ML20247K408

Proposed Tech Specs,Revising Section 3/4.9 to Incorporate Reactor Protection Sys Electrical Protection Assemblies

ML20247K408
Person / Time
Site:	Pilgrim
Issue date:	09/11/1989
From:	BOSTON EDISON CO.
To:
Shared Package
ML20247K399	List: BECO-89-136, Application for Amend to License DPR-35,revising Tech Spec Section 3/4.9 to Incorporate Reactor Protection Sys Electrical Protection Assemblies ML20247K408
References
NUDOCS 8909210152
Download: ML20247K408 (6)

Text

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ATTACHMENT B 8909210152 890911 PDR ADOCK 05000293 P PDC

LIMJTING CONDITIONS FOR OPERAT10N 9JRVEJLLANCE REQUIREMENTS 3.9.A AUXILIARY ELECTRICAL EOUIPMENT 4.9.A AUXILIARY ELECTRICAL EQUIPHENT (Cont'd) SURVEILLANCE (Cont'd)

4. 4160 volt buses A5 and A6 are d. Once a month the quantity of energized and the associated 480 diesel fuel available shall '

volt buses are energized. be logged.

i

5. The station and switchyard 125 and e. Once a month a sainple of 250 volt batteries are operable. diesel fuel shall be checked Each battery shall have an for quality in accordance operable battery charger, with ASTM D4057-81 or D4177-82. The quality shall

6. Emergency Bus Degraded Voltage be within the acceptable Annunciation System as specified limits specified in Yanie 1 '

in Table 3.2.B.1 is operable, of ASTM D975-81 atd logged.

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7. Specification 2. Station and Switchyard Batteries Two redundant RPS Electrical a. Every week the specific Protection Assemblies (EPAs) shall gravity, the voltage and l be operable at all times on both temperature of the pilot cell inservice power supplies. and overall battery voltage shall be measured and logged.

Action

b. Every three months the

a. With one EPA on an inservice measurements shall be made of power supply inoperable, voltage of each cell to continued operation is nearest 0.1 volt, specific permissible provided that the gravity of each cell, and EPA is returned to operable temperature of every fifth status or power is transferred cell. These measurements to a source with two operable shall be logged.

EPAs within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. If this requirement cannot be met, trip c. Once each operating cycle, the power source. the stated batteries shall be subjected to a rated load

b. With both RPS EPAs found to be discharge test. The specific l

inoperable on an inservice gravity and voltage of each power supply, continued cell shall be determined operation is permissible, after the discharge and l provided at least one EPA is logged.

restored to operable status or power is transferred to a 3. Emergency 4160V Buses AS-A6 source with at least one Degraded Voltage Annunciation operable EPA within 30 System.

minutes. If this requirement cannot be met, trip the power a. Once each operating cycle, source. calibrate the alarm sensor.

NOTE: Only applicable if tripping the b. Once each 31 days perform a power source would not result in a channel functional test on scram. the alarm system.

Revision 1 Amendment No. 195

il5LTINJ_ CONDITION FOR OPERATION SURVEILLANCE REQUIREMENTS

~

3.9.B Operation with Inonerable 4.9.A Auxiliary Electrical Eauioment Eauipment Surveillance (Cont'd)

Whenever the reactor is in Run c. In the event the alarm system ,

Mode or Startup Mode with the is determined inoperable  ;

reactor not in a Cold Condition, under 3.b above, commence the availability of electric power logging safety related bus .

shall be as specified in 3.9.B.1, voltage every 30 minutes j 3.9.B.2, 3.9.B.3, 3.9.B.4, and until such time as the alarm l 3.9.B.5. is restored to operable  !

status.  !

1. From and after the date that  ;

incoming power is not available 4. RPS Electrical Protection from the startup or shutdown Assemblies )

transformer, continued reactor  !

operation is permissible under a. Each pair of redundant RPS  ;

this condition for seven days. EPAs shall be determined to i During this period, both diesel be operable at least once per generators and associated 6 months by performance of an  ;

emergency buses must be instrument functional test.  !

demonstrated to be operable,

b. Once per operating cycle.

2. From and after the date that each pair of redundant RPS incoming power is not available EPAs shall be determined to from both startup and shutdown be operable by performance of ,

transformers, continued operation an instrument calibration and '

is permissible, provided both by verifying tripping of the diesel generators and associated circuit breakers upon the i emergency buses are demonstrated simulated conditions for  ;

to be operable, all core and automatic actuation of the i containment cooling systems are protective relays within the  !

operable, reactor power level is following limits: l reduced to 257 of design and the l NRC is notified within one (1) Overvoltage 1 132 volts hour as required by 10CFR50.72. Undervoltage 1 108 volts i

, 3. From and after the date that one l of the diesel generators or associated emergency bus is made i or found to be inoperable for any '

reason, continued reactor operation is permissible in j accordance with Specification 3.5.F if Specification 3.9.A.1 and 3.9.A.2.a are satisfied.

