ML18054B432

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Forwards Operability Determination for Viking Connector Instrumentation Circuits,Per Insp Rept 50-255/90-05. Subj Connectors Expected to Be Replaced During 1990 Spring Maint Outage.Operability Determination Info Encl
ML18054B432
Person / Time
Site: Palisades Entergy icon.png
Issue date: 02/06/1990
From: Berry K
CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NUDOCS 9002220482
Download: ML18054B432 (13)
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  • consumers Power POWERiNii MICHlliAN'S PRDliRESS General Offices: 1945 West Parnell Road, Jackson, Ml 49201 * (517) 788-1636 Kenneth W Berry Director Nuclear Licensing February 6, 1990 Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 DOCKET 50-255 - LICENSE DPR PALISADES PLANT -

EEQ FOLLOW-UP INSPECTION, OPERABILITY DETERMINATION As a result of the EEQ followup inspection (90-005), the NRC requested additional information regarding Consumers Power Company's basis for qualification of Viking potted connectors. Consumers Power Company submitted the additional information, off the docket, on January 31, 1990.

On February 1, 1990 a telecon was held between NRR, Region III and Consumers Power Company to discuss the submitted information. The NRC determined that Consumers Power Company had not shown qualification for the Viking potted connectors and that Consumers Power Company should submit on the docket an operability determination for (1) Viking connector instrumentation circuits by noon on February 6, 1990 and (2) for Vi~ing connector control circuits by the end of the work day on February 7, 1990.

The attached operability determination for Viking connector instrumentation circuits is a detailed breakdown of what instrumentation goes through the potted Viking connectors.and the functions of the instrumentation. Also included is a discussion how the safety functions provided by the instruments inside containment with potted penetration connectors will be achieved to maintain the reactor in a .~afe condition. This operability determination has been reviewed and approved by the Plant Review Committee and found not to involve an unreviewed safety question.

The final resolutions of this issue will be the replacement of all Viking Industry potted connectors. Every effort will be made to complete all replace-ments during the 1990 Spring Maintenance Outage. A specific replacement schedule will be submitted to the NRC by March 1, 1990. The additional time is needed to allow us to determine replacement parts availability, engineering and construction resources, and to complete our evaluation of the circuit functions and prioritize replacement. Those that can not be replaced during the Spring Maintenance Outage will be replaced during the subsequent REFOUT.

OC0290-0003-NL02

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9002220482 900206 PDR ADOCK 05000255 A CMS ENERGY COMPANY .

~ PNU

.. 2 Nuclear Regulatory Commission Palisades Plant EEQ Followup Inspection February 6, 1990 Consumers Power company is continuing to improve the EEQ program. In 1989 a contractor completed an overview of the pr9grams and Consumers Power Company is evaluating several program enhancements. Consumers Power Company is also formulating a program that would result in a walkdown of all EEQ equipment to verify the accuracy of the files.

Kenneth W Berry Director, Nuclear Licensing CC Administrator, Region III, USNRC NRC Resident Inspector - Palisades Attachment

  • OC0290-0003-NL02

ATTACHMENT Consumers Power Company Palisades Plant Docket 50-/55 NRC NOTIFICATION DETERMINATION SAFETY REVIEW/EVALUATION

  • OC0290-0003-NL02 10 Pages

PALISADES NUCEAR PLANT Proc No 3.07 NRC NOTIFICATION DETERMINATION Attachment 2 Revision 4 Page 1 of 1 Item To Be Evaluated: Operability of Item Identification:

Instrumentation Circuits With Viking Potted Connectors Inside Containment No N/A Rev SECUON I *Yes No

1. Will the probability of an accident previously evaluated 1n the x FSAR be increased?
2. Will the consequences of an accident previously evaluated 1n the x FSAR be increased?
3. Will the probability of malfunctions of equipment important to x safety be increased?
4. Will the consequences of a malfunction of equipment important to x safety be increased?
5. Will the possibility of an accident of a different type than any x previously evaluated in the FSAR be created?
6. Will the possibility of a malfunction of a different type than x any previously evaluated in the FSAR be created?

