United States Nuclear Regulatory Commission - Protecting People and the Environment

Morning Report for June 27, 2006

Headquarters Daily Report

To top of page


Part 21 2006-0013-00 - Prime Measurement Products (formerly ITT Barton) Models 763 and 763A Gage Pressure Transmitters and Model 764 Differential Pressure Transmitters


FULTON, Missouri
Dockets: 05000483

License No:

MR Number: H-2006-0013
Date: 06/21/2006



On June 21, 2006 the NRC was provided initial 10 CFR Part 21.21 notification of the subject defect and its evaluation.

The Callaway Plant received a notification dated May 18, 2006, from PRIME Measurement Products (formerly ITT Barton) stating Barton Model 763 and 763A Gage Pressure Transmitters and Model 764 Differential Pressure Transmitters may have defective external lead-wire connectors, which could affect their performance during an accident. The notification provided by PRIME stated the affected transmitters were manufactured after May 1982 and shipped from the factory prior to April 1, 2006.

The potential defect is characterized as follows: The transmitters' external lead wires enter the electronics enclosure through a hermetic seal called a connector assembly. The external lead wires are soldered to the glass sealed pins of the hermetic seal. Epoxy potting is used to structurally support the soldered wire connections and establish a seal to protect the solder connections from shorting, which could be caused by an electrically conductive accident environment. The defect is that the insulated portions of the wires in the connectors, manufactured after May 1982, may not be embedded deeply enough into the epoxy potting to provide an electrical connection that would not be affected in an accident environment.

The notification also states that actual transmitter installation may preclude shorting of exposed conductors due to the existence of conduit, conduit seals, and special wire connectors which could protect the exposed wires at a defective connector from conductive moisture.

Callaway identified thirty applicable Barton transmitters and connector assemblies in warehouse stock. Inspections of these operational spare parts identified three connectors, which had exposed conductors external to their seal. One connector had this defect on one lead wire and two connectors had this defect on both lead wires.

Callaway has also identified that thirty-nine potentially affected transmitters are installed in the plant. An inspection plan was developed to perform the required inspections, based on safety significance, ALARA considerations, and potential accident environmental conditions. Additional reporting requirements associated with the installed components will be evaluated by the licensee under 10 CFR Part 50.72 as required.

On June 19, 2006, Callaway Plant personnel completed evaluations and determined the defective connections constitute a defect per 10 CFR Part 21.

The NRC has contacted the vendor (PRIME Measurement Products) and determined they have sent letters (with receipt notification requested) to all their customers who have purchased nuclear safety-related parts from them in the past including: all Westinghouse Pressurized Water Reactor plants (PWRs), General Electric Nuclear Energy, 13 Boiling Water Reactor (BWR) plants, as well as, additional third party supply vendors and international customers.


Name Office Abbrev Phone No E-Mail
KING, MARK S NRR (301) 415-1150 MSK1@nrc.gov
Page Last Reviewed/Updated Thursday, March 29, 2012