ML23192A062

Engine Systems, Inc., 10CFR21 Reporting of Defects and Non-Compliance, Report No. 10CFR21-0136, Rev. 0

ML23192A062
Person / Time
Site:	Nine Mile Point
Issue date:	06/30/2023
From:	Woolard S Engine Systems
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML23192A062 (1)

Text

ENGINE SYSTEMS, INC.

175 Freight Road Telephone: 252/977-2720 Rocky Mount. NC 27804 Fax: 252/446-1134 June 30, 2023 U.S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555-0001

Subject:

10CFR21 Reporting of Defects and Non-Compliance -

Engine Systems, Inc. Report No. 10CFR21-0136, Rev. 0 Voltage Regulator Chassis - Incorrect Bus Bar Installation P/Ns: 72-12300-100-ESI 72-14200-100-ESI 72-14000-100-6020

Dear Sir / Madam:

The enclosed report addresses a reportable notification for voltage regulator chassis, P/N's: 72-12300-100-ESI , 72-14200-100-ESI , and 72-14000-100-6020.

A copy of the report has also been mailed to our affected nuclear customers.

Please sign below, acknowledging receipt of this report, and return a copy to the attention of Document Control at the address above (or, fax to number 252/446-3830) within 10 working days after receipt.

Yours very truly, ENGINE SYSTEMS, INC.

Susan Woolard Document Control Coordinator Please let us know if ANY of your mailing information changes - name of recipient, name of company/facility, address, etc. Mark the changes on this acknowledgment form and send to us by mail or FAX to the number above.

RECEIVED: _ _ _ _ _ _ __

71 DATE:

Quality Performance With Pride

ENGINE SYSTEMS, INC.

175 Freight Road , Rocky Mount, NC 27804 Telephone: 252/977-2720 Fax: 252/446-1134 Report No. 10CFR21-0136 Rev. O: 06/30/23 10CFR21 REPORTING OF DEFECTS AND NON-COMPLIANCE COMPONENT: Voltage Regulator Chassis - Incorrect Bus Bar Installation P/Ns: 72-12300-100-ESI 72-14200-100-ESI 72-14000-100-6020 SYSTEM : Emergency Diesel Generator CONCLUSION: Reportable in Accordance With 10CFR21 Prepared By:

~;b Engineering Manager Date. ~/3o/t3 Reviewed By: ~ (U)-- Date: 6Lib /21 Quality Assurance Manager Quality Performance With Pride

Report No. 10CFR21-0136 Record of Revisions Page: 1 of 1 REV DATE PAGE DESCRIPTION 0 06/30/23 Initial issue.

Report No. 10CFR21-0136 Revision: 0 Date: 06/30/23 Page: 1 of 4 Pursuant to 10 CFR 21.21(d)(4), ESI is presenting the required information as follows:

(i) Name and address of the individual or individuals informing the Commission.

John Kriesel Dan Roberts Engineering Manager Quality Manager Engine Systems Inc. Engine Systems Inc.

175 Freight Rd. 175 Freight Rd.

Rocky Mount, NC 27804 Rocky Mount, NC 27804 (ii) Identification of the basic component supplied within the United States which fails to comply or contains a defect.

Voltage regulator chassis with the following part numbers:

• 72-12300-100-ESI

• 72-14200-100-ESI

• 72-14000-100-6020 (iii) Identification of the firm supplying the basic component which fails to comply or contains a defect.

Engine Systems Inc. (ES/)

(iv) Nature of the defect or failure to comply and the safety hazard which is created or could be created by such defect of failure to comply .

Copper bus bars are used at rectifier diode pigtail connections CR1, CR2, CR3, CR4, and CR7 to provide a common connection point for associated wiring to minimize the number of conductors on a single fastener. It is intended for the conductors to clamp directly to the bus bar, thereby maintaining a low resistance conduction path between components. ES/ has determined the bus bars were installed incorrectly whereby the conductors are not clamped in direct contact, resulting in current flow through the stainless steel fasteners. This configuration is undesired and will result in unnecessary heat generation which may lead to failure of the connection and therefore failure of the automatic voltage regulator (A VR) assembly. The A VR is relied upon to automatically regulate emergency diesel generator (EOG) terminal voltage. Failure of the AVR would impact ability of the EOG to perform its safety-related function and therefore may impact the nuclear plant's ability to manage safety-related loads during an emergency event.

