ML060950235

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GALL AMP: XI.E2, Electrical Cables and Connections Not Subject to 10 CFR 50.49 Environmental Qualification Requirements Used in Instrumentation Circuits (Audit Worksheet GALL Report AMP)
ML060950235
Person / Time
Site: Vermont Yankee File:NorthStar Vermont Yankee icon.png
Issue date: 03/22/2006
From: Morgan M
NRC/NRR/ADRO/DLR/RLRC
To:
Office of Nuclear Reactor Regulation
morgan M NRR/NRC/DLR/RLRC, 415-2232
Shared Package
ML060950189 List: ... further results
References
%dam200611, TAC MC9668
Download: ML060950235 (7)


Text

XI.E2 Electrical Cables and Connections Not Subject to 10 CFR 50.49 EQ Requirements Used in Instrumentation Circuits 1

AUDIT WORKSHEET GALL REPORT AMP PLANT: ______________________________

LRA AMP: __________________________

REVIEWER: ______________________

GALL AMP: XI.E2, Electrical Cables and Connections Not Subject to 10 CFR 50.49 Environmental Qualification Requirements Used in Instrumentation Circuits DATE: __________________________

Program Element Auditable GALL Criteria Documentation of Audit Finding Program Description A. In most areas within a nuclear power plant, the actual ambient environments (e.g., temperature, radiation, or moisture) are less severe than the plant design environment. However, in a limited number of localized areas, the actual environments may be more severe than the design environment. Conductor insulation materials used in electrical cables may degrade more rapidly in adverse localized environments. An adverse localized environment is significantly more severe than the specialized service environment for the cable. An adverse variation in environment is significant if it could appreciably increase the rate of aging of a component or have an immediate adverse effect on operability. Exposure of electrical cables to adverse localized environments caused by heat, radiation, or moisture can result in reduced insulation resistance (IR). Reduced IR causes an increase in leakage currents between conductors and from individual conductors to ground. A reduction in IR is a concern for circuits with sensitive, high voltage, low-level signals such as radiation monitoring and nuclear instrumentation circuits because a reduced IR may contribute to signal inaccuracies.

Consistent with GALL AMP:

Yes No Document(s) used to confirm Criteria:

Comment:

B. The purpose of the aging management program described herein is to provide reasonable assurance that the intended Consistent with GALL AMP:

Yes No Document(s) used to confirm Criteria:

XI.E2 Electrical Cables and Connections Not Subject to 10 CFR 50.49 EQ Requirements Used in Instrumentation Circuits 2

Program Element Auditable GALL Criteria Documentation of Audit Finding functions of electrical cables that are not subject to the environmental qualification requirements of 10 CFR 50.49 and are used in instrumentation circuits with sensitive, high voltage, low-level signals exposed to adverse localized environments caused by heat, radiation or moisture will be maintained consistent with the current licensing basis through the period of extended operation. This program considers the technical information and guidance provided in NUREG/CR-5643, IEEE Std. P1205, SAND96-0344, and EPRI TR-109619. In this aging management program, either of two methods can be used to identify the existence of aging degradation. In the first method, calibration results or findings of surveillance testing programs are evaluated to identify the existence of cable aging degradation. In the second method, direct testing of the cable system is performed.

Comment C. This program applies to high-range-radiation and neutron flux monitoring instrumentation cables in addition to other cables used in high voltage, low-level signal applications that are sensitive to reduction in IR. For these cables, GALL XI.E1 does not apply. As stated in NUREG/CR-5643, "The major concern with cables is the performance of aged cable when it is exposed to accident conditions." The statement of considerations for the final license renewal rule (60 Fed. Reg. 22477) states, "The major concern is that failures of deteriorated cable systems (cables, connections, and penetrations) might be induced during accident conditions." Since they are not subject to the environmental qualification requirements of 10 CFR 50.49, the electrical cables covered by this aging management program are either not exposed to harsh accident conditions or are not required to remain functional during or following an accident to which they are exposed.

Consistent with GALL AMP:

Yes No Document(s) used to confirm Criteria:

Comment

1. Scope of Program A. This program applies to electrical cables and connections (cable system) used in circuits with sensitive, high voltage, low-level signals such as radiation monitoring and nuclear Consistent with GALL AMP:

Yes No Document(s) used to confirm Criteria:

XI.E2 Electrical Cables and Connections Not Subject to 10 CFR 50.49 EQ Requirements Used in Instrumentation Circuits 3

Program Element Auditable GALL Criteria Documentation of Audit Finding instrumentation that are subject to aging management review.

Comment

2. Preventive Actions A. No actions are taken as part of this program to prevent or mitigate aging degradation.

Consistent with GALL AMP:

Yes No Document(s) used to confirm Criteria:

Comment:

3. Parameters Monitored/

Inspected A. The parameters monitored are determined from the specific calibration, surveillances or testing performed and are based on the specific instrumentation circuit under surveillance or being calibrated, as documented in plant procedures.

