ENS 45548

v t e ENS Event
05:00 Dec 8, 2009
Title	Woodward Governor Servo Failure Due to Silver Sulfide Corrosion of Surface Mount Resistors
Event Description	Woodward failure analysis report #85572-R001, dated 10/9/09, addressed two separate [model] PGPL remote servo failures. The failure analysis report discusses a silver sulfide corrosion issue with surface mount resistors used in the PGPL remote servo feedback transmitter circuitry. Woodward part number 9903-539 consists of a PGPL actuator and a remote servo. The PGPL actuator is mounted on the turbine's governor drive and the remote servo (Woodward part number 5296-044) is mounted at the steam valve. Hydraulic lines interconnect the PGPL to the remote servo. The PGPL actuator and remote servo was supplied by Engine Systems, Inc. (ESI) to the Callaway and Vogtle nuclear plants as part of a digital governor upgrade (Woodward 505 control) on their steam turbine generators. These are the only nuclear plants that use the P/N 9903-539 actuator remote servo assembly. LISTING OF WOODWARD PIN 9903-539 PGPL ACTUATORS WITH SUSPECT RESISTORS Serial Number Born Date Shipped to 12369963 Nov 2000 Callaway 13305595 July 2002 Callaway 13798414 May 2004 Vogtle 13798415 May 2004 Callaway 14141720 Feb 2005 Vogtle 14409400 Sep 2005 Vogtle Note: Serial numbers 12369963 and 13798414 recently had the feedback board replaced during the failure analysis; these require no further corrective action.

ENS 45548 +/-
Where
Engine Systems, Inc. Rocky Mount, North Carolina (NRC Region 1)
Organization:	Engine Systems, Inc.
Reporting

10 CFR 21.21
Time - Person (Reporting Time:+6.37 h0.265 days <br />0.0379 weeks <br />0.00873 months <br />)
Opened:	Paul Stepantschenko 11:22 Dec 8, 2009
NRC Officer:	Dan Livermore
Last Updated:	Dec 8, 2009
45548 - NRC Website
v • d • e

v t e Emergency Notification System
Engine Systems, Inc. with 10 CFR 21.21
WEEKMONTHYEAR2009-12-08T05:00:00 [Table view]
[ENS list for Engine Systems, Inc.]

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