ML17249A970
| ML17249A970 | |
| Person / Time | |
|---|---|
| Issue date: | 09/12/1977 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE) |
| To: | |
| References | |
| IEB-77-03, IEB-77-3, NUDOCS 7912130844 | |
| Download: ML17249A970 (10) | |
Text
NUCLEAR REGULATORY COHMISSION OFFICE OF INSPECTION AND ENFORCEMENT MASHINGTON, D. C.
20555 IE Bulletin 77-03 Date: September 12, 1977 ON-LINE TESTING OF THE MESTINGHOVSE M SOLID STATE PROTECTION SYSTEM (SSPS)
Description of Circumstances:
Mestinghouse has recently reported that operation of the safeguards actuation block/reset circuitry is not being verified during the peri-odic semi-automatic logic testing of the Solid State Protection System as required by licensee's technical specifications.
Even though this portion of the logic system is tested prior to initial plant operation, circuit failure-during operation is un(etectable.
Consequently, if any part of this circuitiy fails, safety injection could not normally be reset and/or blocked.
Resetting and blocking of safety injection signals are necessary for switchover to the recirculation mode of operation during accident conditions.
The enclosed M Technical Bulletin NSD TB-77-11 was sent to affected Mestinghouse plants notifying them of the probl.em and of the corrective action necessary to resolve the issue.
The technical bulletin provides detailed information to augment estab-lished on-line test procedures.
The method has been confirmed recently by successful verification tests of the WSSPS at both M Nuclear Instru-mentation and Control Division (MNICD), Hunt Valley, maryland, and North Anna Nuclear Station.
I Action To Be Taken By Licensees and Permit Holders:
For all M Power Reactor Facilities with an operating license or a con-structlon perml t:
l.
If your facility utilizes or plans to utilize the MSSPS, describe what action you have taken or plan to take to assure adequate periodic testing of all portions of the system.
Further informa-'ion regarding the necessary periodic testing procedures can be obtained from Mestinghouse Nuclear Energy Systems in Monroeville, Pa.
IE Bul'letin ?7-03 Date: September 12, 1977 2.
Report to this office in writing within 45 days for facilities with an operating license and within 60 days for faci'lities with a construction permit, your plan of action with regard to Item 1.
Approval of NRC requirements for reports concerning possible generic problems has been obtained from the U: S. General Accounting Office.
(GAO approval B-180225 (R0072, expires 7/31/80).
Enclosures:
l.
Extract from M Technical Bulletin NSD TB 77-11 Entitled:
Periodic Testing of Safety Injection Reset Timing Circuit 2.
List of IE Bulletins Issued in 1977
(
~
(
~
Subject:
Number:
System(s):
Date:
COPY (Extracted From W Technician Bulletin NSD TB 77-11)
PERIODIC-TESTING OF SAFETY INJECTION RESET TIMING CIRCUIT NSD-TB-77-11 Solid State Protection System (SSPS)
July 21, 1977 Affected Plants:
All with above supplied equipment S.
O. (s):
References:
385 SSPS Schematic, Sheet 20 BACKGROUND INFORtQTION A portion of the safeguards actuation reset circuitry which would not normally be tested during periodic on-line testing of the Solid State Protection System has been re-evaluated and does now require periodic test.
The specific circuit consists of timing relay TDl, slave relay K602, control board SI block/reset pushbutton and associated wiring including wit ing back to universal card A216-19 beyond which is included in the sems-automatic logic tests.
Should any part of this circuit fail, safety injection could not normally be reset and/or blocked to allow initiation of recirculation.
Mestinghouse has concluded that this constitutes a potential substantial safety hazard and has notified the U.S.
NRC in accordance with reporting requirements.
IMMEDIATE CORRECTIVE ACTION The following scheme is to be employed during periodic on-line testing of the Solid State Protection System:
1.
Place "Input Error Inhibit" switch on logic test panel to "In-hibit."
Z.
Place the "Mode Selector" switch in output cabinet to "Test."
