JAFP-11-0089, CFR 21 Report Concerning Defective Rosemount Model 710DU Master Trip Units

CFR 21 Report Concerning Defective Rosemount Model 710DU Master Trip Units

ML111960007
Person / Time
Site:	FitzPatrick
Issue date:	07/14/2011
From:	Bronson K Entergy Nuclear Northeast, Entergy Nuclear Operations
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
JAFP-11-0089
Download: ML111960007 (2)

Text

~Entergy Entergy Nuclear Northeast Entergy Nuclear Operations, Inc.

James A. FitzPatrick NPP P.O. Box 110 Lycoming, NY 13093 Tel 315-349-6024 Fax 315-349-6480 Kevin Bronson Site Vice President - JAF JAFP-11-0089 July 14, 2011 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001

SUBJECT:

10 CFR 21 Report Concerning Defective Rosemount Model 71 ODU Master Trip Units James A. FitzPatrick Nuclear Power Plant Docket No. 50-333 License No. DPR-59

REFERENCE:

Emerson Process Management, Rosemount Nuclear Instruments Failure Analysis Report FA1000064750

Dear Sir or Madam:

Pursuant to 10 CFR 21.21 (d)(3)(ii) Entergy Nuclear Operation's (END) James A. FitzPatrick Nuclear Power Plant (JAF) is providing this notification of a defect in Rosemount Model 71 ODUOTR34033 trip units supplied as basic components.

Rosemount Nuclear Instruments, Inc. supplied four (4) model 710DUOTR34033 trip units (Serial numbers 0536402,0536358,0536359, and 0536360) as basic components. The trip units as supplied failed pre-installation testing; the trip units would not energize.

The four trip units were returned to Rosemount for failure analysis [Reference]. It was determined that the R1 resistor on the trip unit had failed. The R1 resistor acts as a shunt across transistor 01 during the start-up of the trip unit. With the failed R1 resistor the trip unit could not power up.

The vendor's analysis of the resistor failure, determined that the resistor failed due to corrosion of the nichrome wire used in the resistor, potentially caused by contaminates in the flux used during the manufacture of the resistor.

JAF evaluated the failures and on June 14, 2011, determined that the defect represented a substantial safety hazard due to the fact that certain applications at JAF require that the trip unit power up to perform its function. Since the defective trip units would not have been capable of powering up, if installed in their defective condition the units could have prevented a safety

JAFP-11-0089 Page 2 of 2 function from being accomplished. The preliminary results of this determination were reported to the NRC via fax as required by 10 CFR 21.21 (d)(3)(i), on June 16, 2011.

There were a total of four (4) defective units supplied to JAF, all of which were returned to Rosemount for failure analysis. None of the defective units were installed in the plant.

The defect identified on the subject trip units was documented in the corrective action program.

The corrective actions were to test the remaining trip units in stock to determine if there were additional defective trip units; to return any defective trip units to Rosemount for analysis and repair; to evaluate Rosemount anomaly report; and determine if a 10 CFR 21 Report was required. These actions were completed within ninety-one days of the initial identification of a potential deficiency. There are no remaining corrective actions.

Because the defect is readily identifiable during testing no additional recommendations are being made with this notification.

There are no regulatory commitments made in this letter.

Should you have any further questions regarding this matter please contact Mr. Eugene Dorman, Acting Licensing Manager, at (315) 349-6810.

S;Z:J21-1 Kevin Bronson Site Vice President KB/ed cc: Regional Administrator Resident Inspector NRR Project Manager Document Components: 000 JAFP-11-0089