ML20039B704

From kanterella
Jump to navigation Jump to search
RO 81-56:on 811215,during Testing of Reactor Protection Sys Channel B,Channel C Was in Manual Bypass and Not Tripped Per Tech Spec.Min Level of Redundancy Not Maintained.Further Rept in 14 Days
ML20039B704
Person / Time
Site: Rancho Seco
Issue date: 12/16/1981
From: Reinaldo Rodriguez
SACRAMENTO MUNICIPAL UTILITY DISTRICT
To: Engelken R
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
References
RO-81-56, NUDOCS 8112230447
Download: ML20039B704 (1)


Text

__ _____

l d

S ACRAMENTO MUNICIPAL UTfLITY DISTRICT D 6201 S Street. Ow 15830. Sacramento California %Bil, Gl5) 4113211 RJR 81-695 Os.ccmbe r 16, 1927 D

gs R H ENGELKEN, ADMtMISTitATOR x

REGION V 0FFICE Or in5PECTION s. ENFORCEMENT

([,,,- C WE, _J g

'~

U S NUCLEAR REGULATORY COMMISSION 72 1

1450 MARI A LANE SulTE 710

%C 23N j

.w t -//

WALNUT CREEK CA 985a5 4

  • %EQ" * }

/N I l t[

DOCKET NO. 50-312 d

LICEMSE NO DPR-54 REPORTABLE OCCURREtlCE Bi-56 In accordance wi th Pancho Seco Nuclear Generat ing St ation Technical Speci ficat ions Sec tion 6.9.4.1(f) and Regulatory Guide

1. t f. Sec t i on C.2.a(6), the Sacramento Munic i pa l Ut ility Oi t.t r i ct hereby submits the. following report of Reportable Occurrence 81-56.

Vhile performing instrument Survel11ance I-1088 with Reactor Protection System Channci C declared administratively inoperable and in Manual hypass, the inst ruraent Technician did not properly insure that the trip' system was properly set up to retain a minimum degree of redun-dancy as required by Technical SpecI fIcat ion sece ions 3.5.1 I and 3.5.1.2.

Procedure I-108B autfior' zed the testing of Channel B provided Channel C was tripped rather than bypassed.

With Channel C tripped the mi.nimum level of redutsdancy would have been retained during testing.

In fact, the technici an erroneous ly ~ used the sirnulat e trip switches

~

on the Reactor Trip Module in attempting to trip Channel C.

While this did open the breakers controlled by RPS Channel C as if it had tripped, it did not open the' relay contacts in t he two-ou t -o f-fou r relay. logic in the other RPS channels in order to change a two-out-of-three condition (established by placing RPS Channel B in Manual Bypass per 1-1088) to a one-out -of-two condi t ion, preserving the gainimum level of redundancy.

Thus as far as RPS Channel A and D were concerned, RPS Channel C was not t ripped.

This situation was discussed with the NRC Resident inspector on December f5. 1981.

A complete report wi t.) be forwar ded to your of fice within 14 days.

g p

R. J. Rod riguer

,/

ir rtanager Nuclear Operat ions

$ /

ll/O o!00$h2 D

PDR

/.. s t r c i r: : c s y s 7 : n s r t e r r.' c wor r inn

f. c o 0 4 9 in int stant us c r. i i s tr i: *< t A