ML19260A135

Tech Spec Change Request 60 Supporting Licensee Request to Change App a of License DPR-50.Change Concerns Emergency Power Systems Per NRC 770603 Request for Comparison of Current Design W/Nrc Positions.Certificate of Svc Encl

ML19260A135
Person / Time
Site:	Three Mile Island
Issue date:	08/19/1977
From:	Arnold R METROPOLITAN EDISON CO.
To:
Shared Package
ML19260A133	List: ML19260A132 ML19260A135
References
GQL-1145, NUDOCS 7910290750
Download: ML19260A135 (11)

Text

'

METROPOLITMi EDISCII COMPANY JERSEY CENTRAL PO'n'ER & LIGHT COMPMIY AND PENNSYLVMIIA ELECTRIC COMPMIY

, THREE MILE ISLAND NUCLEAR STATION UNIT 1 Operating License No. DPR-50 Docket No. 50-289 Technical Scecification Change Recuest No. 60 This Technical Specification Change Request is submitted in support of Licensee's request to change Appendix A to Operating License No. DPR-50 for Three Mile Island :Iuclear Station Unit 1. As a part of this request, proposed replacement pages for Appendix A are also included.

METROPOLITMI EDISON COMPANY f .

By! /

/ Vice President

/

J Sworn and subscribed to me this $! day of , 1977 Notary Public e.gTARY D'j N .

Reacmg. Sera? O r~v i My Comm ssien baats

• R '"

1480 165 3 910 2907f0

UNITED STATES OF AMERICA NUCLEAR REGULATORY COMiISSION IN THE MATTER OF DOCKIT NO. 50-289 LICENSE NO. DFR-50 METROPOLITAN EDISON COMPANY This is to certify that a copy of Technical Specification Change Request No. 60 t,e Appendix A of the Operating License for Three Mile Island Nuclear Station i! nit 1, has, en the date given belov, bee' filed with the U. S. Nuclear Regulatory Cc: mission and been served on the chief executives of Lcndonderry Township, Dauphin County, Pennsylvania and Dauphin County, Pennsylvania by deposit in the United States mail, addressed as follows:

Mr. Weldon B. Arehart Mr. Harry B. Reese, Jr.

Board of Supervisors of Board of County Commissioners Londenderry Township of Dauphin County R. D. #1, Geyers Church Road Dauphin County Court House Middletown, Pennsylvania 17057 Harrisburg, Pennsylvania 17120 METROPOLI"'AN EDISON CCIGANY l

By , ' / h /

'Vi'ce President Dated: Aum:st 10 lo77 1480 166

Three Mile Island Nuclear Station, Unit 1 Operating License No. DFB-50 Docket No. 50-289 Technical Specifiestion Change Recuest No. 60 The licensee requests that the attached revised pages replace pages 3-32, 3-37, h-h6, and h-h7 of the existing Technical Specifications, Appendix A.

Reasons Por Change Reauest -

This change request is to comply with the Co==ission's June 3,1977 letter requesting a comparison of our current design of the emergency power systems at TMI-l with the Staff Positions.

Safety Analysis Justifying Chance Position 1:

As requested in your letter of June 3,197', below is our analysis to show TMI-l has eqaivalent capabilities and protective fes'. ares to the Staff Position on second level protection.

The Cen=ission required a second level of voltage protection fcr the onsite power system be provided in order to prevent a sustained degradation of the offsite power syste='s voltage from causing the failure of redundant safety-related electrical equipment.

Metropolitan Idison has determined that this requirement is not necessary for TMI-1 based on the following:

The Class 1E electrical systes at TMI-l has undervoltage trip relaying protection on all safety-related electrical buses (the h160 volt E.S.

buses ID and 1E, the h80 volt buses IP, 1R, 1S and 1T). The undervoltage trip setpoints are:

Bus Setnoints b kv. 3534 volts h80 v. h10 volts The original and present basis for the undervoltage trip setpoints is to maintain the bus voltage above the =inimus motor starting voltage for safety equipment. These setpoints were deter =ined after reviewing the various bus voltage levels and the required mini =u= motor starting voltage. The 353h volt trip setting on the h kv bus corresponds to a 206 kv value for the off-site power system. Therefore, any degraded voltage level below a 206 kv grid vo]tage vould result in the automatic transfer to the onsite power source.

1480 167

The Cc==ission vas concerned with the operation of electrical safety equipment between this trip value and the nominal grid voltage level of 232 kv. This second level of undervoltage relaying would be set somewhere in this range, such that, if the grid voltage vould degrade to a value below nominal (232 kv) but above the existing undervoltage, (206 kv), after a preset time period, the second level relay would be activated and automatically transfer to the on-site power source. This is not necessary at TMI-1 because the safety-related electrical equipment was designed to operate within this degraded condition.

