ML20247M440

Forwards Attachments to Advance Response to Special Electrical Team Insp Repts 50-277/89-07 & 50-278/89-07,per

ML20247M440
Person / Time
Site:	Peach Bottom
Issue date:	05/25/1989
From:	Hunger G PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NUDOCS 8906050043
Download: ML20247M440 (16)

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PHILADELPHIA ELECTRIC COMPANY 23o1 MARKET STREET

, P.O. BOX 8699 PHILADELPHIA A. PA.19101 l l mm 84140oo

'May 25, 1989 Docket Nos. 50-277.

50-278 j i

U.S. Nuclear Regulatory Commission Attn: Document Control Desk  :

Washington, DC 20555 .

SUBJECT:

Peach Bottom Atomic Power Station, Units 2 and 3 l Special Electrical Team Inspection 1 50-277/89-07 and 50-278/89-07  :

REFERENCE:

(1) Letter from J. Strosnider (USNRC) to C. A. McNeill, Jr. (PECo), dated April 20, 1989 (2) Letter from S. J. Kowalski (PECo) to U. S. Nuclear Regulatory Commission, dated March 17, 1989 l

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Dear Sirs:

The_ purpose of this letter is to forward for your use a complete copy of the eight individual attachments to our advance response to the Special Electrical Team Inspection (Reference 2) as .

requested by the Reference 1 letter. We are sorry you did not I receive the attachments and also regret any inconvenience our delay in; responding to your letter may have caused.

If you have any further questions regarding our response to the inspection, please do not hesitate to contact us.

i Very truly yours,  ;

1 G. A.

f.

Hunger, Jr.

Director  !

Licensing Section j Nuclear Support Division  ;

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-Attachment  ;

l 8906050043 890525 #

PDR G

ADOCK 05000277 PNV

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< May 25,'.1989' Page 2 i

cc:- . J. Strosnide'r, Chief, Engineering Branch, Division of Reactor Safety, Region I,.USNRC.

Wi T.; Russell,~ Administrator, Region 1, USNRC LT. P. Johnson, USNRC Senior Resident Inspector

. T.'E. Magette, State of Maryland-J. Urban, Delmarva Power R..A. Burricelli, Pub.ic Service Electric & Gas H. C. Schwemm, Atlantic Electric T.-_M. Gerusky, Commonwealth of Pennsylvania l;

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. s Attachment 1 TITLE: VOLTAGE ADEQUACY AT DC MOV's PECO INTERPRETATION OF CONCERN Several potential operability problems resulting from design deficiencies in power supplies for safety related DC motor operated valves have recently been identified.

The NRC Information Notice No. 88-72 entitled, " Inadequacies in the Design of DC Motor Operated Valves", was issued to inform utilities of the potential problems in the design of dc motor operated valves, it was expected that recipients would review the NRC Information Notice for applicability to their facilities and consider actions as appropriate. At the time of the NRC Special Electrical Team Inspection, PECo had not completed its review of NRC Information Notice No. 88-72.

More recently the NRC issued NRC Information Notice No. 89-11 entitled, " Failure of DC Motor Operated Valves to Develop Rated Torque Because of improper Cable Sizing."

Subsequent to the NRC Special Electrical Team inspection, N'iC Information Notice No. 89-16 entitled " Excessive Voltage Drop in DC Systems" nas issued. This notice extends the concern of adequate voltage beyond DC motor operated valves.

PECO RESPONSE INPO SER 25-88 is related to NRC Information Notice No. 88-72. Both of these documents and NRC Information Notice No. 89-16 were received and are being tracked in the Operating Experience Assessment Program.

The PECo position on issues of INPO SER 25-88 and NRC Information Notice 88-72 have been defined. It has been determined that a design review of dc motor operated valves is required and includes the following activities:

A. Confirmation of the electrical design of MOV's in PBAPS Unit 2.

B. Confirmation of the electrical design of MOV' sin PBAPS Unit 3.

To support the Unit 2 restart activities, item A has been evaluated as described below. Item B will be completed prior to restart of the Unit 3. i To evaluate the electrical design of dc motor operated valves in the PBAPS Unit 2, calculations were performed to address the capability of each valve to accomplish the required safety function under the minimum anticipated dc power distribution i system voltage combined with elevated temperatures resulting from postulated design basis accidents.

