05000302/LER-1981-035-03, /03L-0:on 810616,regulating Rod Groups 6 & 7 Exceeded Overlap Requirements.Caused by Procedural Deficiencies Resulting in Failure to Note Loss of Permissive Logic When Transferring Power Supplies

From kanterella
Revision as of 08:31, 21 December 2024 by StriderTol (talk | contribs) (StriderTol Bot insert)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to navigation Jump to search
/03L-0:on 810616,regulating Rod Groups 6 & 7 Exceeded Overlap Requirements.Caused by Procedural Deficiencies Resulting in Failure to Note Loss of Permissive Logic When Transferring Power Supplies
ML20009E678
Person / Time
Site: Crystal River 
Issue date: 07/14/1981
From: Hernandez V
FLORIDA POWER CORP.
To:
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML20009E672 List:
References
LER-81-035-03L, LER-81-35-3L, NUDOCS 8107280357
Download: ML20009E678 (2)


LER-1981-035, /03L-0:on 810616,regulating Rod Groups 6 & 7 Exceeded Overlap Requirements.Caused by Procedural Deficiencies Resulting in Failure to Note Loss of Permissive Logic When Transferring Power Supplies
Event date:
Report date:
3021981035R03 - NRC Website

text

... =.. :.=.:. :., : =..:.: a

v._ p.. \\..

.r e

e s

e g

.-e.y..

p

...,,c.

..., :u: %. --...,2.,.,,

, y _.,;.,,.,,,,

.. m.,...

.,i :.:

-=

,; m,'...,, h j, 1.

.3

. =.. i e a:2

_:.....m a

,m :: -

2:

.o.6'1'6 8*1.?071 4 :8 1

_.7._. :

I:

= i.: e.

..23 a

4, y.:.r :. t u _.

r. s. : : :=.. :. ::. : r.:t -: : ::.:::.r. : : c:.

At 1525 following performance of PM-Y26, Electrical Checks of CRD Powe. Train, Regula -

ting Rod Groups 6, & 7 exceeded the rod group-overlap requirement'of T.S. 3.1.3.6.

The;

. overlap condition was corrected at 1535 by manually adjusting group 7 position. There

, was no effect upon the health or safety.of the general public. This was the first oc.

,3,

.,, ; currence of this type and this is the third event reported under'this Specification.

:.. t i: ii i

r s tu u::

a.

,,,, ~

s
s r. : =
...:ste :::t r.n::

ra = s 1: 154

! RI B I h I._D_I h ! ZI h l_ZI Z I ZIZIZl.,Z_jh IZlh !Zi@

t a

e ic n

i:

s

=

!! :'.1 %."% c.

  • a6
rge21%:*

a g e:m; a g. ;;. 0 %

te n.c E'.' t % ?. t. m u t. 2

g

,,g

,, g 6.".y, t._ aI 81 li t-I I O f 31 S I I/l 10I3i ILl QJ

=

=

4
s
s

=

,_:,: ~ ;..

i. :-

..., s r

s.u s-c, :-,

_. >. -.u. 1

... = _,.

_ :.,:.a,.

v u-

.: :- =

o r.....

! x'g! al@

i Zig i Zi@

t 01 01 Or i

(Yig

lNlg, [Zj$

l Zi 9!9 1 9 l(

=

=

w c.wsz ::s:x;i.c.4 u.:::a =::nvs 2 - :.es g ei. The cause of this event is attributed to/ procedural deficiencias resulting in fal. lure tia:

L.-

ii, i; ! to recognize loss of permissive logic /(group S out-limit) af ter transferring control i

. t power from auxiliary to normal supply. Group 5 was adjusted to restore the out-limit.

(,i: i I for normal sequencing of group 7.

Applicable proemiures will be revised to note the I i

.4 i i potential for loss of cermissive logic when transferring power supplies.

I 2

c 2,

c.s s.
e. : 2-.s (j
.ir.:: :.

Q::

. ic:: -

a-t::.a.

. 3...... a p.,.,

. I E.h 3_,+

1. 0 I 8 I 3 _l 9 !

NA I

I B I!9:!. Operator observation i

i: i s

m.,

i..

i:

u -. ::e:w a

g

_2t'j:l 1 *:j,

.. 7. %-* 2 8 a: :V "Y * :;,1

( <;;;.:s :s ar.;a. g d e

_8 8 7 '.!

8 ?.! M *:

NA 8

I NA i

!i.

t i,

,.::~ss t r :-ac

=..- :,f.n s..in.

.' 01 Oi 0 @v.

Z'9,_.9 NA n s ::. *. -._. a x t:

p

... m.- -s u :

ciri 1 0,,* 01 O! g [- - * -
  • v NA i

ie n

e.

3

.::: :. := :im;r : ne:.,c

--t

suw ic I i i = i ! Z!(dl NA v

a >

3

~.r > : ~

Q

. @;:e: --.:s c t

N NA 7:ees 1 j

7.i

,,t

..are or Preparer:

c a i i;.

( c. r. L) 7 0..= :. ' :. :

,.cy g.

O ': Z'.~';TA.T C-"NI 7.hC ;.~5.'I.: I}

8107280357 810714 PDR ADOCK 05000302 II

.Cl S

PDR

ll e

s f

SUPPLEMENTARY INFORMATION Report No.:

50-302/81-035/03L-0 Facility:

Crystal River Unit 3 Report Date:

July 14,1981 Occurrence Date:

June 16, 1981 Identification of Occurrence:

Regulating rod groups 6 & 7 exceeded the rod group cverlap requirement of Technical Specification 3.1.3.6.

Conditions Prior to Occurrence:

Mode 1 power operation (83%).

Description of Occurrence:

At 1525 following performance of PM-126 Electrical Checks of CRD Power Train, regulating rod group 7 failed to respond to the sequence auto signal. This resulted in group 6 being withdrawn to 100% while group.7 remained withdrawn at 15%.

Group 7 positi n was manually adjusted and compliance to the Technical Sp'.ification was achieved at 1535.

Designation of Apparent Cause:

The cause of this event is attributed to prccedural deficien-cies resulting in failure to recognize the loss of group out-limit for group 5 rods which disabled the permissive logic for sequencing group 7.

The loss of out-limit occurred after transferring control power from auxiliary to normal supply at the completion of PM-126.

Analysis of Occurrence:

There was no effect upon the health or safety of the general public'.

Corrective Action

Rod group 5 position was adjusted to restore the out-limit for normal sequencing of group 7.

Applicable procedures will be-revised to note the potential for disabling the permissive logic when transferring power' supplies.

Failure Data:

7 This was the first occurrence of this type and this is the third event reported under this Specification.

/rc