/

Will the margin of safety as defined 1n the basis for any x Technical Specification be reduced?

If any of the above questions are answered Yes, an unreviewed safety question 1s involved. A written Safety Analysis shall be prepared and the item shall not be implemented without prior NRC concurrence.

If all of the above questions are answered No, a written Safety Analysis shall be prepared to provide the documented basis for concluding the proposed item does not constitute an unreviewed safety,question.

SECTION II

1. Should this be included in an FSAR update? x
2. Is prior NRC approval and/or an application for amendment to the x Palisades Operating License required?

SECTION III Paul J Sondgerath I 2/06/90 Robert A Vincent I 2/06/90 Prepared By Date Reviewed By Date VIKING POTTED CONNECTORS-TC07

PALISADES NUCEAR PLANT Proc No 3.07 SAFETY REVIEW Attachment 2 Revision 4 Page 1 of 1 Item To Be Evaluated: Operability of Item Identification:

Instrumentation Circuits With Viking Potted Connectors Inside Containment No NA Rev Yes No

1. Does the item involve a change to procedures as described in the FSAR? x FSAR Sections affected _N_o_n~e___________________

FSAR Sections reviewed Reviewed the FSAR Index

2. Does the item involve a change to the facility as described in the FSAR? and Appendix 7C FSAR Sectio,ns affected Sections 1.8.6, 5.1.4.10, 8.1.3, 5.2.2.7 x FSAR Sections reviewed Reviewed the FSAR Index
3. Does the item involve a test or experiment not described in the FSAR? x FSAR Sections affected None

~~~~~~~~~~~~~~~~~~~~~-

FSAR Sections reviewed Reviewed FSAR Index

