ML20151N592
| ML20151N592 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 12/20/1985 |
| From: | Carey J DUQUESNE LIGHT CO. |
| To: | Knighton G Office of Nuclear Reactor Regulation |
| References | |
| 2NRC-5-151, NUDOCS 8601030020 | |
| Download: ML20151N592 (5) | |
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'Af Duquesne Lidit g;ggAP Nuclear Construction Division hlecon Ne u* g"[P $5 5 necember 20, 198s I
United States Nuclear Regulatory Commission Washington, DC 20555 ATTENTION:
Mr. George W. Knighton, Chief Licensing Branch 3 Office of Nuclear Reactor Regulation
SUBJECT:
Beaver Valley Power Station - Unit No. 2 Docket No. 50-412 Safety Paraneter Display Systen (SPDS) -- Request for Additional Information Gentlenen:
The staff has requested additional infonnation in order to conplete the review of the SPDS safety analysis and implenentation plan. The infonna-tion requested by the staff and responses provided by Duquesne Light are attached.
Please note that the responses to the questions on Isolation Devices are organized to point to specific references which contain the answers.
These referenced documents are auditable by NRC reviewers (EQ docu-mentation packages and QA Category I specifications) or are in NRC possession (WCAP s).
DUQUESNE LIGHT COMPANY By
(
J'. J. Carey Vice President MED/wj s
.it t achnent cc:
Mr. B. K. Singh, Project Manager (w/a)
Mr. G. Walton, NRC Resident Inspector (w/a) 8601030020 851220 PDR ADOCK 05000412 F
PDR gg AD - J. kNIGtT (ltr only)
EC8 A)
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FOB (BENAROYA)
ATTACHMENT o
Additional Information Safety Paraneter Display Systen Instrunentation and Control Systems Information Question 420.01: " Isolation Devices" a.
For each type of device used to acconplish electrical isolation, describe the specific testing perfonned to denonstrate that the device is acceptable for its application (s). This description should include elenentary diagrans when necessary to indicate the test configuration and how the maximun credible f aults were applied to the devices.
Response.
Specific testing perfonned for each isolation device is described in the EQ documentation package for the purchase order.
Three purchase orders.are involved.
The testing description is listed below:
P.O.
Test Infonnation Applicable Model No.
2BV-001 WCAP-8892A 2837 A 12 G02 2837 A 12 G03 l
2BV-723 WCAP-8892A 2837 A 12 G02 2837 A 12 G03 1
,CX 3916 NE package and 2BVS-739 CX 3918 NE b.
Data to verify that the maximun credible faults applied during the test were the maximun voltage / current to which the device could be exposed, and define how the maximun voltage / current was determined.
p I
Response
l Each test report describes the testing configurations used, paran-eters selected, and how the maximun voltage / current was detennined.
I L
BVPS-2 satisfies the assunptions of WCAP-8892A for analog signal isolation. For digital signal isolators (2BV-739), maximum voltages i
l were determined by assuning a single f ailure at a 480V systen or Cdble plus 10% margin or a conparable DC f ailure with a 13.6%
margin.
c.
Data to verify that the maximum credible fault was applied to the output of the device in the transverse mode (between signal and i
return) and other faults were consioered (i.e.,
open and short I
circuits).
l
Response
Refer to each test report for the test configuration.
i l
L_
d.
Define the pass / fail acceptance criteria for each type of device.
Response
Refer to each test report for pass / fail criteria.
e.
A conmitment that the isolation devices conply with the environnental qualifications (10CFR50.49) and with the seisnic qualifications which were the basis for plant licensing.
Response
The isolation devices do conply with the environnental and seisnic qualifications which were the basis for plant licensing.
Refer to each EQ docuinentation package for data substantiating this comnitment.
f.
A description of the measures taken to protect the safety systens fron electrical interference (i.e.,
Electrostatic Coupl ing, EMI, Conmon Mode, and Crosstalk) that may be generated by the SPDS.
Response
The Emergency Response Facility Conputer Systen (ERFCS), in which the SPDS software resides, is installed wi thin the Emergency Response Facility; a building located approximately 1500 feet fron the pl ant.
