View source for Information Notice 1993-96, Improper Reset Causes Emergency Diesel Generator Failures

{{Adams
| number = ML031060602
| issue date = 12/14/1993
| title = Improper Reset Causes Emergency Diesel Generator Failures
| author name = Grimes B
| author affiliation = NRC/NRR
| addressee name = 
| addressee affiliation = 
| docket = 05000003, 05000010, 05000029, 05000133, 05000155, 05000171, 05000206, 05000213, 05000219, 05000220, 05000237, 05000244, 05000245, 05000247, 05000249, 05000250, 05000251, 05000254, 05000255, 05000259, 05000260, 05000261, 05000263, 05000265, 05000266, 05000267, 05000269, 05000270, 05000271, 05000272, 05000275, 05000277, 05000278, 05000280, 05000281, 05000282, 05000285, 05000286, 05000287, 05000289, 05000293, 05000295, 05000296, 05000298, 05000301, 05000302, 05000304, 05000305, 05000306, 05000309, 05000311, 05000312, 05000313, 05000315, 05000316, 05000317, 05000318, 05000320, 05000321, 05000322, 05000323, 05000324, 05000325, 05000327, 05000328, 05000329, 05000330, 05000331, 05000333, 05000334, 05000335, 05000336, 05000338, 05000339, 05000341, 05000344, 05000346, 05000348, 05000352, 05000353, 05000354, 05000361, 05000362, 05000364, 05000366, 05000368, 05000369, 05000370, 05000373, 05000374, 05000382, 05000387, 05000388, 05000389, 05000390, 05000391, 05000395, 05000397, 05000400, 05000409, 05000410, 05000412, 05000413, 05000414, 05000416, 05000423, 05000424, 05000425, 05000437, 05000438, 05000439, 05000440, 05000441, 05000443, 05000444, 05000445, 05000446, 05000454, 05000455, 05000456, 05000457, 05000458, 05000461, 05000482, 05000483, 05000498, 05000499, 05000508, 05000528, 05000529, 05000530
| license number = 
| contact person = 
| document report number = IN-93-096, NUDOCS 9312080261
| document type = NRC Information Notice
| page count = 12
}}
{{#Wiki_filter:K>
                                     UNITED STATES

NUCLEAR REGULATORY COMMISSION

OFFICE OF NUCLEAR REACTOR REGULATION

WASHINGTON, D.C. 20555 December 14, 1993 NRC INFORMATION NOTICE 93-96:    IMPROPER RESET CAUSES EMERGENCY DIESEL

GENERATOR FAILURES

==Addressees==
All holders of operating licenses or construction permits for nuclear power

reactors.

- 

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

notice to alert addressees to the potential for an emergency diesel generator

(EDG) to fail to start on demand or to trip during operation due to improper

execution of the reset operation at the conclusion of the previous run. 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==

===H.B. Robinson===
  In August of 1987 at the H.B. Robinson plant, startup trips occurred on the

KA" EDG. With the assistance of a vendor representative, several steps were

taken in an effort to preclude such trips, including replacement of the

governor, replacement of the governor oil, replacement of sticky fuel

injection pumps, checking of injection pump timing, and rebalancing fuel rack

settings. In February of 1988, startup trips were again experienced. It was

concluded, after detailed inspection of the latch mechanism parts, that there

was a possibility of wear on the tip of the latch, which may have been a

contributing factor to the trips. These parts were replaced with new parts.

On June 3, 1992, during the performance of a test activity, the TAw EDG

tripped on mechanical overspeed after the engine had been operating

approximately one half hour. After detailed consideration of possible

scenarios for the trips and considering prior actions taken, it was determined

that the most probable cause was a failure to properly reset the trip

mechanism after the previous run. It was concluded that operations personnel

apparently were unaware of the importance of moving the reset lever through

its full travel. In addition, resettirg was difficult for shorter individuals

due to the location of the reset lever, which is positioned over the exhaust

9312080261        PbR         ZtE           N       o cq;     q         1s (tat

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<-N 93-96 December 14, 1993 manifold. Operations personnel were subsequently trained on the proper method

for actuating the reset lever. Also, a step was provided to permit easier

access to the lever.

Duane Arnold

On June 11, 1993, while the Duane Arnold plant was operating at 85 percent of

full power, the 'A" EDG tripped approximately 3 seconds after the initial

start signal during an operability surveillance test. An evaluation was

conducted by the licensee of possible EDG trip causes, including occurrence of

an actual overspeed condition, failure of the overspeed mechanism, actuation

of the emergency stop pushbutton, failure of the emergency stop pushbutton, latch assembly not fully latched, latch assembly failure, mechanical trip

mechanism failure, and annunciator circuit or trip lever microswitch failure.