1 This evaluation, which incorporated the concerns presented in NRC Information Notice 89-16, indicated acceptable operability of dc MOV's with the exception of the following valves:

MO-2-23-014 MO-2-23-019 MO-2-23-020 For these valves the results of the calculations indicate that the motors, which utilize 1

l step starting resistors, may not actuate their associated valves immediately under the applicable limiting case system and environmental conditions. It was concluded 1

. . . Attachrnent 1 q u

that the installed resistors do not allow the motors to draw sufficient starting -l current and thus the motors may not produce the torque required for timely valve actuation.

To resolve this potential problem a modification to remove the starting resistors from the motor circuits of these valves will be implemented prior to the PB APS, Unit 2 restart. A similar evaluation will be performed for the dc MOV's in Unit 3. Any required modifications will be implemented prior to Unit 3 restart.

PECo will formally address NRC Information Notice No. 89-11 as part of our Operating Experience Assessment Program. However, our existing evaluations-indicate that the PBAPS Unit 2 design, with the modifications mentioned above, does provide the required torque for operability of DC MOV's.

For NRC Information Notice 89-16 a program will be established and calculations performed to confirm voltage adequacy at equipment terminals for non - MOV Class 1E equipment. The results of this program will demonstrate that the voltage drop in power circuits will in no case result in the terminal voltage less than required for equipment operation. Calculations for the operation of dc powered equipment will be prepared to confirm operability of the equipment during design basis conditions.

The cable voltage drop analysir for dc control circuits will include the inrush current of any connected devices, circuit totallength accounting for the cumulative effects of cable cor$ductors, circuit resistance and the device minimum vo!tage rating. The calculations for Unit 2 will be completed in 1989. The Unit 3 calculations will be completed in 1990.

The anticipated impact of this evaluation on PBAPS Unit 2 is considered minimal and does not present a constraint for restart as:

1)

The batteries have been shown to have substantial positive margin, This margin equates to a higher minimum battery terminal voitage throughout the battery duty cycle.

2) Cables at PB APS have been sized in accordance with ICEA and NEC criteria providing margin for concerns such as voltage drop while meeting equipment minimum voltage ratings, and

3) No dc equipment failures have been identified over the operating history that are attributable to insufficient terminal voltage.

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( Attachment 2 TITLE: QUESTIONABLE MARGIN OF 28 AND 2D BATTERY I

PECO INTERPRETATION OF CONCERN Site Question for Engineering SOE P-50080, which is the most recent evaluation of

< the capacity of batteries 2BD001 and 2DD001, concludes that these batteries have a design margin and aging factor of 1.0 and 1.15, respectively. IEEE Standard 485 recommends a design margin of 1.15 and an aging factor of 1.25 when sizing a new battery. Therefore, it is not obvious that battenes 2BD001 and 2DD001 have sufficient capacity.

PECO RESPONSE A new calculation has been prepared to evaluate the margin between the rated capacity of the batteries and the design load profile. This calculation uses the existing calculations as a basis for the design load profile and includes an allowance of 5% for uncertainty in the magnitude of individualioads presently not confirmed by field walkdown. The calculation evaluates the margin for both a 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> duty cycle. The results are as follows:

Percent Margin Percent Margin for 2 Hour for 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> Battery Duty Cycle Duty Cycle 2AD001 104 97 2BD001 52 8 2CD001 104 97 2DD001 52 8 This new calculation also evaluates the consequences of removing the starting resistors for various dc motor operated valve motors to resolve concerns related to NRC Information Notice 88-72. The increased inrush current has an impact on the battery load profile, reducing the available margin.

PECo has decided to adopt a design load profile of less than four hours, cor sistent with typical utility practice. Since the diesels start in approximately 10 seconds and restore power to the 480V auxiliaries including the battery chargers within 16 seconds after loss of offsite power,the batteries are only required to provide power for approximately 16 seconds. Thus,the typical utility practice of using a design load profile with a duration of two hours 3rovides a significant degree of margin.

The results of the margin calculations, witi the increased inrush current due to removing starting resistors in response to NRC Information Notice 88-72, are as follows:

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c Attachment 3 Percent Margin for 2 Hour

' Battery Duty Cycle 2AD001 104 2BD001 21 2CD001 104 2DD001 21 IEEE Standard 485-1983, which is applicable for sizing a new battery, recommends a design factor of 1.15 and an aging factor of 1.25, for a total margin of 44%.

