ML19276F641

Final Rept,Ncr HNP-A-021,on Wiring Discrepancies in High Pressure Core Spray Diesel Generator Control Switchgear. Lists Discrepancies Found.Problems Have Been Identified & Will Be Corrected

ML19276F641
Person / Time
Site:	Hartsville
Issue date:	03/07/1979
From:	TENNESSEE VALLEY AUTHORITY
To:
Shared Package
ML19276F642	List: ML19276F641 ML19312A157
References
NUDOCS 7904060288
Download: ML19276F641 (7)

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. Hartsville Nuclear Plant, Units Al and A2 High Pressure Core Spray Diesel Generator Control Switchgear Wiring Discrepanciel Report No. 2 (Final)

NCR HNP-A-021 On August 10, 1978, TVA notified NRC-0IE Region II Inspector, John Rausch, of a potentially reportable condition regarding wiring discrepancies that had been discovered in the unit Al and A2 high pressure core spray (HPCS) diesel generator (DG) control switchgear.

TVA issued the first interim report to the NRC concerning this NCR on September 8, 1978. This is the final report on this NCR. This NCR now also applies to units B1/B2 for Hartsville and Phipps Rend units 1 and 2.

w Description of Deficiency During the course of attempting to energize the panel space heaters internal to the unit Al and A2 HPCS DG control switchgear, s,everal wiring discrepancies between the latest revision drawings from TVA's document control center and the "as-built" panel were discovered. Discovery of these initial wiring discrepancies resulted in both the unit Al and A2 HPCS DG control switchgear being given a complete wire check against the latest revision of the drawings in TVA's possession. This wire check resulted in the wiring discrepancies listed below. (Those. discrepancies deemed significant are prec,eded by an "*.")

LIST OF DISCREPANCIES FROM ORIGINAL REPORT Unit Al I. Voltage Regulator and Exciter Cubicle

• A. Wire Nos. 249 and 250 of the exciter ammeter (detail 37A) D. C.

terminals are reversed from what is shown on WD-100-6005, sheet No . 6.

B. On WD-100-6005, sheet No. 6, the " auto-manual" (dt til 40) switch has the ;ollowing discrepancies:

1. Terminal No. I of the " auto-manual" (detail 40) has two wires labeled M-28. The wiring diagram shows these wires labeled as M-26.

• 2. Wire No. 254 is on terminal Ma. 9, but the wiring diagram shows wire No. 254 on terminal No. 3.

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C. The " emergency voltage shutdown" switch (detail 39) of WD-100-6005, sheet No. 6, has on one terminal two wires labeled M-28, but the wiring diagram (WD-100-6005, sheet No. 6) shows these wires labeled as M-26.

• D. Terminals 19 and 21 of TBC do not have the jumper between them which the wiring diagram (WD-100-6005, sheet No. 7) shows clearly.

E. TBC has a wire labeled 220 attached to terminal No. 52; the wiring diagram (WD-100-6005, sheet No. 7) shows a wire labeled G20 attached to terminal No. 52.

F. TBS was not labeled.

II. Engine Cratrol Cubicle

• A. Wire Nos. 87 and 88 of the unit mode red and green pilot lights are reversed as to what is shown on sheet No. 1 of WD-100-6005-RA.

B. TB1 was not labeled.

C. FFP1 was not labeled.

D. On TB3, AC-1, AC-2, AC-3, and AC-4 are not identified on sheet No. 3 of WD-100-6005-RO. These terminais oppear to

., . be terminal Nos. 93, 94, 95, and 96.

III. Metering Cubicle

• A. Wire Nos. 217 and 218 en the circuit breaker (HPCS Buss, detail 16) are reversed as to what is shown on sheet No. 4 of WD-100-6005-RA.

• B. Wire Nos. 227 and 228 on the circuit breaker (normal supply, detail 12) are reversed as to what is shown on sheet No. 4 of WD-100-6005-RA.

C. Wire No. 241 of the ground detection relay (detail 29 of WD-100-6005, sheet No. 5) is not labeled.

• D. " MOP VR" (detail 36 of WD-100-6005, sheet No. 5) has two wires labeled 206 connected to its terminal No. 6. The wiring diagram shows two wires labeled 206 at terminal No. 6.

• E. " MOP GOV" (detail 35 of WD-100-6005, sheet No. 5) has one wire labeled 206 connected to its terminal No. 6. The wiring diagram shows two wires labeled 206 at terminal No. 6.

IV. Transformer - Reactor Cubicle Rear door to the cubicle will not open without considerable force. Rough welding on rear door hinge was neither sanded nor painted.

