ML19276H355

Notifies That Reactor Bldg Spray Pump Motors Do Not Meet Design Criteria.Motors Not Able to Reach Normal Operating Speed within Six Seconds Under Worst Undervoltage Condition. No Corrective Action Will Be Taken

ML19276H355
Person / Time
Site:	Three Mile Island
Issue date:	02/04/1974
From:	John Miller METROPOLITAN EDISON CO.
To:
Shared Package
ML19276H353	List: ML19276H355
References
NUDOCS 7910160692
Download: ML19276H355 (2)

Text

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AETROPOLITAN EDISON COMPANY ... =.ciabr arcensuvuucuriuriescaucuricn j OFFICE BOX 542 *REACl$G, PENNSYLVANI A 19CO3 TELEFiiONE 215 - 929-3601 February h, 197h Dr. D. R. Knuth, Director Directorate of Regulatory Operations United States Atocic Energy Cc==ission Washington, D. C. 20545

Subject:

Three Mile Island Units 1 and 2 Docket Nos. 50-289 and 50-320 Reactor Building Spray Pu=p Motors

Dear Dr. Knuth:

You were notified on January 3, 1974, of a situation which =ay be considered reportable under 10CFR50.55(e), " Conditions of Construction".

This situation related to Reactor Building Spray Pump Motors.

DESCRIiT?n" U.P INCIDENT The manufacturer of the Three Mile Island Unit 1 Reactor Building Spray Pump Motors advises that the starting tine of these notors does not meet the requirecents of the purchase order specification.

The motor: are 250 horsepower, 4000 volt, 60 H , 3600 RPM squirrel 2

cage water cooled cotors manufactured by Westinghouse's 3uffalo plant.

These motors are identified by Westinghouse shop order No. 68F20805.

The purchase order specification required these cotors to " accelerate their driven load to nor=al operating speed within six seconds at the worst voltage condition (i.e., 80% of rated voltage at the motor terminals)."

Westinghcuse advises that the ti=e required to accelerate load is as shown below:

Voltage, % Acceleration Time, Sec. 100 3.9 90 6.0 85 7.8 80 11.4 1413 359 7

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AFETYIMPI)TIONS been perfor=ed by Gilbert ,AssociatesAn Inc.

analysis of t Fe Engin esel Generator loading has Motors are loaded as part of Block 4 ofThe th Reactor Euilding Spray Pump to the diesel generator, sequence as indicated e engineered on Table safeguards loading 8-1 of the 83% (3453 volts) of the normal bus voltagthe initial ecreases bus voltage to comen mately 86% of the cotor rated voltages of 4000 Ve .

This(4160 volts) .

is approxi-the high speed diesel generator excitBased voltage in 1.12 seconds.

e on the data subm er will return the bus to full ratedgenerator diesel generator is below 100% voltageThe total time for =

voltage, plus the time a total of 5.02 seconds.

This 5.02 of the purchase order specification second acceleration ti=e meets, is 1 within six seconds. , i.e.,

full loaded motor accelerationthe inte condition for starting the subject spray e represents otors.

the pu=p worst case mThe die CJfJ.ECTIVE ACTICN PRCPOSED OR TA'3N Unit 1 Spray Puup and cotor performance will bNo corrective action is Engineered Safeguards Activation e deconstrated Test (TP600/21) during the Integrat Unit 2 Pumps are identical in type to the ThrThe motors for the Three M characteristic is more severe, howeveree Mile Island Unit 1 cotors.eactor Building Sp Three Mile Island Unit 2. The load times that motors. are longer thanThis more those report e

se,d fvere loading results e eration in acc ldue testin6 at voltages down toe voltage. 80% of rned rat dThese motors to Westinghouse for have co of the solution measured to the Three acceleration Mile times a a areIsland av il bl oUnit A decision 2 the on or problem= tmethod will be made after e.

Very truly yours, '

,A aff

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brh lJ.G. 0YMiller c:Mr. J. P. O'Reilly Vice President Mr. W. A. Verrochi 1413 360 9"

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