Part 21 Report - 1999-471
SCIENTECH
910 Cbpper Road
Gaithersburg, MD 2087~1399
Phone. 301-258-2410
Fax 301-258-2463
November 22, 1999
NRC Operations Center
Document Control Desk
1 Whiteflint North
11555 Rockville Pike
Rockville, MD 20852
DEVIATION UNDER 10CFR21
Dear Sir or Madam:
Enclosed please find Scientech, Inc.'s subsidiary NUS Instruments, Inc. (NUSI) formal report as a follow up to our previously provided October 28, 1999, preliminary notice. NUSI has opened a 10CFR21 file concerning this component and has numbered it as 21-99-01.
NUSI has opened a l0CFR21 file concerning this component and has numbered it as 21-99-01.
SCIENTECH/NUSI Contacts
Martin Booska
Scientech QA Representative
(301) 387-7012
Paul Loch
President
(407) 333-8895
If you have any questions or comments, please feel free to call.
President, SCIENTECH, Inc.
SCIENTECH Written Report
For Potential Deviation Under 1OCFIU1 - Reference File 21-994)
('ilitial Facsimile Report Submitted to the NRC on 10/28/1999)
REPORTING INDIVIDUAL
Paul Loch | Phone:407-333-8895 |
SCIENTECH Inc. - Presidents Office | Fax: 407-333-0735 |
2124 Silver Leaf Court | E-Mail:ploch@scientech.com |
Longwood, FL 32779-2757 | |
AFFECTED FACILITY AND PRODUCT WHICH IS NON-COMPLIANT
The facility is Carolina Power & Light, Robinson Plant. The Basic Component is a Low Level Amplifier used to process signals from resistance temperature detectors (RTDs). The module is NUS Instruments Model No. RTL85O
SUPPLYING HRM IDENTIFICATION
NUS Instruments, Inc., a wholly owned subsidiary of SCIENTECH, Inc.
440 W. Broadway
IdahoFalls, ID 83402
DESCRIPTION OF DEFECT AND ASSOCIATED SAFETY HAZRD (INCLUDES THE DATE THAT INFORMATION WAS OBTAINED)
NUS Instruments Model RTL85O Low Level Amplifiers were installed in the Robinson Plant at Carolina Power & Light as replacement modules for Hagan Model 118 modules and NUS Instruments Model RTD85O modules due to the RTh's better temperature coefficients. The modules were being used to monitor primary plant temperatures of the cold and hot legs to provide Tave and AT indications for operators. The lead length compensation circuitry on the RTL converter PC board has its polarity inverted. This results in the output of the RTL, when configured in three wire mode, to read higher than it actually should. The magnitude is dependent upon the range configured, the RTD type, the lead resistance and other factors. This error can result in actions being taken to control the reactor based upon incorrect information. NUS Instruments became aware of this problem on October 22, 1999 and a lOCFR2l log entry was made with the number 21-99-01 assigned to it.
THE NUMBER AND LOCATION OF AIL PRODUCTS AFFECTED
Twelve modules (PIN: NUS-AOO2PA-1, Rev. 0, configured for three wire RTD operation using RTh Personality Module (RPM) P/N: NUS-BOO3PA-3, Rev. 0) were supplied to CP&L Robinson Plant in February of 1998 and an additional module (P/N: NUS-AOO2PA-113, Rev. 1, configured for three wire RTD operation using RPM PIN: NUS-BOO3PA-3, Rev. 1) was supplied to the same facility in May of 1999.
CORRECTIVE ACTION THAT AS BEEN OR IS BEING TAKEN
Corrective action for the basic component is to replace the internal RTL Personality Module (RPM, PIN: NUS-BOO3PA-3) in all RTL modules wtth a new RPM built to a revised schematic to correct for the inverted polarity on the PC board. Corrective action to include:
| 1) | Breadboard and validate RPM changes to correct polarity (completed) |
| 2) | Revise board schematic and assembly drawings to reflect changes (completed) |
| 3) | Revise all accompanying documentation to address changes (completed) |
| | a) | TestPlan |
b) | Test Procedure |
c) | Operating and Maintenance Manual |
d) | Qualification Report (800 and 500 Series) |
e) | EDB (NUS-BOO3EA) |
| 4) | Assign Project Manager for Return Authorization 99-020 (completed) |
5) | Build new revision 3 RPM and verity acceptability via Testing (completed) |
6) | Build new revision 3 production RPMs to replace all earlier versions (completed November 23, 1999 to be ready for delivery no later than January 14, 2000) |
7) | Make arrangements with affected utility to replace old RPMs with new ones (completed) |
8) | Make positive accounting by serial number of all revision 0, 1 and 2 RPMs (completed) |
NUS Instruments has verified through testing that the units equipped with revision 3 RPMs properly compensate for lead length resistance and is confident no recurrence of this problem will occur. All affected utilities have been notified of this problem and all affected components have been recalled (including modules in Non-Safety Related applications).
RESPONSIBLE PARTY FOR CORRECTIVE ACTION
NUS Instruments
ESTIMATE OF WHEN CORRECTIVE ACTION WILL BE COMPLETE
14 January 2000
CAUSES FOR 'THE DEVIATION
1. | Procedures were not in place to require that changes made during prototyping were verified/tested, properly documented, and carried through to the production design. |
2. | Production Test Procedure did not require testing to verity proper compensation for lead length resistance. |
CORRECTIVE ACTION TO PREVENT RECURRENCE
1. | Create a Standard Operating Procedure (SOP) to cover prototyping and define the process where the design inputs are officially extracted from the myriad of sources to a single design specffication at the start of tlie project. This needs significant review prior to completion of any milestones in the Project Engineering Management QA. |
2. | Revise existing production test procedures to include verification of proper compensation for lead length resistance for three wire RTD's. |
3. | Provide training on new SOP to all personnel who will use it in the performance of their job duties. |
NOTE: | Estimated date for completion of corrective action to prevent recurrence is 15 March 2000 |
COMMENTS OR ADVISE TO PURCHASE RSI LICENSEES
NUS Instruments recommends that all facilities ensure that inherent lead resistance compensation capability of any three wire RID converter performs properly. For more technical information, contact: Niel Skousen, Sr. Engineer, Phone: (208) 525-37421(208) 52~9229, Fax: (208) 529-4721, Email - nskousen@scientech.com
SCIENTECH NUSI CONTACTS
Paul Loch | Martin Booska |
President | SCIENTECH QA Manager |
(407) 333-8895 | (301) 387-7012 |
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