Information Notice 1993-23, Weschler Instruments Model 252 Switchboard Meters

Weschler Instruments Model 252 Switchboard Meters
	ML031080024
Person / Time
Site:	Beaver Valley, Millstone, Hatch, Monticello, Calvert Cliffs, Dresden, Davis Besse, Peach Bottom, Browns Ferry, Salem, Oconee, Mcguire, Nine Mile Point, Palisades, Palo Verde, Perry, Indian Point, Fermi, Kewaunee, Catawba, Harris, Wolf Creek, Saint Lucie, Point Beach, Oyster Creek, Watts Bar, Hope Creek, Grand Gulf, Cooper, Sequoyah, Byron, Pilgrim, Arkansas Nuclear, Three Mile Island, Braidwood, Susquehanna, Summer, Prairie Island, Columbia, Seabrook, Brunswick, Surry, Limerick, North Anna, Turkey Point, River Bend, Vermont Yankee, Crystal River, Haddam Neck, Ginna, Diablo Canyon, Callaway, Vogtle, Waterford, Duane Arnold, Farley, Robinson, Clinton, South Texas, San Onofre, Cook, Comanche Peak, Yankee Rowe, Maine Yankee, Quad Cities, Humboldt Bay, La Crosse, Big Rock Point, Rancho Seco, Zion, Midland, Bellefonte, Fort Calhoun, FitzPatrick, McGuire, LaSalle, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant
Issue date:	03/31/1993
From:	Grimes B; Office of Nuclear Reactor Regulation
To:	;
References
	IN-93-023, NUDOCS 9303240274
	Download: ML031080024 (23)
	v • d • e

UNITED STATES

NUCLEAR REGULATORY COMMISSION

OFFICE OF NUCLEAR REACTOR REGULATION

WASHINGTON, D.C. 20555 March 31, 1993 NRC INFORMATION NOTICE NO. 93-23: WESCHLER INSTRUMENTS MODEL 252 SWITCHBOARD METERS

Addressees

All holders of operating licenses or construction permits for nuclear power

reactors. 7

Purpose

The U.S. Nuclear Regulatory Commission (NRC) is issuing this information

notice to alert addressees to possible problems with Weschler Instruments

(Weschler) Model 252 commercial grade switchboard meters. It is expected that

recipients will review the information for applicability to their facilities

and consider actions, as appropriate, to avoid similar problems. However, suggestions contained in this information notice are not NRC requirements;

therefore, no specific action or written response is required.

Description of Circumstances

On November 9, 1992, Weschler informed the NRC of sticking meter movements in

some Model 252 meters manufactured and supplied as commercial grade items.

Although Weschler reported having no evidence that meters manufactured

specifically for safety-related service are affected, Weschler was concerned

that affected commercial grade meters could have been dedicated for use in

nuclear safety-related applications.

Discussion

Weschler determined that some of the commercial grade meters returned for

repair or calibration were inaccurate and erratic. The vendor engineering

report attributed this problem to sticking of the meter movement because of an

off-center torsion spring. Weschler determined that this condition resulted

from a deviation in the dimensions associated with the torsion head screws

combined with several coincidental factors that included (1) degradation of

clip-to-torsion screw lubrication, (2) low initial force from the spring- retaining clip or fatigue of the spring-retaining clip, (3) variations in the

alignment of the meter movement during initial assembly, and (4) the effect of

the summation of the dimensional tolerances in the assembly of the

subcomponents.

9303240274 P P 5tC C* i\ 9I _X3 C9c

IN 93-23 March 31, 1993 To prevent this deficiency in future products, Weschler revised its production

inspection procedures to specifically require checking the dimensions in

question. Weschler also revised its nuclear quality assurance procedures to.

require specific checks of torsion head screw dimensions, although the vendor

has not detected a problem with meters manufactured specifically for safety- related applications.

Weschler could not determine whether or not any Model 252 switchboard meters

sold as commercial grade items through the various distributors had been

dedicated for use in nuclear safety-related applications. Therefore, Weschler

has not directly notified any licensees about this problem.

Weschler stated that the principal corrective action it has taken for affected

meters returned for repair and recalibration is to replace the faulty torsion

head screws because they can't be repaired. Upon request, Weschler will give

licensees information about the problem and the recommended corrective

measures.

This information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

the technical contact listed below or the appropriate Office of Nuclear

Reactor Regulation (NRR) project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contact: S. V. Athavale, NRR

(301) 504-2974 Attachment:

List of Recently Issued NRC Information Notices

K-I

Attachment

IN 93-23 March 31, 1993 LIST OF RECENTLY ISSUED

NRC INFORMATION NOTICES

Information Date of

Notice No. Subject Issuance Issued to

93-22 Tripping of Klockner- 03/26/93 All holders of OLs or CPs

Moeller Molded-Case for nuclear power reactors.

