Emergency Bus Undervoltage relays was revised by reducing uncertainties

NG-08-0366 Exhibit A Page 3 of 11 thereby allowing the maximum allowable voltage level to be closer to the actual setpoint voltage limit.

The existing requirement, as specified in TS Table 3.3.8.1, requires a maximum allowable voltage < 3899V for the 4160 volt Emergency Bus Undervoltage relays. The revised calculation supports a maximum allowable voltage of < 3822V for the 4160 volt Emergency Bus Undervoltage relays. As such, the current TS maximum allowable value for the 4160 volt Emergency Bus Undervoltage relays is above that needed to ensure operability of the offsite sources. Specifically, with degraded voltage relay maximum allowed voltage above 3822V, the grid voltage would need to be maintained artificially high in order to avoid spurious degraded voltage relay actuations. The minimum allowable voltage value and the time delay allowable values for the 4160 volt Emergency Bus Undervoltage relays are unchanged. The frequency of surveillances on the 4160 volt Emergency Bus Undervoltage relays is unchanged.

FPL Energy Duane Arnold has performed surveillances on the 4160 volt Emergency Bus Undervoltage relays to ensure the allowed voltage falls within the newly calculated values of > 3780V and < 3822V. Additionally, FPL Energy Duane Arnold has established administrative controls to ensure that the appropriate maximum allowable value of 3822V for the 4160 volt Emergency Bus Undervoltage relays is not exceeded. Therefore, FPL Energy Duane Arnold is requesting the allowable voltage range for the 4160 volt Emergency Bus Undervoltage relays be narrowed to a range of > 3780V and < 3822V as currently controlled by administrative means. This allowed voltage range will ensure operability of the Emergency Buses should the offsite sources experience a degraded voltage condition.

3.2 DAEC Licensing Basis The current TS Table 3.3.8-1, Loss of Power Instrumentation, requires an allowable voltage range of > 3780V and < 3899V for the 4160 volt Emergency Bus Undervoltage relays. The minimum allowable voltage value of 3780V is unchanged, therefore, the possibility of the 4160 volt Emergency Buses failing to transfer to the emergency diesel generators at voltages below those required to power the safety loads is not introduced.

The DAEC used the GE Setpoint Methodology, Reference 1, to determine the maximum, or upper allowable voltage value (UAV) for the 4160 volt Emergency Bus Undervoltage relays. This methodology was approved by the NRC in a safety evaluation report dated November 6, 1995. The Upper Allowable Value (UAV) for the 4160 volt Emergency Bus Undervoltage relays is based on a revised Upper Analytical Limit (UAL) of 95.5% of Emergency Bus voltage. The UAL is the voltage at which the relay must reset following a degraded voltage transient, to prevent such a degraded voltage signal from inadvertently resulting in a transfer of Emergency Buses to the onsite emergency diesel generators.

The UAV then represents the voltage value for the relay trip (drop out) setpoint to ensure the relay reset occurs prior to the UAL.

The revised UAL is based on the voltage to which the Emergency Bus recovers under

NG-08-0366 Exhibit A Page 4 of 11 worst case grid conditions following a Design Basis Accident - Loss of Coolant Accident (DBA-LOCA) when the bus is supplied by the Standby Transformer. It has been established by analysis that Emergency Bus voltage will recover to 95.5% of nominal voltage.

Applying the revised UAL results in a reduction in the UAV from 3899 (93.73%) volts to 3822 (91.88%) volts on the Emergency Bus. Sufficient margin is maintained to the UAL as demonstrated by the setpoint calculation for the 4160 volt Emergency Bus Undervoltage relays to accommodate the proposed UAV when all applicable instrument uncertainties are considered. The table below summarizes the proposed change:

Nominal Trip Current Proposed Proposed Function and Title Setpoint UAV UAV UAL 4160 V Emergency Bus Primary 3797.5 3899 3822 3972.5 Undervoltage (Degraded Voltage) Secondary 108.5 .111.4 109.2 113.5