Unit A2 I. Voltage Regulator and Exciter Cubicle A. A discrepancy exists between sheet No. 5 of WD-100 6005-R0 and schematic No. 6005F11501-RC. Fuses FU6P, FU6N, FU7P, and FU7N are wired as shown on sheet No. 5 of WD-100-6005-RO, but the following changes need to be made to schematic No. 6005F11501-RC ior agreement with sheet No. 5 of WD-100-6005-RO:

1. FU6P to read FU6N

2. FU6N to read FU6P

3. FU7P to read FU7N

4. FU7N to read FU7P

• B. The termination of the following wires on each detail listed is reversed from what is shown on sheet No. 6 of WD-100-6005-RB:

., 1. Wire Nos. 229 and 230 on the DC ammeter (DC supplys (detail 44).

2.

Wire Nos. 249 and 250 on the exciter ammeter (Detail 37A)

DC terminals.

3.

Wire Nos. 251 and 252 on the " auto-man" (detail 40) pilot lights.

• C. A discrepancy exists between sheet No. 6 of schematic No. 6005F02501 and sheet No. 7 of WD-100-6005-RA. The .

schematic shows space heater terminals as AC-17 and AC-18 on TBC. The space heaters are terminated at TBC AC-19 and AC-20 as shown on WD-100-6005-RA, sheet No. 7.

• D. Loose crimp on No. 2 SCR red lead.

• E. A screw is wedged between the door and circuit breaker for DC distribution.

II. Engine Control Cubicle

• A. Wire No. 52 on terminal No. 3 of relay R7X is not shown ou sheet No. 2 of WD-100-6005-RA. This wire (No. 52) goes to TD8 (L1).

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• B. Terminal No. 3 of relay SSI does not have wire No. 52 as shown on sheet No. 2 of WD-100-6005-RA.

• C. Terminal No. 6 of relay SDRXI has two wires labeled FC plus a jumper to terminal No. 6 of TD5X. Sheet No. 2 of WD-100-6005-RA does not show any wires or jumper on terminal No. 6 of relay SDRXI.

• D. Wire No. 61 on terminal No. 56 on the mode selector switch of sheet N'o . I of WD-100-6005-RA has no terminal lug and the screw is missing from the terminal. This wire has not been terminated.

• E. Wire Nos. 87 and 88 of the unit mode red and green pilot lights are reversed as to what is shown on sheet No. 1 of WD-100-6005-RA.

• F. Wire Nos. 151 and 152 of the " auto-man" switch of the air compressor are reversed as to what is shown on sheet No. 1 of WD-100-6005-RA. This reverses the manual-auto functions of the selector switch.

• G. Wire Nos. 164 and 165 of the immersion heater selector suitch are reversed as to what is shown on sheet No. I of WD-100-6005-RA. This reverses the manual-auto functions of the selector switch.

- H.

On TB3, AC-1, AC-2, AC-3, and AC-4 are not identified on sheet No. 3 of WD-100-6005-R0. These terminals appear to be terminal Nos. 93, 94, 95, and 96.

• I. Sheet No. 2 of WD-100-6005-RA shows wire No. 98 on terminal No. 9 of relay R2 looping back on itself. This terminal should be referenced to relay FR terminal No. 3.

III. Metering Cubicle

• A. Wire Nos. 217 and 218 on the D. C. circuit breaker (HPCS Buss, detail 16) are reversed as to what is shown on sheet No. 4 of WD-100-6005-RA.

kB. Wire Nos. 227 and 228 on the D. C. circuit breaker (normal supply, detail 12) are reversed as to what is shown on sheet No. 4 of WD-100.-6005-RA.

C. TB4 has only 72 terminals. Sheet No. 5 of WD-100-6005-RA thows Nos. 72 through 84 as spares.

• D. On TB4, terminal No. 36 wire No. 203 is loose.

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IV. C. T. and P. T. Cubicle A. A discrepancy exists between sheet No. 8 of WD-100-6005-R4 and schematic 6005F11001-RA, sheet No. 1. To resolve this discrepancy, the following changes need to be made to the wiring diagram and the schematic.

1. On 6005F1101, sheet No. 1, change T3 to T2 and T2 to T3 (drawing coordinates G&DE) .

2. On WD-100-6005-R4, sheet No. 8 for PT's:

• a. Eliminate drawing jumper from PT1(H1) to PT3(H1).

• b. Eliminate drawing jumper from PT2(H2) to PT4(H2).

c. Change wire No. T1 to read T3 off PTI(H1).

d. Change wire No. T2 to read T1 off PT2(H2).

e. Change wire Nos. T3 to read T2.

f. Change wire Nos. T2 to read T3 off of PT4(H2).

These changes dill resolve the discrepancies between the drawings (schematic and wiring diagram) and the actual wiring.

A subsequent repeat of the wire check of these switchgear by both GE site and TVA Construction personnel revealed the following corrections and additions to the above listing of wiring descrepancies.

CORRECTION S , ADDITIONS, AND DELETION TO DISCREPANCIES FOR FINAL REPORT Unit Al

1. Discrepancies noted in items I.E, I.F, II.B, II.C, III.C, III.D, and III.E in the original listing above were found not to exist.