It was concluded that the most probable cause of the trip was that the latch

--assembly was not fully engaged from the previous reset operation and engine

startup vibration unlatched the trip mechanism. Less than complete engagement

of the latch assembly could be caused by an inadequate reset operation.

Corrective actions adopted by the licensee included procedure revisions to

ensure a more positive latching operation, improved physical access to the

reset lever, and operator training.

The procedure revision directs operators to perform the reset operation a

second time following the initial resetting of the trip. The second reset is

somewhat easier to perform and should ensure that the latch is fully engaged

in the event that the initial latching sequence resulted in a partially

latched condition. Verification that the latch is fully seated is

accomplished by checking that the reset lever subsequently moves freely.

Discussion

In response to experience with previous trips during fast starts, the diesel

manufacturer for both plants, (Coltec/Fairbanks Morse Engine Division), had

previously issued a service information letter (SIL, Volume A, Issue 25, dated

August 1, 1991) addressing a revised overspeed trip adjustment. The SIL

recommended that the overspeed trip setting be raised from the range of 112 to

115 percent to the range of 115 to 117 percent. In light of events that

occurred at H.B. Robinson and Duane Arnold, the manufacturer has now advised

these licensees that proper resetting of the trip mechanism would be enhanced

by slowly moving the reset lever fully to the reset position and back, twice.

The inadvertent partial reset latching operations described above may also

occur on other units having similar mechanical trip mechanisms.

- IN 93-96 December 14, 1993 This notice requires no specific action or written response. If you have any

questions about the information in this notice, please contact one of the

technical contacts 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 contacts:  Larry Garner, RII

(404) 331-4663 Chris G. Miller, RIII

(319) 851-5111 Walter P. Haass, NRR

(301) 504-3219 Attachment:

===List of Recently Issued NRC Information Notices===

Att'achment

IN 93-96 December 14, 1993 LIST OF RECENTLY ISSUED

NRC INFORMATION NOTICES

Information                                  Date of

Notice No.             Subject                Issuance    Issued to

Storm-Related Loss of          12/13/93   All holders of OLs or CPs

Offsite Power Events                      for nuclear power reactors

due to Salt Buildup                       located close to a large

on Switchyard Insulators                  body of salt water.

Unauthorized Forced            12/09/93   All holders of OLs or CPs

Entry into the Pro-                       for nuclear power reactors.

tected Area at Three

Mile Island Unit 1 on

February 7, 1993
  93-93          Inadequate Control of          12/08/93   All holders of OLs or CPs

Reactor Coolant System                    for nuclear power reactors.

Conditions During Shutdown

93-92          Plant Improvements to          12/07/93   All holders of OLs or CPs

Mitigate Common Depend-                   for nuclear power reactors.

encies in Component

Cooling Water Systems

91-21,         Inadequate Quality             12/07/93   All holders of OLs or CPs

Supp. 1        Assurance Program of                      for nuclear power reactors

Vendor Supplying                          and all recipients of

Safety-Related Equipment                  NUREG-0040, license Con- tractor and Vendor Inspec- tion Status Report' (White

Book).

89-77,         Debris in Containment         12/03/93    All holders of OLs or CPs

Supp. 1        Emergency Sumps and                       for nuclear power reactors.

Incorrect Screen

Configurations

93-91          Misadjustment Between         12/03/93    All holders of OLs or CPs

General Electric 4.16-KV                  for nuclear power reactors.

Circuit Breakers and Their

Associated Cubicles

. OL = Operating License

CP - Construction Permit

IN 93-96 December 14, 1993 This notice requires no specific action or written response. If you have any

questions about the information in this notice, please contact one of the

technical contacts 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 contacts:     Larry Garner, RII

(404) 331-4663 Chris G. Miller, RIII

(319) 851-5111 Walter P. Haass, NRR

(301) 504-3219 Attachment:

===List of Recently Issued NRC Information Notices===
*SEE PREVIOUS CONCURRENCE

OFFICE    VIB/DRIL*    lREGION III*    REGION II*   VIB/DRIL*     VIB/DRIL*
  NAME      WHaass         CHiller       LGarner      UPotapovs     LNorrholm

DATE      09/09/93       09/09/93      08/30/93     09/10/93      09/15/93 TECH ED*     DRIL/NRR*    EEKB/NRR*    OGCB/DORS*  1C:OGCB/DORS*    D:      N