Tects conducted by IMI-l personnel on starters /contactors supplying power to three phase h80 v. ES equipment have confirmed that they operate satisfactorily to a voltage of 3Sh volts. The h kv equipment (E.S. motors) are controlled by circuitry utilizing 125 V.D.C. and therefore, would not be affected by any sustained degraded voltage level.

An analysis of plant operation and equipment failure during a degraded grid voltage was performed. This analysis pointed out that no proble=s von'.d be encountered during a degraded grid voltage condition, and the degradation of grid voltage to that corresponding to the undervoltage trip setpoint was an extre=ely unlikely situation. As a continuation of this analysis, a study was done to deter =ine the probability of occurrence of a degraded grid voltage below 215 kv. The probability of the contingencies that could result in this condition are in the 10 7 to 10 10 range. Therefore, it is concluded that no modifications to the Class lE distribution system at TMI-l is required.

Position 2:

The current undervoltage relaying scheme for all E.S. buses have the Cotsissiun'c t position incorporated. The E.S. buses undervoltage relays initiate the ? cad shedding. As soca as the diesel generator breaker closes in, an auxiliary contact opens preventing the undervoltage relaying from initiating the load shedding. If the diesel generator breaker should trip, the auxiliary contact vill close, reinstating the load shedding feature. Therefore, no modifications are necessary for Position 2.

~

Position 3:

TMI-l surveillance procedures currently perform portions of the Commission requirements. Metropolitan Edison vill rewrite the surveillance procedure which delineates this testing to fulfill the requirements of demonstrating the diesel generator operable while simulating a loss of off-site power in conjunction with a safe +y injection actuation test signal.

This vill verify that on interruption of the onsite source (diesel generator) the loa 7.4 are shed from the emergency buses, in accordance with design requirenents and that subsequent loading of the onsite source is through the load sequencer.

This vill be accomplished by:

1480 168

1. Opening the offsite power source breaker to.the emergency bus si=ulating loss of offsite power. It vill be verified that the proper loads are shed from the emergency buses.

2. Concurrently, an ES signal vill be activated. It will then be verified that the diesel generator starts and the emergency buses are loaded in their proper sequence. .

3 After operating for 5 minutes, the diesel generator breaker vill be tripped, verifying that the leads are again shed,

b. The diesel generator breaker vill again close. There vill be verification that the auto-connected e=ergency loads are energized through the load sequencer and the diesel operates loaded for 5 minutes.

r 1480 169 4

TABLE 3.5-1 Continued .

INSTRUMENTS OPERATION CONDITIONS Functional Unit (A) (B) (C)

Engineered Safeguards Minimum Operable Minimum Degree of Operator Action if Conditions Analog Channels Hedundancy of Column A and B cannot be met (a)

3. Reactor Building Isolation.

and Reactor Building Cooling System g

a. Reactor Building 14 puig Instrument Channel 2 1 llot Shutdown

b. Manual Pushbutton 2 1 llot Shutdown

(") If minimum conditions are not met within 2fs hours, the unit shall then be placed in a cold shutdown condition.

(b) Also initiates Low Pressure injection.

14 . Reactor Building Spray System

a. Henetor Building 30 psig Instrument Channel 2(b) 1  !!ot Shutdown

b. Spray Pump Manual '

Switches (c) 2 1 Ilot Shutdown (3) If minimum conditions are not met within 214 hours0.00248 days <br />0.0594 hours <br />3.53836e-4 weeks <br />8.1427e-5 months <br />, the unit shall then be placed in a cold shutdown condition.

C (b) Two out of three switches in each actuation channel operable.

(c) Spray valves opened by manual pushbutton listed in item 3 above.

O

TABLE 3.5-1 Continued INSTHUMENTS OPEllATION CONDITIONS Functional Uiit (A) (B) (C) 5 4.16 Kv Emergency Buy Undervoltage Relays (d) 2/ Bus - 1/ Bus (e)

(d) Total no. of channels - 3/ Bus g (e) With the number of Operable Channels one less than the total number of channels operation may proceed until performance of the next required Channel Functional Test provided the inoperable channel is placed in the trip condition within 2h hours.

Y M

P O

M CD CD

353 ENGINEERED SAFEGUARDS PROTECTI0h SYSTEM ACTUATION SETPOINTS Apulicability This specification applies to the engineered safeguards protection system actuation setpoints.

Objective To provide for automatic initiation of the engineered safeguards protection system in the event of a breach of Reactor Coolant System integrity.

Specification .