% Nominal 91.29% 93.73% 91.88% 95.5%

As discussed above, the FPL Energy Duane Arnold setpoint calculation for the 4160 volt Emergency Bus Undervoltage relays yields a maximum allowable voltage value of 3822V, see Figure 2. The current TS Table 3.3.8-1 required maximum allowable voltage value of 3899V for the 4160 volt Emergency Bus Undervoltage relays is above that currently required for operability of offsite sources. Specifically, if the maximum allowable voltage for the 4160 Volt. Emergency Bus degraded relays were allowed to be set above the proposed limit of 3822V, the relays could trip and separate from a grid that was at a voltage sufficient to support safety loads, i.e., not degraded. This would result in unnecessary transfers of the 4160 volt Emergency Buses from offsite power to the onsite emergency diesel generators. As such, the current TS maximum allowable value of 3899V constitutes an inadequate TS value per Administrative Letter 98-10, "Dispositioning of Technical Specifications that are Insufficient to Assure Plant Safety.". In accordance with Administrative Letter 98-10, administrative controls are in place to ensure that the appropriate maximum allowable value for the 4160 volt Emergency Bus Undervoltage relays is not exceeded. These administrative controls will remain in place until this TS, change has been implemented at which time the TS Table 3.3.8-1, Loss of Power Instrumentation, will properly reflect the allowable voltage range for the 4160 volt Emergency Bus Undervoltage relays.

The proposed change to the maximum allowable voltage for the 4160 volt Emergency Bus Undervoltage relays was reviewed against the draft TSTF-493, Reference 3. The value of offsite AC voltage is not a safety limit for Duane Arnold Energy Center. The proposed change to the maximum allowable voltage for the 4160 volt Emergency Bus Undervoltage relays was reviewed against the draft TSTF-493, Reference 3.* The minimum allowable

NG-08-0366 Exhibit A Page 5 of 11 voltage for the 4160 volt Emergency Bus Undervoltage relays ensures that the Emergency buses are transferred to the onsite emergency diesel generators such that all safety loads are-supplied a voltage greater than the required minimum operating voltage.

The minimum allowable voltage for the 4160 volt Emergency Bus Undervoltage relays is unchanged. The maximum allowable voltage for the 4160 volt Emergency Bus Undervoltage relays functions to prevent potential transients on the offsite power grid and bus voltage dips due to starting of large motors from causing a spurious transfer from offsite power to the onsite emergency diesel generators. The maximum allowable voltage for the 4160 volt Emergency Bus Undervoltage relays does not constitute a Limiting Safety'System Setting (LSSS), therefore, TSTF-493 is not applicable.

In accordance with commitments made in response to Generic Letter 2006-02, the TS Limiting Condition for Operation for inoperable offsite circuits is entered whenever the grid

.operator determines that offsite power grid conditions are such that a trip of the DAEC turbine/generator would lead directly to voltages in the DAEC switchyard below the trip setpoints for Loss of Power Instrumentation. This commitment is unchanged by the proposed TS change.

4. TECHNICAL ANALYSIS The proposed TS change to the allowable voltage range for the 4160 volt Emergency Bus Undervoltage relays ensures operability of the Emergency Buses during degraded voltage conditions. In the event of degraded voltage conditions, the 4160 volt Emergency Bus Undervoltage relays transfer the Emergency Buses to the onsite emergency diesel generators, thereby assuring that the electrical equipment and safety loads are capable of performing their function to meet the requirements of the accident analyses.

5. REGULATORY SAFETY ANALYSIS 5.1 No Significant Hazards Consideration FPL Energy Duane Arnold, LLC has evaluated whether or not a significant hazards consideration is involved with the proposed amendment by focusing on the three standards set forth in 10 CFR 50.92, "Issuance of amendment," as discussed below:

1. Does the proposed amendment involve a significant increase in the probability.

or consequences of an accident previously evaluated?

Response: No.

The proposed TS change to the maximum allowable voltage for the 4160 volt Emergency Bus Undervoltage relays affects when an Emergency Bus that is experiencing degraded voltage will disconnect from offsite power and transfer to an emergency diesel generator.

While the maximum allowed voltage that initiates this action will be lowered, the function remains the same. The maximum allowed voltage has been analyzed to ensure spurious trips will be avoided. The proposed change will not affect any accident initiators. or

NG-08-0366 Exhibit A Page 6 of 11 precursors. As a result, the probability of any accident previously evaluated is not significantly increased.

The consequences of any accident previously evaluated are not increased since the 4160 volt Emergency Bus Undervoltage relays will continue to meet their required function to transfer the 4160 volt Emergency Buses to the emergency diesel generators in the event of a degraded voltage condition on the offsite power supply. This transfer will ensure that the electrical equipment is capable of performing its function to meet the requirements of the accident analyses.

Therefore, the proposed change does not involve a significant increase in the probability or consequences of an accident previously evaluated.

2. Does the proposed amendment create the possibility of a new or different kind of accident from any accident previously evaluated?

Response: No.'