Distance is expected to minimize the potential for interference.
Inputs in the plant are installed in accordance with the manuf acturer's (Bailey Controls Co.) installation manual which contains stringent guidelines for minimizing noise pick-up, cross-talk, signal distortion, and attenuation.
Human Factors Engineering Information Question 620.01:
" Data Validation" Describe the specific methods used to validate data displayed in the SPDS. Also describe how invalid data is defined to the operator.
Response
The Redundant Sensor Algoritha (RSA) processes redundant sensor inputs and (when possible) returns a group value of the valid sensor for the use in upper level di spl ays.
Valid signals are selected by first eliminating those values which result fran known bad input points (either by autonatic hardware checking or by operator input), those values which are not periodically updated (renoved fron scan), and those values which have previously failed the sensor consistency check.
The renaining signals are then exanined for consistency within a predetennined tolerance.
If no more than one of these signals f ails to agree within the tolerance, the average value of those signals within the tolerance will be
given a quality code of POOR and will not be considered in subse-quent evaluation cycles until the value returns within the accept-able tolerance.
In the case where only a single sensor value is presented to the consistency checking routine, that sensor value will be used for the group value.
If no sensors reach the consis-tency check, or if more than one of the signals reaching that check do not pass the test, then no value is assigned to the group value and the group value will be given a data quality of BAD.
The following quality codes will be used for individual sensor values:
Quality Code Description BAD 3
. Signal missing or renoved fron sc an with no value entered, or fron an I/O point which was detected as f ailed by 4
i systen diagnostic routines.
P00R 2
A signal which has f ailed the group consistency checking.
MANUAL 1
Signal has been renoved fran scan and a value has been manually entered.
GOOD 0
A sensor value that is not BAD, P00R, or MANUAL.
For redundant sensor, the following group quality codes will apply:
Quality Code Description BAD 3
No GOOD quality sensor inputs for the group are found in th~e signal consis-tency checking.
P00R 2
Group quality is not BAD, but one or more of the individual group sensors has a quality other than GOOD.
MANUAL 1
Not applicable; a manually entered group value will not be utilized, 4
i GOOD 0
A group value which is neither BAD nor POOR.
Manual and Poor data Data quality representation to the operator: -for manual and a "P" quality are represented by appending an "M"
for poor to the variable and a change in color code.
Bad data i
quality 'is represented by appending a "B" to the variable and a change in color code.
For alphanumerics of Bad quality, "XXXX" is substitued for the value.
Good data quality is represented by the absence of either Bad, Poor, or Manual data quality, i
...y_.,
Question 620.02:
" Verification and Validation Program" Define and discuss the Verification and Validation Progran Plan which was used in the developnent of the SPDS.
Also describe results to date fran the Verification and Validation Progran and the corrective actions taken to address identified design deficiencies.
Response
WCAP 10170, Appendix E, describes the V&V progran used during SPDS development.
This document is in the NRC's possession and has been reviewed.
DLC has purchased an SPDS with no uncorrectec design deficiencies.
Note that the SPDS has not yet been installed so V&V of the integrated systen have not yet been perfonned.
Question 620.03:
"Unreviewed Safety Questions" Provide conclusions regarding unreviewed safety questions or changes to technical specifications.
Response
This question does not apply since no SER has been issued.
Question 620.04:
" Implementation Plan" Provide a current schedule for full implenentation of the SPDS including hardware, sof tware, operator training, procedures, and user manual s.
Response
Hardware, software, and draft instruction manual delivery are currently schedul ed for February 3.
1986.
Bailey Controls Co.
intends to deliver the final operator's manual within three months of shipnent after conments are resolved. The SPDS will be available for operator training by Novenber 30, 1986, and operational three months prior to fuel load. Operator training will be conpleted one month prior to fuel l oad.
Initially, the E0Ps will be developed without the operation of the SPDS.
When the SPDS sof tware manuals becone available, they will be reviewed for possible incorporation into the E0Ps.