3 5.3.1 The engineered safeguards protection system actuation setpoints and permissible bypasses shall be as follows:

Initiating Sienal Function Setnoint High Beac+ Building Reactor Building Spray 1 30 psig Pressure (o1 High-Pressure Injection i h psig Low-Pressure Injection i k psig Start Reactor Building Cooling & Reactor Building Isolation i h psig Low Reactor Coolant High Pressure Injection >150 2) and E500 3) p31g System Pressure Lov Pressure Injection >150Q(2) and E500(3)psig h.16 kv E.S. Buses Switch to Onsite Power Undervoltage Source and Load Shedding 353h volts (h)

(Loss of Offsite Power or Voltage) egraded 5

(1) May be bypassed for reactor building leak rate test.

(2) May be bypassed below 1650 psig and is autome.tically reinstated above 1650 psig.

(3) May be bypassed belov 900 psig and is automatically reinstated above 900 psig.

( ) Allowable values - 353h is the nominal setpoint. 3h23 is the minimum allowed setting.

(3) The undervoltage relays (0.E. 12AV53K1A) have characteristic time -

Voltage Curves, when the voltage is reduced to 2995v, the relay will trip in

<T.15 sec. 1480 172 3-37

Bases High Reactor Building Pressure The baais for the 30 psig and h psig setpoints for the high pressure signal is to establish a setting which would be reached in adequate time such that protection is provided for the entire spectrum of break sizes and is far enough above normal containment internal pressures to prevent spurious initiation.

Lov Reactor Coolant System Pressure The basis for the 1500 and 500 psig low reactor coolant pressure setpoint for high and low pressure injection initiation is to establish a value which is high enough such that protection is provided for the entire spectrum of break sizes and is far enough below nor=al operating pressure to prevent spurious initiation.

t 1480 173 3-37a

h.6 DERGENCY POWER SYSTDI PERIODIC TESTS Apolicability Applies to periodic testing and surveillance requirement of the e=ergency power system.

Objective To verify that the emergency power system vill respond pro =ptly and properly when required. -

Specification The following tests and surveillance shall te performed as stated:

h.6.1 Diesel Generators

a. Manually-initiated start of the diesel generator, followed by manual synchronization with other power sources and assumption of load by the diesel generator up to the nameplate rating (3000 kv). This test vill be conducted every month on each diesel generator. Normal plant operation vill not be affected.

b. Automatic start of each diesel generator and restoration to operation of particular vital equipment, initiated by an actual loss of normal a-c station service power supply together with a simulated engineered safeguards actuation signal. This test vill be conducted during reactor shutdown for refueling to assure that the diesel-generator vill start assuming load in ten seconds and assume the load of all safeguards equipment listed in 4.51.lb within 60 seconds after the initial starting signal.

This test vill be conducted to verify the followind -

(1) Upon loss of normal a-c station service power supply the de-energization of the emergency buses and load shedding occurs.

(2) The diesel starts from ambient conditions on the auto-start signal, energizes the emergency buses with permanently connected loads, energizes the auto-connected emergency loads through the load sequencer and operates for 5 minutes.

(3) On interruption of the onsite source, the loads are shed from the emergency buses in accordance with design requirements.

That on reconnection with the onsite source, the emergency buses are energized with permanently connected loads, the auto-connected emergency loads are energized through the load sequencer and the diesel generator operates for 5 minutes.

1480 174 h-L6

2. Each diesel generator shall be given an inspection at least annually in accordance with the manufacturer's reco==endations for this class of stand-by service.

h.6.2 Station Batteries

a. The voltage, specific gravity, and liquid level of each cell' vill be =easured and recorded monthly.

b. The voltage and specific gravity of a pilot cell vill be =easured and recorded weekly. .

c. Each ti=e data are recorded, new data shall be compared with old to detect signs of abuse or deterioration.

d. The battery will be subjected to a load test at a frequency not to exceed refueling periods. The battery voltage as a function of time vill be monitored to establish that the battery performs as expected during this load test.

Bases The tests specified are designed to de=onstrate that one diesel-generator vill provide power for operation of safeguards equipment. They also assure that the e=crgency generator control syste= and the control syste=s for the safeguards equipment vill function automatically in the event of a loss of normal a-c station service power or upon the receipt of an engineered safeguards actuation signal. The testing frequency specified is intended to identify and permit correction of any =echanical or electrical deficiency before it can result in a syste= failure. The fuel oil supply, starting circuits, and controls are continuously monitored and any faults are alarmed and indicated. An abnormal condition in these systems would be signaled without having to place the diesel generators on test.

Precipitous failure of the station battery is extremely unlikely. The surveillance specified is that thich has been de=onstrated over the years to provide an indication of a cell becoming unserviceable long before it fails.

R EFERENCE (1) FSAP, Section 8.2 1480 175 h h7