~~~~~~~~~~~~~~~~~~~~~-

4. Does the, item req~ire a change to the Technical Specification?

TS Sectfons affected None

~~~~~~~~~~~~~~~~~~~~~~-

x TS Sections reviewed Reviewed Tech Spec Index and Section 3.17 NOTE:

This Safety Evaluation is written to address the environmental qualification concern Viking potted connectors inside containment. This concern was raised by NRC inspectors during an EEQ inspection. Although there is not a physical change to the Facility involved here, question two is marked "yes" since the FSAR sections listed ar the ones which describe the qualification program at Palisades, and since the qualifi-cation of the Viking potted connectors per the FSAR description is in question.

If any Safety Review question listed above is answered Yes, perform a written Safety Evaluation according to Section 5.3.

If all Safety Review questions listed above are answered No, a written Safety Evaluation is not required. However, this Attachment shall accompany other documentation for the item being evaluated in order to provide documentation that a Safety Evaluation was not required.

Paul J Sondgerath I 2/06/90 Robert A Vincent I 2/06/90 Prepared By Date Reviewed By Date POTTED CONNECTORS-TC07

1.. The probability of an accident previously evaluated in the FSAR will not be i"ncreased. The concern raised is that of the degree of insulation degradation the potted connectors suffer during an accident. Since the insulation resistance is not degraded during normal operation the probability of an accident previously evaluated in the FSAR is not increased.

The consequences of an accident previously evaluated in the FSAR will not be increased. The attached analysis describes how the safety related functions of the associated instrument circuits are still achieved even if the insulation resistance of the connector decreases beyond that previously expected. Since these safety functions are still achieved the consequences of an accident previously evaluated in the FSAR are not increased.

3. The probability of malfunctions of equipment important to safety will not be increased. As described in the attached analysis, the actions required by the affected instruments are achieved either early in the accident before large errors are experienced or by redundant instrumentation. Since the required safety functions are still achieved the probability of a malfunction of equipment important to safety is not increased.
4. The consequences of a malfunction of equipment important to safety is not increased. The attached analysis describes how the safety related functions provided by the affected instruments are achieved before large instrument errors are experienced. Since the safety related functions are still achieved, the consequences of a malfunction of equipment important to safety have not been increased.

5* The possibility of an accident of a different type than those previously

.evaluated will not be created. The insulation resistance degradation of the connectors does not occur until after the connector environment becomes harsh.

Since this ~appens after the accident has started, and since the connectors are not in a degraded condition prior to the onset of an accident, the possibility of an accident of a different type is not created. In addition, the safety functions provided by the affected instruments (see attached analysis) will still be achieved and hence no new accident type will be created.

6. The possibility of a malfunction of a different type than any previously evaluated will not be created. The attached analysis describes how the safety functions provided by the affected instruments will still be achieved. Since these safety functions are still achieved the possibility of a malfunction of a different type is not created.
7. The margin of safety as defined in the basis for any technical specification will not be reduced. The attached analysis describes how the safety related functions for the affected equipment are achieved for a LOCA or MSLB. Since the safety functions assumed in the LOCA and MSLB analyses will still be achieved the margin of safety as defined in the Tech Specs will not be reduced.

POTTED CONNECTORS-TC07

OPERABILITY OF INSTRUMENTATION CIRCUITS WITH POTTED CONNECTORS INSIDE CONTAINMENT Written By/Date: Paul J Sondgerath' 02/06/90 Ops Review/Date: Richard L Massa 02/06/90 Tech Review/Date: Michael A Ferens 02/06/90 I. OBJECTIVE This is written to show how the functions provided by instruments inside containment with potted penetration connectors will be achieved, if the connectors degrade during a design basis accident and cause instrument errors greater than those previously expected.

II. REFERENCES A. Schematics E-62 Sh 3E E-96 Sh 6 E-78 Sh 1 E -78 Sh lA E-83 Sh 3 E-238 Sh 1.

E-211 Sh 1 E-238 Sh lA E-211 Sh lA E-84 Sh 2 E-84 Sh 5 E-84 Sh 7

  • III ANALYSIS INPUT E-1016 Sh 1 E-1016 Sh 2 The referenced schematics and applicable sections of the FSAR provide the input for this analysis. The connectors addressed here will not fail during an accident but only degrade during the harsh portion (high temperature) of the event. The qualification test for the Viking potted connectors shows that the connectors will not fail catastrophically during an accident, but since insulation resistance values were only taken at the end and at the beginning of the test (not during) the performance of the connector during the event cannot be quantified with respect to IR value.