No new or different accidents result from utilizing the proposed change. The proposed TS change to the maximum allowable voltage for the 4160 volt Emergency Bus Undervoltage relays does not affect existing or introduce any new accident precursors or modes of operation. The relays will continue to detect undervoltage conditions and transfer the Emergency Buses to the emergency diesel generators at a voltage adequate to ensure proper safety equipment performance and to prevent equipment damage. The function of the relays remains the same.

Therefore, the proposed change does not create the possibility of a new or different kind of accident from any previously evaluated. *

3. Does the proposed amendment involve a significant reduction in a margin of safety?

Response: No.

The proposed TS change to the maximum allowable voltage for the 4160 volt Emergency Bus Undervoltage relays will allow all safety loads to have sufficient voltage to perform their intended safety functions while ensuring spurious trips are avoided. Thus, the results of the accident analyses will not be affected as the input assumptions are protected.

Therefore, the proposed change does not involve a significant reduction in a margin of safety.

CONCLUSION Based on the preceding 10 CFR 50.92 evaluation FPL Energy Duane Arnold concludes

NG-08-0366 Exhibit A Page 7 of 11 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.

Attorney for Licensee: Marjan Mashhadi, Esquire, Senior Attorney, FPL Energy Duane Arnold, LLC, 801 Pennsylvania Ave., NW, Suite 220 Washington, DC 20004.

5.2 Applicable Regulatory Requirements/Criteria By letter dated May 30, 2008, FPL Energy Duane Arnold, LLC (FPL Energy Duane Arnold) submitted a request for revision of the Technical Specifications (TS) for the Duane Arnold Energy Center (DAEC). The proposed Amendment revises the TS maximum allowable voltage for the 4160 volt Emergency Bus Undervoltage relays from a value of

< 3899 volts to a value of - 3822 volts.

Evaluation:

The proposed change is consistent with the current regulations and thus, an exemption pursuant to 10 CFR 50.12 is not required. The current regulations (e.g., §50.36) do not dictate the allowed voltage range for the 4180 Volt Emergency Bus degraded voltage relays.

UFSAR Chapter 8 provides a description of the DAEC essential distribution system. The DAEC essential distribution system is designed to ensure a supply of electrical power to all plant equipment during normal operation and under abnormal conditions.

The degraded voltage relays assure that power will be available to operate the required emergency loads by functioning to disconnect the 4160 volt Emergency Buses from a degraded offsite power source and transferring the buses to the onsite emergency diesel generators. The allowable voltage values for the 4160 volt Emergency Buses degraded voltage relays have been chosen to assure that required safety-related equipment will be powered from the emergency diesel generators in the event that offsite power is degraded while preventing disconnection from the preferred or alternate preferred power source during momentary offsite power transients.

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 Commission's 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. Therefore, we have concluded that the proposed revision to the DAEC Technical Specifications is acceptable.

NG-08-0366 Exhibit A Page 8 of 11 5.3 Precedents By letters dated April 19, 2002 (ML021000010) and March 26, 2003 (ML030550096), the NRC approved changes-the Technical Specifications allowable values for the 4 kV bus degraded voltage trip setpoint for the Donald C. Cook Nuclear Plant Units 1 and 2, respectively. These changes to the Donald C. Cook Nuclear Plant Units were made as part of enhancements to the entire electrical distribution system.

NG-08-0366 Exhibit A Page 9 of 11

6. ENVIRONMENTAL CONSIDERATION 10 CFR Section 51.22(c)(9) identifies certain licensing and regulatory actions which are eligible for categorical exclusion from the requirement to perform an environmental assessment. A proposed amendment to an operating license for a facility requires no environmental assessment if operation of the facility in accordance with the proposed amendment would not: (1) involve a significant hazards consideration; (2) result in a significant change in the types or significant increase in the amounts of any effluents that may be released offsite; and (3) result in a significant increase in individual or cumulative occupational radiation exposure. FPL Energy Duane Arnold has reviewed this request and determined that the proposed amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR Section 51.22(c)(9). Pursuant to 10 CFR Section 51.22(b),

no environmental impact statement or environmental assessment needs to be prepared in connection with the issuance of the amendment. The basis for this determination follows.

Basis The change meets the eligibility criteria for categorical exclusion set forth in 10 CFR Section 51.22(c)(9) for the following reasons:

1. As demonstrated in the 10 CFR 50.92 evaluation included in this exhibit, the proposed amendment does not involve a significant hazards consideration.