However, IEEE Standard 450-1980, which is applicable for the ongoing assessment of available margin, implies in Section 6.6, " Service Test," that a battery is acceptable if it passes a service test which duplicates the design battery duty cycle, as this demonstrates that the battery meets the design requirements of the system.

A battery is acceptable for continued use when the design load profile changes, provided that a margin exists between the capacity of existing battery and that required to meet the revised load profile.

The battery discharge tests performed in 1987 demonstrated that the tested capacity of both batteries exceeded their rated capacity. Since battery capacity normally decreases only a few percent during the first 10 years of battery life, PECo concludes that the present battery capacity is still in excess of rated capacity.

Therefore, PECo concludes thatthe existing Unit 2 batteries are adequate for the restart of Peach Bottom Unit 2 without further analysis or testing. Due to the similarity of system design between Unit 2 and 3, confirmation of the adequacy of the Unit 3 battery is expected. Nonetheless, a similar evaluation of the Unit 3 -

batteries will be completed prior to the restart of Unit 3.

PECo is proceeding to prepare new base line calculations to define the loading profile for each Class 1E battery in Units 2 and 3. These calculations will be based on field walkdown data to establish the load from individual components and will be used for load management control to demonstrate that each battery is suitable for continued use in accordance with IEEE Standard 450. These calculations will be updated and formally revised on a regular basis to account for load changes as the result of plant modifications and plant operating procedure chanc es. Walkdown data is presently being collected, and preparation of these design aasis calculations for Unit 2 will be completed in 1989, and the calculations for Unit 3 will be completed in 1990.

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Attachmant 3

. TITLE: UNDERRATED FUSES PECO INTERPRETATION OF CONCERN _

NRC Information Notice 84-65 " Underrated fuses which may adversely affect operation of essential electrical equipment" was issued on August 6,1984. This notice identified the Gould-Shawmut TR-R100 fuses as having a~ dc voltage rating of lessthan 250 volts.

During the recent NRC Special ElectricalTeam inspection at the Peach Bottom Atomic Power Station Units 2 & 3, the following Gould -Shawmut TR-R100 fuses L . were identified in 250Vdc safety related applications:

1 Bus: 20D11-

. Circuit 29-1100'

_ RHR Pump Suction Cooling Valve MO-2-10-017 Bus: 30D011 -

Circuit 29-1100 -

RHR Pump Suction -

Cooling Valve MO-3-10-017

' PECO RESPONSE in response to the concern of TR-R100 fuses installed in safety related 250VDC applications, Non Conformance Reports (NCR's) P89050-216 and P89111-216 were generated to resolve this issue at PBAPS Units 2 & 3. These NCR's have been dispositioned to replace the TR-R100 Gould - Shawmut fuses with TR-5100 Gould - Shawmut fuses. The installation of the safety related TR-5100 fuse

. in MCC 20D11 (30D11) to replace the existing TR-R100 fuses will be completed prior to restart of each unit.

.The specifications for Gould - ShawmutTR-R and TR-5 fuses are described below:

Model TR-R TR-5 Ampere rating 100a 100a RK5 RK5~

Class Sym. Short Circuit Rating 200 KAIC 200 KAIC UL Listed No Yes DC Voltage Rating (Per UL 198L) 200VDC 600VDC The application of the TR-5100 fuse will provide a 600VDC rating while maintaining coordination with the upstream protective device. Calculation EE-7 Section E6 has l been revised to document circuit coordination with the new TR-5100 fuse.

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(:( ". < 4, Attachment 3 l

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? A design review of the 125/250VDC power system was performed that concludedi '

the ratings of the remaining fuses are appropriate for the design application. A

walkdown of the subject fuses has confirmed that the installed fuses match the

. design drawings.  ;

j. An engineering memorandum will be issued to electrical engineering and design :.

. personnel to clarify the significance of AC and DC voltage ratings of DC )

components. Special consideration for voltage the rating of fuses will be 1 highlighted. This memo will.be issued prior to restart of Unit 2.