IV. ASSUMPTIONS The insulation resistance losses may go higher than currently considered thereby inducing instrument errors larger than those calculated in the existing error analysis. This degraded condition will only exist during periods of high containment temperature during an accident. All actuation functions will take place early in the transient (reactor trip, AFAS, etc) and therefore will not be affected.

MI0290-008A-TC07 Page 1 of 7

The safety related functions provided by each of the affected instruments was reviewed in detail. Per discussions with operations and accident analysis personnel it was concluded that most of the safety related functions provided by these instruments occur within S seconds of the onset of a LOCA or MSLB. The exceptions to this were the following functions:

PT-01048 - Interlock for M0-3016

- Input into LTOP PT-01028,D - High Pressure Trip

- TM/LP Trip for Small Break LOCA Acoustical Monitors - Relief Valve Position Indication The interlock for M0-3016 can be jumpered out by a temporary mod per operating Procedure SOP-3. Enabling of the LTOP system is not required until late in the accident when the containment temperature has decreased and the insulation resistance of the connectors will have returned to near normal conditions. The analyzed events which assume the use of the relief valve acous-tical monitors and the pressurizer high pressure trip do not result in a degraded containment environment.

Therefore the effect on the connector insulation resis-tance is negligible. Since the environment for a small break LOCA is less harsh, the PT-01028, D transmitters will still provide the TM/LP trip.

In addition, although it cannot be quantified without extensive analysis, the size (with potting compound) and location of the connectors would provide some thermal lag in which the temperature seen by the internals of the connector would be delayed, thereby delaying the degradation of the connector insulation resistance.

Therefore the errors experienced while the instruments are performing their safety functions should be within the present EEQ error analysis. The error typically associated with a transmitter is +/-10%. The error associated with connectors in general in which test data is available is typically less than +/-2%. It can be seen that the error attributable to the connector is small in comparison to the error introduced by the transmitter.

V. ANALYSIS The first step in this analysis was to determine which instrument circuits inside containment have the Viking potted connectors. To accomplish this the current list of EEQ equipment was compared against the table in E-48 Sh 6DR. This table lists EEQ equipment and what type of connector it has. For EEQ equipment which was not MI0290-008A-TC07 Page 2 of 7

listed on this table the containment penetration connnection diagrams and vendor drawings were used to determine the type of connector. This review revealed that the following EEQ instrument circuits go through potted connectors:

EQUIP ID CANISTER/CONNECTOR TE-0122H8 Z-243/2 TE-0122C8 Z-243/2 TE-0112H8 Z-243/2 TE-0112C8 Z-243/2 LT-07510 Z-246/6 LT-07520 Z-246/6 PT-07510 Z-246/6 PT-07520 Z-246/6 PT-01028 Z-243/2 PT-01020 Z-246/8 PT-01048 Z-243/6

/ FE-1039 Z-142/4 FE-1040 Z-142/5 FE-1041 Z-142/6 FE-10428 Z-142/7 FE-10438 Z-142/8 The following discussions describe the functions of the equipment listed above and how the functions of this equipment would still be achieved for a 08A.

TE-0112C8, TE-011288, TEMPERATURE ELEMENTS FOR PCS LOOP COLD LEG TE-0122C8, TE-012288 AND HOT LEG CHANNEL B These temperature elements provide the following functions:

D 11 Input primary coolant temperature to Channel 811 TM/LP D

Input to temperature indicators in the control room (Tl's - 0112C8 I 011288 I 0122CB I 0122H8)

D Input to Critical Functions Monitor System (CFMS)

(CFMS is not a safety function.)

MI0290-008A-TC07 Page 3 of 7

  • TM/LP is not needed after the reactor trip which happens immediately in the accident. Indication is provided by three other redundant channels which do not use Viking potted connectors. Operators use indication provided by these instruments for trend-ing and are not required to take action based on a specified value provided by this indication. Opera-tors are cautioned in the EOP's not to rely on any single instrument to take actions. In addition the use of the in-core thermocouples may also be used to monitor PCS temperature. Based on this discussion the functions provided by these temperature elements will still be achieved.

LT-07510 AND LT-07520 STEAM GENERATOR LEVEL TRANSMITTERS These transmitters measure steam generator level to provide the following functions:

0 Input to level indicators in the control room (LI-0751D/LI-0752D) 0 Input to Auxillary Feedwater Actuation System (D Channel) 0 Input to S/G low level reactor trip units 0

CFMS (non-safety function)

The actuation functions (AFAS, RPS) are performed early in the accident and the connector will not have degraded to a level which would impede accomplishment of these functions. In addition, there are three redundant channels (LT-0751A, B, C and LT-0752A, B, C) which will also accomplish these functions along with indication which do not use Viking potted con-nectors. Operators use indication provided by these instruments for trending and are not required to take action based on a specified value provided by this indication. The operators are cautioned in EOP's not to rely on any single instrument to take actions. Based on this discussion the functions provided by these transmitters will still be achieved *

  • MI0290-008A-TC07 Page 4 of 7