I

DGable       CERossi      CBerlinger   PCWen         GHMarcusl

12/7/93
  09/14/93- 09/20/93 OFIICIAL   ---      U~
                            10/21/93 KJUL4 4NL       s~~r 11/16/93
                                         11/10/93 OFFICIAL RECORD    COPY      WULUMMNT NAME:  VJ-V0.1N

IN 93-XX

December xx, 1993 This notice requires no specific action or written response. If you have any

questions about the information in this notice, please contact one of the

technical contacts 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 contacts:     Larry Garner, RII

(404) 331-4663 Chris G. Miller, RIII

(319) 851-5111 Walter P. Haass, NRR

(301) 504-3219 Attachment:

===List of Recently Issued NRC Information Notices===
*SEE PREVIOUS CONCURRENCE

OFFICE

NAME

DATE

VIB/DRIL*
           WHaass

09/09/93 REGION III*
                          CMiller

09/09/93 REGION II*
                                              LGarner

08/30/93 IVIB/DRIL*
                                                            UPotapovs

09/10/93 lVIB/DRIL*
                                                                         LNorrholm

09/15/93 TECH ED*    DRIL/NRR*   FEEKB/NRR*          OGCB/DORS*    C:OGCB DORS* lD:DORS/NRR

DGable      CERossi      CBerlinger         PCWen         GHMarcus       BKGrimes

09/14/93    09/20/93      10/21/93          11/10/93      11/16/93        12/ /93 UIIILIRL nrLLUrU  Luryv      UULrIs~r~II slaver.  1NrrubrT.wen..._
MtLUAL    KtLUKU LUFT        00CUMEN1 NAME:       Mtubbl.wen

IN 93-XX

November xx, 1993 This notice requires no specific action or written response. If you have any

questions about the information in this notice, please contact one of the

technical contacts 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 contacts:      Larry Garner, RII

(404) 331-4663 Chris G. Miller, RIII

(319) 851-5111 Walter P. Haass, NRR

(301) 504-3219 Attachment:

===List of Recently Issued NRC Information Notices===
                                       r III

*SEE PREVIOUS CONCURRENCE             .1, OFFICE     VIB/DRIL*     REGION I*             REGION II*     VIB/DRIL*     VIB/DRIL*
  NAME      WHaass          CMiller              LGarner        UPotapovs     LNorrholm

DATE       09/09/93    109/09/93               08/30/93       09/10/93       9/15/93 TECH ED*     DRIL/NRR*     EEKB/NRR*            OGCB/DORS*     C:OGCB/DORS    D:DORS/NRR

DGable       CERossi       CBerlinger           PCWen          GHMarcu l r- BKGrimes t

09/14/93     09/20/93      10/21/93             11/10/93       11/16/93       11/ /93
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IN 93-XX

October xx, 1993 This notice requires no specific action or written response. If you have any

questions about the information in this notice, please contact one of the

technical contacts 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 contacts:          Larry Garner, R11
                             (404) 331-4663 Chris G. Miller, RIII

(319) 851-5111 Walter P. Haass, NRR

(301) 504-3219 Attachment:
1. List of Recently Issued Information Notices

*SEE PREVIOUS CONCURRENCE

OFFICE    VIB/DRIL*        REGIONX*         REGION II*   VIB/DRIL*     VIB/DRIL*
  NAME     WHaass           CMiller          LGarner      UPotapovs      LNorrholm

DATE     09/09/93         09/09/93         08/30/93     09/10/93      09/15/93 TECH ED*     DRIL/NRR* l EEKB/NRR*         lOGCB/DORS    C:OGCB/DORS     D:DORS/NRR

DGable       CERossi        CBerlinger       PCWen 1 0l  GHMarcus        BKGrimes

09/14/93     09/20/93       10/21/93       111/10/93     11/  /93        11/      /93

===OFFICIAL RECORD COPY===
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IN 93-XX

October xx, 1993 This notice requires no specific action or written response. If you have any

questions about the information in this notice, please contact one of the

technical contacts 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 contacts:     Larry Garner, RII

(404) 331-4663 Chris G. Miller, RIII

(319) 851-5111 Walter P. Haass, NRR

(301) 504-3219 Attachment:
1. List of Recently Issued Information Notices

*SEE PREVIOUS CONCURRENCE

OFFICE  VIB/DRIL*    REGION I*    REGION II*    VIB/DRIL*     VIB/DRIL*
  NAME    WHaass       CMiller      LGarner       UPotapovs     LNorrholm

DATE    09/09/93     09/09/93     08/30/93    1 09/10/93      09/15/93 TECH ED*   DRIL/NRR*  JEEKB/NROM OGCB/DORS       C:OGCB/DORS    D:DORS/NRR