4. From and after the date that one of the diesel generators or associated emergency buses and either the shutdown or startup transformer power source are made Revision Amendment No. 196 i

'-a

_J LIMITING CONDITION FOR 0PERATION ' SURVEILLANCE REQUIREMENTS 3.9.B Ooeration with Inocerable Eauioment (Cont'd)  ;

- 1 or fo' und to be inoperable for any .  !

reason,. continued reactor operation is permissible in accordance with Specification-3.5.F, provided either of the following conditions are

. satisfied:

a. The'startup transformer.and l both offsite'345 kV l transmission lines are  ;

available and capable of.

automatically supplying ,

auxiliary power to the emergency 4160. volt buses.  :

b. A transmission line and associated shutdown a transformer are available and  :

capable of automatically supplying auxiliary power to i the emergency 4160 volt buses.

5, From an:1 after the date that one of the 125 or 250 volt i battery systems is made or l found to be inoperable for any reason, continued reactor operation is permiss' ole '

during the succeedin, three

. days within electrical saf ety  ;

considerations, provided i repair work is initiated in l the most expeditious manner to l return the failed component to i an operable state, and l Specification 3.5.F is l l,

satisfied. ]

6. With the emergency bus voltage I

less than 3959V but above 3868V (excluding transients) .during normal operation, transfer the safety related buses to the diesel generators If grid 4 voltage continues to degrade l be in at least Hot Shutdown  ;

within the next 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> and in  !

Cold Shutdown within the j following 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> unless the i grid conditions improve. i Revision Amendment No. 197 i

fLASES (Continued) l

• 3.9  !

can be used for either 125 volt battery, (2) a 250 volt d-c back-up battery charger is supplied. Thus, on loss of normal battery charger, the back-up charger can be used. The 125 volt battery system shall have a minimum of 105 volts at the battery terminals to be considered operable. The 250 volt battery system shall have a minimum of 210 volts at the battery terminals to be considered operable.

Automatic second level undervoltage (Degraded Voltage) protection is installed on the startup transformer and is available when safety related loads are being supplied from this source. During normal operation, the unit auxiliary transformer supplies safety related buses. Automatic second level undervoltage pratection is not installed on the unit auxiliary transformer.

The Safety Bus degraded Voltage Alarm System and new Degraded Voltage Operating Procedure will be relied upon to guide Operator action to preclude operation with a degraded bus voltage condition.

Each of the two motor generator sets and the alternate power supply for the Reactor Protection System (RPS) have two Electrical Protection Assemblies (EPAs), installed in series, between the RPS 120 Volt 60Hz power source and its respective RPS bus. A random, or seismically-induced abnormal voltage or frequency condition on the cutput of an MG Set or on the alternate supply would trip one or both of the EPAs. This protects the RPS components and auxiliaries from damage due to sustained abnormal voltage conditions (overvoltage, undervoltage or underfrequency).

The 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> maximum service limit of an " inservice power supply" with only one EPA operable provides reasonable assurance that a single failure would not prevent an abnormal voltage condition from being detected prior to damaging RPS components. The " inservice power supplies" are defined as either the two RPS MG Sets or one RPS MG Set and the alternate power source fed from B10/B6.

The 30 minute maximum service limit without either EPA operable provides reasonable assurance that an abnormal voltage condition would not damage RPS 1 components. The tripping of an RPS power supply to an RPS bus will result in a half-scram on that channel.

Revision Amendment No. 199

-,l; BASIS: '(Cont'd) 4.9 The diesel fuel oil quality must be checked to ensure proper operation of the diesel generators. Water content should be minimized because water in the fuel could contribute to excessive damage to the. diesel engine.

, When it is determined that some auxiliary electrical equipment is out of service, the increased surveillance required in Section 4.5.F is deemed adequate to provide assurance that the remaining equipment will be operable.

The Electrical Protection Assemblies (EPAs) on the RPS inservice power supplies (either two motor generator sets or one motor. generator and the alternate supply), consist of protective relays that trip their incorporated circuit breakers on overvoltage, undervoltage or underfrequency conditions.

There are 2 EPAs in series per power source. It is necessary to periodically test the relays to ensure the sensor is operating correctly and to ensure the trip unit is operable. Based on experience at conventional. and nuclear power f plants, a six month frequency for the channel functional test is established.

This frequency is consistent with the Standard Technical Specifications.

The EPAs of the power sources to the RPS shall be determined to be operable by performance of a channel calibration of the relays once per operating cycle.

During calibration, a transfer to the alternate power source is required; I however, prior to switching to alternate feed, de-energization of the i applicable MG set power source must be accomplished. This results in a half-scram on the channel being calibrated until the alternate power source is connected and the half scram is cleared. Based on operating experience, drift of the EPA protective relays is not significant. Therefore, to avoid possible spurious scrams, a calibration frequency of once per cycle is established.

l-l Revision Amendment No.

201

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