Information Notice 1985-49, Relay Calibration Problem

Relay Calibration Problem

ML031180261
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, 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, 05000000, Zimmer, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant, Skagit, Marble Hill, Crane
Issue date:	07/01/1985
From:	Jordan E NRC/IE
To:
References
IN-85-049, NUDOCS 8506260654
Download: ML031180261 (3)

SSINS NO.:

6835 IN 85-49

UNITED STATES

NUCLEAR REGULATORY COMMISSION

OFFICE OF INSPECTION AND ENFORCEMENT

WASHINGTON, D.C.

20555

July 1, 1985

IE INFORMATION NOTICE NO: 85-49:

Addressees

All nuclear power reactor facilities holding an operating license (OL) or a

construction permit (CP).

Purpose

This information notice provides information on a potentially significant

problem pertaining to relay orientation during calibration and operation.

It

is expected that recipients will review the information for applicability to

their facilities and consider actions, if appropriate, to preclude a similar

problem occurring at their facilities.

However, suggestions contained in this

information notice do not constitute NRC requirements; therefore, no specific

action or written response is required.

Discussion:

South Carolina Electric and Gas Company, at the Summer nuclear power plant, recently discovered that there was a significant error in the calibration of

several E-7000 series Agastat time-delay relays.

The licensee's procedure for

replacement of Agastat timing relays did not require calibration of these

relays in the installed position.

During relay replacement, these time-delay

relays were "bench" calibrated in a horizontal position, then field mounted in

a vertical orientation.

Subsequent time-delay measurements determined that the

delay times of the installed devices were as much as 30% greater than that

established during "bench" calibration.

Licensee investigation of this anomaly determined that the manufacturer's data

sheet for installation and operation of these relays identifies a potential for

the observed calibration error.

This data sheet states that a dial calibration

error may result if the device is mounted horizontally without the manufacturer's

supplied horizontal operation options.

Because these relays were mounted

vertically at this facility, the potential for error as a result of horizontal

"bench" calibration was overlooked.

Because of this oversight, the licensee's

relay replacement procedure did not specify device orientation during calibration.

Several of these relays were functionally arrayed (sequentially or in parallel)

in safety-related applications, such as in the emergency diesel generator under- voltage start circuitry.

The above identified time-delay error went undetected

for a period of approximately 4 months for some of these relays.

This occurred

because the licensee's replacement procedure specified only an operational or

functional postmaintenance test of the system containing the relays.

This method

of testing did not detect the individual relay time-delay calibration errors.

8506260654

I- ,

IN 85-49 July 1, 1985 The licensee has subsequently revised their relay calibration procedures to

calibrate or check the calibration of relays after mounting in place, where

practical.

The procedures were also revised to ensure "bench" calibrations

are performed in the same orientation as mounted, where applicable.

Personnel

involved in relay calibration have received training on the revised procedures.

No specific action or written response is required by this information notice.

If you have any questions about this matter, please contact the Regional

Administrator of the appropriate NRC Regional Office or this office.

44a

Director

Divisio

f Emergency Preparedness

and Engineering Response

H. Bailey, IE

(301) 492-9006 Attachment:

Attachment 1

IN 85-49

July 1, 1985

LIST OF RECENTLY ISSUED

IE INFORMATION NOTICES

Information

Date of

Notice No.

Subject

Issue

Issued to

85-48

85-47

85-46

85-45

85-44

85-43

85-42

85-41 Respirator Users Notice:

Defective Self-Contained

Breathing Apparatus Air

Cylinders

Potential Effect Of Line-

Induced Vibration On Certain

Target Rock Solenoid-Operated

Valves

Clarification Of Several

Aspects Of Removable Radio- active Surface Contamination

Limits For Transport Packages

6/19/85

6/18/85

6/10/85 Potential Seismic Interaction 6/6/85 Involving The Movable In-Core

Flux Mapping System Used In

Westinghouse Designed Plants

All power reactor

facilities holding

an OL or CP, research, and test reactor, fuel cycle and

Priority 1 material

licensees

All power reactor

facilities holding

an OL or CP

All power reactor

facilities holding

an OL

All power reactor

facilities holding

an OL or CP

All power reactor

facilities holding

an OL

All power reactor

facilities holding

an OL or CP

All power reactor

facilities holding

an OL or CP

All power reactor

facilities holding

a CP

Emergency Communication

System Monthly Test

Radiography Events At Power

Reactors

Loose Phosphor In Panasonic

800 Series Badge Thermo- luminescent Dosimeter (TLD)

Elements

Scheduling Of Pre-Licensing

Emergency Preparedness

Exercises

5/30/85

5/30/85

5/29/85

5/24/85 OL = Operating License

CP = Construction Permit