United States Nuclear Regulatory Commission - Protecting People and the Environment

ACCESSION #:  9607030156 

ITT BARTON
INDUSTRY ADVISORY
(May 15, 1996)

      MODEL 765/765A TRANSMITTER ZERO & SPAN POTENTIOMETER CONCERNS

ITT Barton supplies Model 765/765A Differential Pressure Electronic
Transmitters to the commercial nuclear power industry with harsh
environment (LOCA) IEEE-323/344 qualifications.  ITT Barton has just
recently confirmed that certain lots of the commercial grade
potentiometers used in these transmitters have been supplied with
lubrication in noncompliance with the engineering/purchasing
specification requirements.

This Industry Advisory is applicable only to Model 765 and 765A
Electronic Transmitters qualified under ITT Barton Engineering Report R3-
765-2, where the accident ambient conditions include pressure exposures
in excessive of 10 psig and significant moisture is present.  For those
installations where the accident environment is relatively benign
(outside containment applications) the findings of this Advisory may not
apply.  Because ITT Barton sales records indicate that many Model
765/765A Transmitters have been purchased for outside containment
installations, and it may be possible that some of the installations need
not remain functional after the start of the accident, we have left the
final determination for 10CFR21 applicability to the notified purchasers
of the instruments of concern, consistent with Section 21.21 (b) of 
10CFR21.  A courtesy copy of this Advisory and a list of the notified
customers have been supplied to the NRC consistent with the Defect and
Noncompliance Reporting intent of 10CFR21.

Upon request, ITT Barton will supply a set of new potentiometers (zero
and span) along with a potentiometer replacement procedure to any
customer who determines that replacement of these parts is prudent in
their Model 765/765A Transmitters.  All new Model 765/765A Transmitters
shipped from the ITT Barton factory after the date of this Advisory
utilize parts which satisfy the engineering specifications.

Qualification testing has shown that the same lubricated potentiometers
are not a concern for LOCA harsh environment installations where the
ambient atmosphere does not enter the transmitter electronics case.  In
the Model 765/765A Transmitter, the electronics case is a deep drawn thin
wall stainless steel canister whose back is subject to deflection under
elevated ambient pressure conditions (>10 psig) allowing the ambient
atmosphere to enter the transmitter electronics case at the torque tube
penetration seal.  The moisture and chemical environment of the
containment LOCA conditions causes a breakdown in the potentiometer
lubrication resulting in corrosion of the potentiometer contacts.

Questions regarding this issue should be addressed to J. Anderson,
Director of ITT Barton Quality Assurance at (818) 961-2547.


Bechtel Overseas Corporation 
P.O.  Box 34178
Phoenix, AZ 85067-4178

ATTN: Q. A.  Manager

Bell Power Corporation
1340 Lexington Ave.
Rochester, NY 14606

ATTN: Q. A.  Manager

American Air Filter
20th Floor - Q. A.  
1 Riverside Plaza 
Columbus, OH 43215

ATTN: Mr.  J.  B.  Brittan

Illinois Power
P.O.  Box 678
Clinton, IL 61727

ATTN; M. R. Hiter

Consumer Power
1945 W.  Parnall
Jackson, MI 49201

ATTN: J.E.  Harding

Entergy Operations, Inc.
Route 3, Box 137G 
Russellville, AR 72801

ATTN: Charles R.  Gaines
      Supr., Industry Events Analysis

Nebraska Public Power
P.O.  Box 98
Brownville, NE 68321

ATTN: Guy Horn

Prematecnica, S.A.
C/Ulises, 18
Madrid - 28043 Spain

ATTN: Q.A.  Manager


Tennessee Valley Authority
1101 Market Street, BR 4J
Chattanooga, TN 37402-2801


ATTN: R.R.  Baron

Westinghouse Electric Corporation
Nuclear Services Division
P. O.  Box 655
Pittsburgh, PA 15230-0855

ATTN: Q.A.  Manager

United Engineers & Constructors
P. O.  Box 221
Hancocks Bridge, NY 03038
ATTN:  Q. A.  Manager

Yankee Atomic Electric Company 
580 Main St.
Bolton, MA 01740-1398

ATTN: Sandra Nichols


Georgia Power Co.
Plant E.I.  Hatch
P. O. Box 439
Baxley, GA 31513

ATTN: Q. A.  Manager

ITT Barton Industrial Sales 
349 W. 195th Street
Glenwood, IL 60425

ATTN: Q. A.  Manager


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