2. The wording in item II.A should be replaced with the following:

" Wires No. 87 and 88 of the unit mode red and green pilot lights are labeled backwards from what is shown on Sheet 1 of drawing number WD-100-6005-RA."

3. Add the following under item I.B above.

"*3. Wire No. 5 is on terminal No. 9, but the wi, ring diagram shows wire No. 5 on terminal No. f.

"*4. Wires No. 251 and 252 on the " auto-manual" pilot lights are reversed from what is shown on the wiring diagram."

4. In item I.B.2 above " terminal No. 9" should be " terminal No. 6."

Unit A2

1. Items I.D, I.E, II.C, and IV.A.2 in the original listing above were found not to exist.

2. In item II.C " terminal No. 6" should be " terminal No. SC."

The corrections to the original listing of the "as-found" wiring discrepancies resulted because TVA Construction personnel had not been supplied the latest "as-built" drawings by GE and their subcontractor Morrison-Knudson. The fact that TVA did not have the latest revision of the wiring diagrams to perform the wire checks was discovered when GE site personnel were notified of this nonconformance.

These control switchgear were procured by TVA as part of the NSSS package supplied by General Electric (GE) and were fabricated by the Morrison-Knudson Company under a subcontract with GE.

The discrepancies noted above for units Al and A2 were determined reportable because, if the discrepancies remained uncorrected, one or more of the discrepancies could lead to the impairment of the ability of the HPCS DG and ultimately the HPCS to perform its intended safety function.

Before a wire check of the unit B1 and B2 swicchgear could be performed GE decided that the problem was generic with all the TVA HPCS DG switchgear.

Subsequently, GE decided to ship the Hartsville A1, A2, B1, and B2 and the Phipps Bend unit I and unit 2 switchgear back to Morrison-Knudson to

.be reworked to match the wiring and connection diagrams. Therefore, no details on the magnitude and types of wiring discrepancies in the Hartsville B1 and B2 and the Phipps Bend unit 1 and 2 switchgear are available.

Cause of Deficiency GE has determined that this nonconformance is indicative of a quality assurance / quality control (QA/QC) problem within Morrison-Knudson.

Documentation in the Morrison-Knudson shop indicates that the switchgear functioned properly in their shop before shipment to TVA. However, as this nonconformance shows many wiring discrepancies exist when the actual wiring is compared to the connection diagrams. This indicates that the certified "as-constructed" connection diagrams supplied with this switchgear were in error. As such, this condition represents a failure on the behalf of Morrison-Knudson to adequately document the final configuration of their product and to ensure that the final documentation package shipped with these switchgear was complete and accurate. This is the basis for the determination that a QA'QC problem exists at the Morrison-Knudson facility.

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GE has concluded that the reason the "as-constructed" connection diagrams do not reflect the actual switchgear wiring is two-fold. First, the switchgear were wired to the functional schematic diagrams rather than the connection diagrams. Second, the connection diagrams were prepared during and/or af ter the switchgear were fabricated; and the connection diagrams were neither checked against actual switchgear wiring nor prepared from the actual final switchgear wiring configuration. Coupled together these coglitions result in the situation documented in this NCR, i.e. switchgear that passed a functional test but did not have accurate documentation reflecting "as-built" conditions supplied with them to TVA.

TVA concurs with GE's determination of what caused this deficiency.

Safety Implications In view of this additional information the emphasis of this NCR shifts from the functionability of the HPCS DG switchgear as delivered to TVA to a QA/QC problem within the Morrison-Knudson shop wherein the connection diagrams were never "as constructed" to reflect the actual switchgear wiring configuration. Had this deficiency gone undetected, the potential existed for TVA to install the HPCS switchgear in the field utilizing the incorrect connection diagrams. This incorrect installation could impair the ability of the HPCS D6 and ultimately the HPCS to perform its intended safety function.

Corrective Actions The Phipps Bend (PBN) unit 2 HPCS DG switchgear and the PBN unit 1 HPCS DG are still at the Morrison-Knudson shop. The switchgear will be coupled to the DG, a complete performance test will be performed, and any detected wiring problems will be corrected. The switchgear wiring will then be reviewed, and the schematics and connections diagrams will be revised to reflect the wiring configuration of the "as-tested" switchgear.

The remaining HPCS DG switchgear (HTN A1, A2, B1, and B2 and PbN unit 1) have been shipped back to Morrison-Knudson; and as soon as the "as-tested" switchgear schematic and connection diagrams have been prepared and approved, each switchgear will be rewired as necessary, inspected, and shipped back to the respective TVA site.

Means Taken To Prevent Recurrence GL has informed Morrison-Knudson that the condition of the "as-constructed" drawings and HPCS DG switchgear is unacceptable to both GE and TVA and that GE expects Morrison-Knudson to correct this inhouse QA/QC problem with drawings. To ensure Morrison-Knudson executes these directives GE will increase their QA activity at the Morrison-Knudson facility.

In addition, TVA has informed GE that in the future "as-constructed" drawings must be shipped with any equipment that is received at the construction site.