PT-07510 AND PT-0752D STEAM GENERATOR PRESSURE TRANSMITTERS These transmitters provide the following functions:

0 Input to pressure indicating controllers which input to the steam generator low pressure 2/4 logic for MSIV closure.

0 Input to S/G low pressure reactor trip units Actuation functions provided by these transmitters are accomplished early in the accident and the con-nector will not have degraded to a level which would impede accomplishment of these functions. In addi-tion there are three redundant channels (PT-0751 A, B, C and PT-0752 A, B, C) which will also accomplish these functions along with indication which do not use Viking potted connectors. Operators use indica-tion provided by these instruments for trending and are not required to take action based on a specified value provided by this indication. The operators are cautioned in th~ EOP's not to rely on any single instrument to take actions. Based on this discussion the functions provided by these transmitters will still be achieved.

PT-01048 PRESSURIZER NARROW RANGE PRESSURE TRANSMITTER This transmitter provides the following functions:

0 Interlock for opening M0-3016 for lining up shutdown cooling with the PCS 0

Input into variable Low Temperature Over-pres surization Protection (LTOP) 0 Input to PTR-0125 Operating Procedure SOP-3 allows the use of a tempor-ary modification if the interlock feature for M0-3016 is not functional. The temporary modification places a jumper accross the contacts on PS-01048 to allow M0-3016 to be opened even though the instrument loop or PS-01048 is failed high. LTOP is not required until long after the initiating event and the condi-tion of the connector will have returned to near-before accident conditions.

MI0290-008A-TC07 Page 5 of 7

Indication will be provided by the wide range pressure transmitters and redundant transmitter PT-0104A. PTR-0125 is used for recording, no control function. Based on this discussion the functions provided by this transmitter will be achieved.

PT-01028 AND PT-01020 PRESSURIZER PRESSURE SAFETY INJECTION TRANSMITTERS These pressure transmitters provide the following functions:

0 Input to RPS High Pressure Trip Units 0

Input to Thermal Lo Pressure Trip Unit 0

Safety Injection Signal 0

Input to PORV Actuation Logic The FSAR relies on the containment high pressure signal, not pressurizer low pressure for SIS actua-tion in both the large break LOCA and the main steam line break accidents. Reactor trip is not credited in the LOCA analysis and the trip occurs on low S/G pressure for the MSLB. Therefore the pressurizer pressure transmitters play no part in the mitigation of the analyzed events. The high pressure trip fea-ture is only required in events where the containment environment would not be harsh and therefore the con-nector insulation resistance would not degrade (ie loss of external load, loss of feedwater).

These transmitters are used for SIS actuation for a small break LOCA. In the case of small break LOCAs (SBi..oCA) which do rely on TM/LP for a reactor trip, it is anticipated that the degradation in contain-ment trip setpoint accuracy would not be a signifi-icant factor. FSAR 14.17.2.4 states that the worst case ~for core effects) SBLOCA with a break area of

.1 ft , TM/LP gives the reactor trip at 15 seconds.

SIAS occurs at 20 seconds. Smaller breaks would result in later reactor trip times while containment conditions are degrading. The small break size, however, also makes containment heat removal equip-ment (containment spray and containment air coolers) become more effective at removing the LOCA energy released to containment and therefore make the re-sulting containment environment less harsh. In addition, instrument.responses become less critical because the severity of the core effects from the SBLOCA are much less as break size decreases.

MI0290-008A-TC07 Page 6 of 7

-* ,. ~ ~-

Actuation of the PORV's is disabled during normal plant operations. Enabling of the PORV is a manual function performed by the operator later in the accident if required. The safety analysis does not take credit for automatic actuation of the PORV's for high pressure protection. Therefore, the input to the PORV actuation logic is not required. Based on this discussion the functions provided by these transmitters will still be achieved.

FE/FM 1039, FE/FM 1040, PRESSURIZER RELIEF VALVE POSITION INDICATION FE/FM 1041, FE/FM 1042B AND FE/FM 1043B These instruments provide relief valve pos1t1on indication by detecting flow thru piping downstream of the pressurizer relief valves and activating an alarm in the control room. FE/FM-1042B and FE/FM-1043B have redundant indication provided by the position switches which are integral with the power operated relief valves PRV-1042B and PRV-1043B.

FE/FM-1039, FE/FM-1040 and FE/FM-1041 are on the downstream side of the code safety relief valves.

The only accidents in which these valves are postu-lated to open are a loss of feedwater event or a loss of external load event. The containment environment does not become harsh in these events and therefore the connectors associated with these instruments will not degrade during the event. Based on the discus-sion above, the functions provided by these instru-ments will still be achieved.

CONCLUSION: The possible erractic readings of the above instruments resulting in their inability to perform their function during a portion of a LOCA or MSLB will not result in an unsafe condition.

MI0290-008A-TC07 Page 7 of 7

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