DGable    CERossi     CBerlinger   PCWen        GHMarcus       BKGrimes

09/14/93 09/20/93     10/13/93     10/   /93    10/  /93       10/   /93

===OFFICIAL RECORD COPY===
DOCUMENT NAME: INEDGST.wen

IN 93-XX

October xx, 1993 Discussion

The staff is continuing its review of the above events with the manufacturer

of the diesel engines, Coltec/Fairbanks Morse Engine Division, to arrive at a

more detailed and consistent set of procedures to assure a positive latching

operation. In addition, it should be noted that other diesel engine

manufacturers may have similar mechanical trip mechanisms, and licensees

should be aware that potential inadvertent partial reset latching operations

may also occur on those units.

This notice requires no specific action or written response. If you have any

questions about the information in this notice, please contact one of the

technical contacts 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 contacts:                           Chris G. Miller, RI at Duane Arnold

(319) 851-5111 Larry Garner, R11
                                                         (404) 331-4663 Walter P. Haass, NRR

(301) 504-3219 Attachment:
         1. List of Recently Issued Information Notices

* SEE PREVIOUS CONCURRENCE

OFFICE     VIB/DRIL                               REGION I                                      REGION II                             VIB/DRIL                   VI5/YOL

NAME       WHaass                                CMiller                                        LGarner                               UPotapovs                 1; R        holm

DATE           9 / 9/93*                               9/9/93*                                     8/30/93*                                9/10/93*           l    C//) /93 COPY       YES                         NO        YES                              NO            YES                      NO           YES               NO      6                  NO

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DATE          )p               /93         1 61A/93                                  / /93                                     /          /93               /       /93 COPY       YES                    NO      YES          NO                 YES                            NO       YES                          NO      YES                NO

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IN 93-XX

October xx, 1993 Page.4 of 3 Attachment:
         1. List of Recently Issued Information Notices

*   SEE PREVIOUS CONCURRENCE

OFFICE   VIB/DRIL              REGION I           REGION II          VIB/DRIL            VIB/DRIL

NAME     WHaass                CMiller            LGarner            UPotapovs           LNorrholm

DATE        9 / 9/93*            9/9/93*             8/30/93*           9/10/93*           /   /93 COPY     YES          NO       YES           NO   YES           NO   YES          NO     YES       NO

DOC

OFFICE   TECH EDITOR     DRIL/NRR        OGCB/NRR             EELB/NRR           DORS/NRR

NAME      a  44,         CERossi         GMarcus              CBerlinger         BGrimes

DATE      7 /     9          /   /93          /  /93               /   /93           /    /93 COPY     YES      NO     YES     NO      YES            NO    YES          NO   YES          NO

DOC

U-II                  IEODCP                   DouetNm:G\NDS

OFFICIAL RECORD COPY                              Document Name: G:\INEDGST

IN 93-XX

October xx, 1993 Discussion

The staff is continuing its review of the above events with the manufacturer

of the diesel engines, Coltec/Fairbanks Morse Engine Division, to arrive at a

more detailed and consistent set of procedures to assure a positive latching

operation. In addition, it should be noted that other diesel engine

manufacturers may have similar mechanical trip mechanisms, and licensees

should be aware that potential inadvertent partial reset latching operations

may also occur on those units.

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

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

one of the technical contacts 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 contacts:         Chris G. Miller, RI at Duane Arnold

(319) 851-5111 Larry Garner, RII

(404) 331-4663 Walter P. Haass, NRR

(301) 504-3219                                                                                  a.?

Attachment:
         1. List of Recently Issued Information Notices                                                                    ' 1-eCL

OFFICE    VIBDRIL                       E                                                     VIBD                         VIB/DRIL

NAME      WHaass                          F 4It                  _f arneamfil   r A           UPot          V              LNorrholm

DATE           9/?9//93
                    9/93                           93                         /      /93                     93/                   /93 COPY      Y               NO        E                    NO        Y                    NO    YE                    NO     YES       NO

D o c_     _   _ _  _ _ _ _ _ _   _  _    _  _ _   _   _  _   _    _    _   _   _ _  _ _   _ _ _  _   _   _   _   _   _ _  _ _ _ _ _ _  _  _
OFFICE    DRIL/NRR               OGCB/NRR                          EELB/NRR                   DORS/NRR

NAME      CERossi                GMarcus                           CBerlinger                 BGrimes

DATE            I /93                     I /93                             I     /93                 I       /93 COPY      YES             NO     YES                     NO        YES                  NO    YES                   NO

DO

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MFICIAL RECORD COPY                                              Document Name: 6:\INEUGST}}

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