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Attachm:nt 4 TITLE: WRONG TYPE OF FUSES PECO INTERPRETATION OF CONCERN A. The dc control fuses installed in 250 Vdc MCC 20D11 compartment 29-1112 and 29-1121 are 10A while other MCC compartments have 6A fuses in their j control circuits. The adequacy of this situation needs to be evaluated.

B.1 Drawings E-26 and E-27 identify the fuses in fuse box 20D19 and 30D19 as Bussman Class RK5 type FRN,250 Vac. The installed fuses are Gould l

Shawmut Class RKS, type TR-R 250 Vac. The adequacy of the Gould Shawmut fuses needs to be evaluated.

B.2 Circuits 29-BD30604 and 29-BD30605 have 30A type "NON" and "KON" fuses installed while drawing E-26 indicates a type "FRN" fuse should be used. This discrepancy needs to be evaluated.

PECO RESPONSE A. Inconsistency of Control Fuse Sizes in 250 Vdc MCC:

The primary purpose of a control fuse is to provide short circuit protection.

Control fuses are sized such that the interrupting rating is not less than the maximum short circuit current of the control circuit. Although different from the other control circuit fuses in the MCC 20D11, the existing 10A fuses for compartments 29-1112 and 29-1121 provide adequate short circuit protection.

To provide consistency of control circuit protection inside the Unit 2 MCC's, the 10A fuses will be changed to 6A fast acting Bussman Limitron type fuses.

This work will be accomplished prior to restart of Unit 2. Any corresponding changes required in the Unit 3 MCC will be accomplished prior to restart of that unit.

B. Installed fuse type inconsistent with design documents:

1. An engineering evaluation indicated the time-current characteristics of the Gould-Shawmut TR-R fuse was similar to the Bussman FRN and resulted in no change to the electrical coordination.

Non Conformance Report (NCR) P899025-312 was initiated and I

dispositioned to reflect the installed Gould-Shawmut TR-R fuses on single line drawings, E-26, sheet 1, and E-27, sheet 1. Calculation EE-7, l Section E6 was also updated to reflect the time-current characteristics for the type TR-R fuses. This discrepancy was identified and documented by PECo prior to the NRC Special Electrical Team inspection. The related documentation has been revised and issued.

2. An engineering evaluation was performed and showed that the installed 30A "NON" and "KON" fuses provide electrical system coordination with the 200A type FRN supply fuse in 125 Vdc panel 2BD306. However,to provide consistency with the design documents, the "NON" and "KON" fuses are being replaced with "FRN" type fuses 1

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Attachment 4.

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as shown on drawing E-26, Sheet 1. This replacement will be completed prior to restart of PB APS Unit 2.

A walkdown of the Unit 2125/250 Vdc system has confirmed that no l :-

' additional discrepancies exist between the single line drawings and the

' installed fuses. A similar walkdown for Unit 3 will be done pnor to restart of Unit 3. Any identiited Unit 3 fuse discrepancies will be resolved prior to l_

!- Unit 3 restart.

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Attachment 5 f

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-TITLE: LACK OF SURVEILLANCE PECO INTERPRETATION OF CONCERN The PBAPS 125V battery charger maintenance procedure M-57.4 does not include maintenance for the AC and DC breakers internal to the battery charger. Is this exclusion of breakers from Preventative Maintenance (PM) consistent with the PBAPS commitment and program for Preventative Maintenance for equipment and components or, is it an oversight where a vendor recommended maintenance has not been included in the plant PM procedure?

If the exclusion of the breakers from the plant PM is an oversight,is this an isolated deviation from the program or a result of programmatic weakness thatwould cause recurrence of a similar nature if not corrected?

Relay 27FF in the Diesel Generator System was not included in the yearly PM or Surveillance Testing. Is this calibration required to ensure operability or per vendor recommendation and thus not included in PM or ST by an oversight?. lf it is an oversight,is it an isolated case, or the result of a weakness in the PM program that may cause a recurrence of a similar nature?

PECO RESPONSE ~

The surveillance activity of safety related components such as the breakers and relays is based on vendor recommendations given in Technical Manuals and EQ documentation.

To assure adequate surveillance is being maintained a detailed review of the present PECo position on Equipment Surveillance, Generic Letter 83-28 actions, and other identified concerns was performed. The results of the review are summarized below:

1) Aspects of Generic Letter 83-28 addressing utility actions on vendor information for safety-related components have been fully responded to by PECo.