2. The proposed change does not result in an increase in power level, does not increase the production, nor alter the flow path or method of disposal of radioactive waste or byproducts. There is no significant change in the types or significant increase in the amounts of any effluents that may be released offsite.

3. The proposed change does not result in changes in the level of control or methodology used for processing of radioactive effluents or handling of solid radioactive waste nor will the proposal result in any change in the normal radiation levels within the plant.

There is no significant increase in individual or cumulative occupational radiation exposure.

7. REFERENCES

1. GE Report NEDC-31336, GE Proprietary Information, GE Instrument Setpoint Methodology.

2. Licensee Event Report #2007-010-00, dated January 29, 2008 (ML080310367).

3. Technical Specification Task Force Improved Standard Technical Specification Change Traveler, TSTF-493, Revision 3, Clarify Application of Setpoint Methodology for LSSS Functions.

NG-08-0366 Exhibit A Page 10 of 11 Figure 1 DAEC LOCA RESPONSE Essential Bus Voltage in Volts BOP & Essential Loads

-Degraded Voltage Relay Reset-------------

Degraded Voltage Relay Setpoint Essential Loads in MW(e)

I 4

T =15 sec.--> C/D RHR NOT TO T = 10 sec--> A/B RHR SCALE T- 1 min T = 5 sec -- > Core Sprays Aux to Startup Transfer T : 90 sec (Coincident with Reverse Power Trip) Feedpumps Trip I I . ' I I I I Where RHR is Residual Heat Removal BOP is Balance Of Plant

NG-08-0366 Exhibit A Page 11 of 11 Figure 2 4160 Volt Emergency Bus Undervoltage (Degraded Voltage) Setpoint Relationship All Units in volts Upper Analytical Limit 3972 Upper Allowable Value 3822 LER Avoidance Upper NTSP 3804.5 Setpoint/Lower NTSP 3797.5 LER Avoidance Lower Allowable Value 3780 Lower Analytical Limit 3740 Where NTSP is Nominal Trip Setpoint LER is Licensee Event Report

EXHIBIT B PROPOSED TECHNICAL SPECIFICATION (MARK-UP) 1 Page to Follow

LOP Instrumentation 3.3.8.1 Table 3.3.8.1-1 (page 1 of 1)

Loss of Power Instrumentation REQUIRED CHANNELS SURVEILLANCE ALLOWABLE FUNCTION PER BUS REQUIREMENTS VALUE

1. 4.16 kV Emergency Bus Undervoltage (Loss of Voltage)

a. Bus Undervoltage 1 SR 3.3.8.1.2 > 595 V and SR 3.3.8.1.4 < 2275 V SR 3.3.8.1.5

2. 4.16 kV Emergency Bus Undervoltage (Degraded Voltage)

a. Bus Undervoltage 4 SR 3.3.8.1.1 > 3780 V and SR 3.3.8.1.3<

SR 3.3.8.1.5

b. Time Delay 4 SR 3.3.8.1.1 > 7.92 seconds and SR 3.3.8.1.3 < 8.5 seconds SR 3.3.8.1.5

3. 4.16 kV Emergency Transformer 2 SR 3.3.8.1.2 > 2450 V Supply Undervoltage SR 3.3.8.1.3 SR 3.3.8.1.5 DAEC 3.3-75 DAEC .3-75AMonRdmer-t 223

EXHIBIT C PROPOSED TECHNICAL SPECIFICATION PAGES (RE-TYPED) 1 Page to Follow

LOP Instrumentation 3.3.8.1 Table 3.3.8.1-1 (page 1 of 1)

Loss of Power Instrumentation REQUIRED CHANNELS SURVEILLANCE ALLOWABLE FUNCTION PER BUS REQUIREMENTS VALUE

1. 4.16 kV Emergency Bus Undervoltage (Loss of Voltage)

a. Bus Undervoltage 1 SR 3.3.8.1.2 > 595 V and SR 3.3.8.1.4 < 2275 V SR 3.3.8.1.5

2. 4.16 kV Emergency Bus Undervoltage (Degraded Voltage)

a. Bus Undervoltage 4 SR 3.3.8.1.1 > 3780 V and SR 3.3.8.1.3 <3822 V SR 3.3.8.1.5

b. Time Delay 4 SR 3.3.8.1.1 > 7.92 seconds and SR 3.3.8.1.3 < 8.5 seconds SR 3.3.8.1.5

3. 4.16 kV Emergency Transformer 2 SR 3.3.8.1.2 > 2450 V Supply Undervoltage SR 3.3.8.1.3 SR 3.3.8.1.5 DAEC 3.3-75 Amendment