Consistent with GALL AMP:

Yes No Document(s) used to confirm Criteria:

Comment:

4. Detection of Aging Effects A. Review of calibration results or findings of surveillance programs can provide an indication of the existence of aging effects based on acceptance criteria related to instrumentation circuit performance. By reviewing the results obtained during normal calibration or surveillances, an applicant may detect severe aging degradation prior to the loss of the cable and connection intended function. The first reviews will be completed before the period of extended operation and at least every ten years thereafter. All calibration or surveillance results that fail to meet acceptance criteria will be reviewed for aging effects when the results are available.

Consistent with GALL AMP:

Yes No Document(s) used to confirm Criteria:

Comment:

B. In cases where a calibration or surveillance program does not include the cabling system in the testing circuit, or as an alternative to the review of calibration results described above, the applicant will perform cable system testing. A proven cable system test for detecting deterioration of the insulation system (such as insulation resistance tests, time domain reflectometry tests, or other testing judged to be effective in determining cable Consistent with GALL AMP:

Yes No Document(s) used to confirm Criteria:

Comment:

XI.E2 Electrical Cables and Connections Not Subject to 10 CFR 50.49 EQ Requirements Used in Instrumentation Circuits 4

Program Element Auditable GALL Criteria Documentation of Audit Finding insulation condition as justified in the application) will be performed. The test frequency of these cables shall be determined by the applicant based on engineering evaluation, but the test frequency shall be at least once every ten years.

The first test shall be completed before the period of extended operation.

5. Monitoring and Trending A. Trending actions are not included as part of this program because the ability to trend test results is dependent on the specific type of test chosen. However, test results that are trendable provide additional information on the rate of degradation.

Consistent with GALL AMP:

Yes No Document(s) used to confirm Criteria:

Comment:

6. Acceptance Criteria A. Calibration results or findings of surveillance and cable system testing results are to be within the acceptance criteria, as set out in procedures.

Consistent with GALL AMP:

Yes No Document(s) used to confirm Criteria:

Comment:

7. Corrective Actions A. Corrective actions such as recalibration and circuit trouble-shooting are implemented when calibration or surveillance results or findings of surveillances do not meet the acceptance criteria. An engineering evaluation is performed when the test acceptance criteria are not met in order to ensure that the intended functions of the electrical cable system can be maintained consistent with the current licensing basis. Such an evaluation is to consider the significance of the test results, the operability of the component, the reportability of the event, the extent of the concern, the potential root causes for not meeting the test acceptance criteria, the corrective actions required, and likelihood of recurrence. As discussed in the appendix to this report, the staff finds the requirements of 10 CFR Part 50, Appendix B, acceptable to address the corrective actions.

Consistent with GALL AMP:

Yes No Document(s) used to confirm Criteria:

Comment:

8.

A. As discussed in the appendix to this report, the staff finds the Consistent with GALL AMP:

Yes No

XI.E2 Electrical Cables and Connections Not Subject to 10 CFR 50.49 EQ Requirements Used in Instrumentation Circuits 5

Program Element Auditable GALL Criteria Documentation of Audit Finding Confirmation Process requirements of 10 CFR Part 50, Appendix B, acceptable to address confirmation process.

Document(s) used to confirm Criteria:

Comment:

9.

Administrative Controls A. As discussed in the appendix to this report, the staff finds the requirements of 10 CFR Part 50, Appendix B, acceptable to address the administrative controls.

Consistent with GALL AMP:

Yes No Document(s) used to confirm Criteria:

Comment:

10. Operating Experience A. Operating experience has identified a case where a change in temperature across a high range radiation monitor cable in containment resulted in substantial change in the reading of the monitor. Changes in instrument calibration can be caused by degradation of the circuit cable and are a possible indication of electrical cable degradation. The vast majority of site specific and industry wide operating experience regarding neutron flux instrumentation circuits is related to cable/connector issues inside of containment near the reactor vessel Consistent with GALL AMP:

Yes No Document(s) used to confirm Criteria:

Comment:

XI.E2 Electrical Cables and Connections Not Subject to 10 CFR 50.49 EQ Requirements Used in Instrumentation Circuits 6

EXCEPTIONS Item Number Program Elements LRA Exception Description Basis for Accepting Exception Documents Reviewed (Identifier, Para.# and/or Page #)

1.
2.

ENHANCEMENTS Item Number Program Elements LRA Enhancement Description Basis for Accepting Enhancement Documents Reviewed (Identifier, Para.# and/or Page #)

1.
2.

DOCUMENT REVIEWED DURING AUDIT Document Number Identifier (number)

Title Revision and/or Date

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