2) PECo commitments of Preventative Maintenance and Surveillance in areas identified in NRC Inspection Report 86-25 have been fulfilled. The Diesel Generator Room Supply Fans and Battery Room Exhaust Fans have been included in the Preventative Maintenance Program.

3) The Vendor Manual Update Program was completed in 1988, including the i revision of affected procedures.

4) PBAPS has a committment to the Commonwealth of Pa.to have a program defined for review, approval, and control of vendor manuals prior to restart of Unit 2.

5) Vendor manuals reviewed during the preparation of this response were found '

controlled and up-to-date.

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Attachment '5 L

6) . Breaker and relay maintenance was included in the Plant Program where .

' required by the vendor.

l 'The AC and DC breakers identified during the inspection are installed in each battery charger. The basic function of the circuit breakers is to serve as a disconnect switch to isolate the battery charger from the AC and DC systems. The breakers are not used as protective devices either for thermal overload or short circuit current.

The circuit breakers as designed are adequate to achieve their functions in the -

battery charger without routine calibration. Exercising the breakers during maintenance of the battery charger is sufficient to provide assurance of their intended function. The confirmation of equ,ipmentisolation will be included in the PM program for each the battery charger pnor to Unit 2 restart.

Relay 27FF is a loss of field flashing voltage alarm relay, provided for each diesel generator. Relay 27FF has been provided to detect a loss of the 125Vdc supply voltage to the exciter and to annunciate the loss of voltage after a 20 second time delay. Improper relay operation will not prevent the diesel generators from starting or performing their safety function. The 27FF relays will be added to the PM program associated with each diesel generator and will be functionally tested prior to Unit 2 restart.

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' Attachment 6 L

L TITLE: QUESTIONABLE 13.8 KV SWITCHGEAR INTERRUPTING CAPACITY PECO INTERPRETATION OF CONCERN The NRC reviewed the PBAPS Calculation EE-7, Subsection E2 "AC System Fault Calculation" and raised a concern regarding the low margin in the 13.8kv circuit

- breaker interrupting duty. The margin was 1.3% as shown in the calculation.

The NRC also questioned the limiting case electrical distribution bus configuration assumed in the subject calculation. This case assumed "the recirc pump M-G set tripped, the auxiliary buses fast transferred to one offsite power source, and cooling towers D & E tripped". The NRC requested comparison of this case with the plant startup configuration of two recirculation pump M-G sets running on two offsite power sources before transferring to the one auxiliary system. It was pointed out to the NRC that the subject calculation is conservative as it did not include factors such as cable impedance. The NRC requested an evaluation of the conservatism in the

_' calculation .

PECO RESPONSE

" AC System Fault Calculation" was prepared for the Appendix R Breaker / Relay Coordination Study in 1986. The 1.3% margin of 13.8kv breaker interrupting capacity is based on ANSI standard C37.0101979.

The calculation has been revised to include the operating configuration case of two' recirculation pump M-G sets running on offsite sources. The margin obtained is 11.2% as compared with 1.3%. This confirms that the existing selection of the worst case operating condition was correct.

The calculation has also been updated to quantify the conservatism resulting from exclusion of the 13.8kv cable impedance. Accounting for cable impedance, the margin increases from 1.3% to 13.4%.

Therefore,it is concluded that the PBAPS Units 2 & 3 electrical system has adequate short circuit withstanding capability, as proven by the updated calculations.

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Attachment 7 TITLE: ADEOUACY OF MCC FEEDER CABLE AMPACITY VERSUS BREAKER SETTINGS l

j PECO INTERPRETATION OF CONCERN Calculation EE-7, Subsection E-3, Page 5, notes that the long time delay settings of certain breakers feeding the MCC's exceed the ampacity of the feeder cables. As a 4 result, the possibility exists that without protective action, these cables may become l overloaded, and therefore overheated.

Calculation EE-7, Subsection E-3, documents breaker coordination. However,it does i not document the MCC feeder cable ampacities exactly, nor does it document the design load on the MCC feeders. The determination of the adequacy of the breaker settings for equipment and cable protection requires additional documentation.

PECO RESPONSE PECo has maintained the design philosophy that breakers feeding MCC's should be setto avoid the possibilty of inadvertent tripping. PECo considers the continued operation of Class 1E systems is more critical than preventing minor short duration cable overloading.