(v) The date on which the information of such defect or failure to comply was obtained.

May 17, 2023 (vi) In the case of a basic component which contains a defect or fails to comply, the number and location of these components in use at, supplied for, being supplied for, or may be supplied for, manufactured, or being manufactured for one or more facilities or activities subject to the regulations in this part.

The extent of condition is limited to the following voltage regulator assemblies:

Customer PO ESI Sales Qty Part Number Customer C of C Date Number Order Shipped 72-12300-100-ESI Constellation Energy - Nine Mile Point 00702105 8003195 2 March 1, 2021 72-14200-100-ESI Avaltec I CFE - Laguna Verde (Div Ill) 1879-20 I 700507054 8003429 2 May 16, 2021 72-14000-100-6020 Avaltec I CFE - Laguna Verde (Div 11) 1966 / 700519535 8003506 2 October 25, 2022 Table 1: Voltage Regulator Assemblies Affected

Report No. 10CFR21-0136 Revision: 0 Date: 06/30/23 Page: 2 of4 (vii) The corrective action which has been, is being, or will be taken; the name of the individual or organization responsible for the action; and the length of time that has been or will be taken to complete the action.

For affected users:

• Voltage regulators installed:

Bus bar installation should be corrected immediately by restacking the components to ensure direct contact with all conductors. See section viii below for details.

• Voltage regulators in inventory (not installed):

The bus bar installation should be corrected prior to installation. If desired, the customer may perform on site or the voltage regulator chassis may be returned to ES/ for rework.

For ES/:

The shop traveler used for the build-up of voltage regulator chassis will be enhanced to provide additional guidance and a verification will be added to ensure proper installation of the bus bar. This is in process and will be incorporated for future builds prior to shipment.

(viii) Any advice related to the potential defect or failure to comply about the facility, activity, or basic component that has been, is being, or will be given to purchasers or licensees.

Photos below show an example of an incorrectly installed bus bar (photo 1) and one that is correctly installed that ensures proper conduction (photo 2). Photos and figures on the following pages provide additional information.

Ring lug terminals are not in direct contact with copper bus bar and rely on conduction through the fasteners.

g terminals are in direct with copper bus bar, no on conduction through rs.

Report No. 10CFR21-0136 Revision: 0 Date: 06/30/23 Page: 3 of4 WIR E DIOD E LUG \ / PIGTAIL

\  !

\ I COPP ER

\ \

I I

BUS BAR

\ i

1/4 - 20 BOLT

---

if FLAT WASHER FLAT WASHER l NUT J

/ tj \ FLAT WAS HER

"/ 4" GLAS TIC LOCK WASHER FLAT WASHER J Figure 1: Cross Section - Incorrect Bus Bar Install (Note bus bar is not in direct contact with wire lug and diode pigtail)

WIRE DIODE LUG-\ PIGTAIL COPPER

\ \

BUS BAR l * /4 - 20 BOLT i .......,ef LOCK ~ FLAT WASHER FLAT WASHER ____/ j I 1/4" GLASTIC LOCKWASHER . I FLAT WASH ER_J Figure 2: Cross Section - Correct Bus Bar Install (Note wire lug, diode pigtail, and bus bar stacked in direct contact)

Report No. 10CFR2 1-0136 Revision: 0 Date: 06/30/23 Page: 4 of4 Figure 3 and photo 3 below show location of the bus bars on the voltage regulator chassis.

0 0

Location of the five bus bars at rectifier diodes CR1 , CR2, CR3, CR4, & CR7 Figure 3: Outline Drawing - Chassis Upper Half