ML20041D369

From kanterella
Jump to navigation Jump to search
Forwards 82-003/03L-0.Detailed Event Analysis Encl
ML20041D369
Person / Time
Site: Oyster Creek
Issue date: 02/19/1982
From: Fiedler P
GENERAL PUBLIC UTILITIES CORP.
To: Haynes R
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20041D370 List:
References
NUDOCS 8203050266
Download: ML20041D369 (3)


Text

. .

GPU Nuclear p

  • U ear 100 Interpace Parkway Parsippany, New Jersey 07054 201 263-6500 TELEX 136-482 Writer's Direct Dial Number:

February 19J932

/^

/ + /.

Mr. Ronald C. Haynes, Administrator Region I j

- I~

,,,'z1 ,

U.S. Nuclear Regulatory Commission 631 Park Avenue

,f '

f Q *7 King of Prussia, PA 19406 k

\

'",p:

Dear Mr. Haynes:

ys <

.  ?,

x _

rsry,'

Subject:

Oyster Creek Nuclear Generating Station Ai:M Docket No. 50-219 Licensee Event Report Reportable Occurrence No. 50-219/82-03/3L This letter forwards three copies of a Licensee Event Report to report Reportable Occurrence No. 50-219/82-03/3L in compliance with paragraph 6.9.2.b.1 of the Technical Specifications.

Very truly yours, d

Pet'er C Fiedler

_Vice President & Director Cyster Creek PBF:lse Enclosures cc: Director (40 copies)

Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Director (3)

Office of Management Information and Program Control U.S. Nuclear Regulatory Commission Washington, D.C. 20555 NRC Resident inspector (1)

Oyster Cree' Nuclear Generating Station Forked River, NJ 08731 l

l 9203050266 820219 ar is a part of the General Public Utilities System PDR ADOCK 05000219 $g,7,L, S PDR ,

OYSTER CREEK NUCLEAR GENERATING STATION )

Forked River, New Jersey 08731 '

Licensee Event Report Reportable Occurrence No. 50-219/82-03/3L Report Date February 19, 1982 Occurrence Date January 22, 1982 Identification of Occurrence During surveillance testing, the Containment Spray Righ Drywell Pressure Indicating Switch IP-15B tripped at a value greater than the value given in the Technical Specifications, Table 3.1.1, Iten E.1.

This event is considered to be a reportable occurrence as defined in the Tech-nical Specifications, paragraph 6.9.2.b.1.

Conditions Prior to Occurrence The plant was in the cold shutdown condition.

Description of Occurrence 3

During performance of the " Containment Spray System Autanatic Actuation Test" (Surveillance Procedure 607.3.002) on January 22, 1982, the IP-15B trip point was found to exceed the Technical Specification desired setpoint. Testing of the four sensors yielded the following data:

Switch Designation Desired Setpoint As Found (psig) As Left (psig)

IP-15A <2.0 psig 1.97 1.88 IP-15B {2.0psig 2.11 1,76 IP-15C <2.0 psig 1.98 1.80 IP-15D 52.0psig 2.00 1.75 Apparent Cause of Occurrence The cause of the occurrence was instrument repeatability. Tne switch IP-15B was originally set at 1.97 psig and it tripped at 2.11 psig. The range for repeatability is 2-3% of full range, which in the case of the IP-15 switches is 0.2-0.3 psig. The difference of .14 psig for IP-15B between the setpoint and the actual trip point clearly falls within the ,

range if instrument repeatability.

4 Reportable Occurrence Page 2 Report No. 50-219/82-03/3L Analysis of Occurrence The Containment Spray Systs consists of two independent cooling loops, each of which is capable of reoving heat frun the primary containment in the event of a loss of coolant accident. The Containment Spray Systs will be initiated upon receipt of both a high drywell pressure signal and a reactor low-low water level signal.

Although switch IP-15B would have tripped at a slightly higher pressure than the desired setpoint, its actuation only would have been delayed by a fraction of a second. Also, the reactor low-low level setpoint is not reached until almost 4 seconds later after the setpoint for high drywell pressure is reached. Due to this and the fact that switch IP-15D for the same instrument channel would have actuated at the required setpoint, the safety significance of the event is considered minimal.

Corrective Action Pressure switch IP-15B was reset to trip within the Technical Specification limit of <2.0 psig (as shown in the "As Left" values in the Description of Occurrence). As can be seen frm the "As Left" values, starting frm this test, setpoint changes to allow for instrunent repeatability have been in-corporated into surveillance procedures. For the IP-15 switches, the setpointhasbeenchangedfrom2.0101 to 1.85 +.10 in order to reduce the frequency of exceeding the Technical

  • Specification limit. In addition, it is currently planned to replace these types of snap-action switches with an inproved model during the 1984 refueling outage.

Failure Data Manufactureu ITT,Barton Model: #288A Pressure Indication Switch Range: 0-10 psig

- - . _ _. , _ - ,