Feeder cables to individual loads require overcurrent protection,in addition to fault protection, since a com aonent failure or individual fault could result in over%ading of these dedicated feec er cables. However, cables to MCC's are not subject to the same type of overloads as the feeders to individual loads. The MCC feeder cables require short circuit protection, but the overload protection is controlled by the design process which limits the amount of load applied, rather than from breaker overcurrent arotection settings. Therefore,the long time element of the MCC feeder breaiersis not essential for cable overload protection. However,the continued operation of the MCC is essential for plant safety in the event of a design basis accident. Therefore, it is more prudent to set the long time delay element at a relatively high level to avoid the possibility of inadvertent tripping.

The cables feeding each MCC are sized on the basis of the anticipated running load for the MCC. In response to the NRC Special Electrical Team Inspection concern, a reevaluation has been performed which confirms that the feeder cable ampacity exceeds 125% of the anticipated worst case running load on the MCC. Therefore, there is no need to increase the size of any of the feeder cables.

PECo therefore concludes that the design, as it stands, is adequate and imposes no constraint on the restart of either Unit 2 or Unit 3.

PECo will revise calculation EE-7, Subsection E-3, to document the design philosophy for MCC feeder long time cable protection and to confirm the adequacy of the cable ampacity for the anticipated coincidental loading.

PECo will review the feasibility and cost benefit of providing an improved design for MCC feeder cable overcurrent protection. The review will be completed during the next refuel cycle following restart of Unit 2 and 3.

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Attachment 8 4

i TITLE: DIESEL GENERATOR LOAD ANALYSIS PECO INTERPRETATION OF CONCERN The NRC Special Electrical Inspection Team identified inconsistencies between the emergency diesel generator loading calculation and the information presented in the FSAR Table 8.5.2.

Based on these inconsistencies the adequacy of the diesel generator to supply power during a plant DB A and shutdown conditions was questioned. Specifically the following concerns were identified:

1. Appropriate conversion of horsepower to KW loading of major individualloads.

2. Determination of the worst case dieselloading based on the conditions described in the FSAR Table 8.5.2.

3. Confirmation that the diesel generators are capable of supplying the identified worst case load for the required period of operation.

PECO RESPONSE A review of the Diesel Generator and Emergency Bus Loading tables of the UFSAR show that the highest load occurs on DG El during the 10-60 minute time interval of the DG loading cycle.

j The total load on DG El during this time interval consists of two 4 kV loads (one RHR I

pump and one Core Spray pump) and two 480Vioad groups each of which is supplied by a 500 KVA load center transformer.

The RHR pump motor load has been conservatively calculated to be 1604 KW based on the motor rating of 2000 hp and a fullload efficiency of 93%. This is the value used for the RHR pump motor in the load tabulation of the Voltage Regulation Study, dated January 1989. This value is considered conservative, as demonstrated by the pump test curves. These curves indicate a pump runout condition of about 12,000 GPM rec uiring 1900 BHP, while the design rated f!nw of 10,000 GPM requires l 1,800 BHP whic1 equates to a 1,444 KW load at 93% efficiency.

The second 4 kV load on DG E1 is the core spray pump. The nameplate values of 600

' horsepower and 93% efficiency result in a 481 KW design load.

Loads at 480V and below have been reviewed against the loads used in the Voltage Regulation Study, the single line diagrams, and schematics to determine

! conservative load values.

Since the major loads have been calculated on the basis of rated horsepower and nameplate efficiency, the potential for inadvertent overloading has been avoided as described in Section 2 of Generic Letter 88-15, power factor misapplication.

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l Attachment 8 The diesel generator is not operated for base load generation, and is only required

. for sustained operation following a LOOP /LOCA and prior to restoration of offsite power. Therefore the 200 hour0.00231 days <br />0.0556 hours <br />3.306878e-4 weeks <br />7.61e-5 months <br /> rating is applicable. ,

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. The total KW load, assuming conservative loadings as described above is 3,006 KW for DG E1. This load is within the 3,100 KW,200 hour0.00231 days <br />0.0556 hours <br />3.306878e-4 weeks <br />7.61e-5 months <br /> rating of the unit. It is therefore concluded that the diesel generators are adequately rated to support

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DBA loading for Unit 2 and emergency shutdown of Unit 3.

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