Circuit Breakers due to

Support Level Failure

93-21 Summary of NRC Staff 03/25/93 All holders of OLs or CPs

Observations Compiled for light water nuclear

during Engineering Audits power reactors.

or Inspections of Licen- see Erosion/Corrosion

Programs

93-20 Thermal Fatigue Cracking 03/24/93 All holders of OLs or CPs

of Feedwater Piping to for PWRs supplied by

Steam Generators Westinghouse or Combustion

Engineering.

93-19 Slab Hopper Bulging 03/17/92 All nuclear fuel cycle

licensees.

93-18 Portable Moisture-Density 03/10/93 All U.S. Nuclear Regulatory

Gauge User Responsibilities Commission licensees that

during Field Operations possess moisture-density

gauges.

93-17 Safety Systems Response 03/08/93 All holders of OLs or CPs

to Loss of Coolant and for nuclear power reactors.

Loss of Offsite Power

93-16 Failures of Nut-Locking 02/19/93 All holders of OLs or CPs

Devices in Check Valves for nuclear power reactors.

93-15 Failure to Verify the 02/18/93 All holders of OLs or CPs

Continuity of Shunt Trip for nuclear power reactors.

Attachment Contacts in

Manual Safety Injection

and Reactor Trip Switches

93-14 Clarification of 02/18/93 All licensees who possess

10 CFR 40.22, Small source material.

Quantities of Source

Material

OL = Operating License

CP - Construction Permit

~'-2 IN 93-23 March 31, 1993 To prevent this deficiency in future products, Weschler revised its production

inspection procedures to specifically require checking the dimensions in

question. Weschler also revised its nuclear quality assurance procedures to

require specific checks of torsion head screw dimensions, although the vendor

has not detected a problem with meters manufactured specifically for safety- related applications.

Weschler could not determine whether or not any Model 252 switchboard meters

sold as commercial grade items through the various distributors had been

dedicated for use in nuclear safety-related applications. Therefore, Weschler

has not directly notified any licensees about this problem.

Weschler stated that the principal corrective action it has taken for affected

meters returned for repair and recalibration is to replace the faulty torsion

head screws because they can't be repaired. Upon request, Weschler will give

licensees information about the problem and the recommended corrective

measures.

This information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

the technical contact listed below or the appropriate Office of Nuclear

Reactor Regulation (NRR) project manager.

orig /s/'d by BKGrimes

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contact: S. V. Athavale, NRR

(301) 504-2974 Attachment: % L *

List of Receitly Issudd NRC Information Notices

DOCUMENT NAME: 93-2IN

D/DRIL:NRR *D/DRCH:NRR *C/OGCB: DORS:NRR

CERossi BABoger GHMarcus

3 03/11/93 02/11/93 03/15/93

OGCB:DORS:NRR*HICB:DRCH:NRR*SC/HICB:DRCH:NRR*C/HICB:DRCH:NRR*RPB:ADM

AJKugler SVAthavale JMauck JWermiel TechEd

02/08/93 02/08/93 02/10/93 02/10/93 02/08/93

IN 93-XX

March XX, 1993 To prevent this deficiency in future products, Weschler revised its production

inspection procedures to specifically require checking the dimensions in

question. Weschler also revised its nuclear quality assurance procedures to

require specific checks of torsion head screw dimensions, although the vendor

has not detected a problem with meters manufactured specifically for safety- related applications.

Weschler could not determine whether or not any Model 252 switchboard meters

sold as commercial grade items through the various distributors had been

dedicated for use in nuclear safety-related applications. Therefore, Weschler

has not directly notified any licensees about this problem.

Weschler stated that the principal corrective action it has taken for affected

meters returned to it for repair and recalibration is to replace the faulty

torsion head screws because they can't be repaired. Upon request, Weschler

will give licensees information about the problem and the recommended

corrective measures.

This information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

the technical contact listed below or the appropriate Office of Nuclear

Reactor Regulation (NRR) project manager.

Brian K. Grimes, Director

Division of Operating Reactor Suppprt

Office of Nuclear Reactor Regulation

Technical contact: S. V. Athavale

(301) 504-2974 Attachment: List of Recently Issued NRC Information Notices

D/DORS:NRR *D/DRIL:NRR *D/DRCH:NRR C/OGCB:DORS:NRR

BKGrimes CERossi BABoger GHMarcu

03/ /93 03/11/93 02/11/93 / xi 9

OGCB:DORS:NRR*HICB:DRCH:NRR*SC/HICB:DRCH:NRR*C/HICB:DRCH:NRR*RPB:ADM

AJKugler SVAthavale JMauck JWermiel TechEd

02/08/93 02/08/93 02/10/93 02/10/93 02/08/93

-C

K>~ 1 IN 93-XX