3.
Select position 9 on "Memories" switch on the logic test panel
- and, if the "Memory Set" light is on, depress the adjacent black push button to extinguish.
COPY Enclosure 1
Page 1 of 3
COPY 4.
If K602 actuates any external loads, first block these loads from the external test circuitry.
Do not attempt to energize K502 from this circuitry.
6.
Connect a DC,voltmeter (Simpson Model 26). between time delay relay (TD1) terminal 6 (+) and logic ground (GND) on the logic test panel using the 50 volt scale.
The meter should read 48VDC (nominal).
Move the positive (+) probe from TD1-6 to TDl-2.
The meter should read 0 VDC.
7.
Latch-up K602 by physically depressing the latch plunger and releasing.
Time the interval beginning with that action until the volt meter reads 48 VDC (nominal).
This period should agree with that specified on the applicable technical specification.
8.
From the main control board, firmly depress and release the SI block/reset pushbutton and the following will occur simultaneously:
a.
The Memory Set" lamp will light.
I b.
The voltmeter will go to zero.
c.
K602 will reset as evidenced by the protruding latch plunger.
At this point, the operation of K602 and latch, the operation of TD] coil and contacts, the application of an SI block (memory set light), the operation of the control board reset switch and all associated wiring has been checked and verified.
9.
Return the "Memories" switch to "Off" position.
10.
Return the "Mode Selector" switch to "Operate."
ll.
IMPORTANT:
Since use of the "Memories" switch could have negated valid blocks which existed before its use, reinstate all blocks from the control board by actuating ALL manual block pushbuttons.
12.
After performing step 11, return "Input Error Inhibit switch to "Normal."
COPY Enclosure 4
Page 2 of 3
COPY In order to verify that all contacts returned to
- ditions, do the following:
13.
Connect the voltmeter between TD1-6 (+) and The meter should read 48 VDC (nominal).
14.
Switch to ohms Rxl range and measure for an TD1-2 and logic ground (Gl'ID).
their initial con-logic ground (GND).
open circuit between 15.
Connect the meter to read volts AC (150 VAC Range) across TD1-1 and 5.
The meter should read 0 VAC.
16.
Switch to Rxl range and measure for an open circuit between TD1-1 and 5.
- 17. If applicable, return the slave relay K602 external testing circuit to its nonblocking state thus restoring the entire system to full service.
The circuit has now been verified as being in its initial state after having performed.
COPY Enclosure 4
Page 3 cf 3
IE Bulletin 77-03 LISTING OF IE BULLETINS ISSUED IN 1977 Bulletin No.
77-01 Subject Pneumatic Time Delay Set Point Drift First Date Issued 4-29-77 Issued To All Holders of Operating License (OL) or Construc-tion Permit (CP) 77-02 Potential Failure Mechanism in Certain ll AR Relays with Relays with Latch Attachments 9-12-77 All Holders of Operating License (OL) or Cons'truc-tion Permit (CP)
Enclosure 2
Page 1 of 1
, I' I!IVX/j,'/I74;W/I
',',I//,
A A D ROCHESTER GAS AND ELECTRIC CORPORATION
~ *
~ <<
< ~
~
89 EAST'AVENUE, ROCHESTER, H.Y. 14649 LEON D. WHITE< JR.
VICE PRCSIOCNZ T E'ER<IONC AREA COOC 7IE 546.2700 June 8, 1977 Mr. James P. O'Reilly, Director U. S. Nuclear Regulatory Commission Office of Inspection apd Enforcement
.Region I 631 Park Avenue King of Prussia, Pennsylvania 19406 Subject.
IE Circular 76-06:
Stress Corrosion Cracks in Stagnant, Low Pressure Stainless Piping Containing Boric Acid Solution at PWR's R. E. Ginna Nuclear Power Plant, Unit gl Docket No. 50-244
Dear Mr. O'Reilly:
In our December 21, 1976 letter in response to IE Circular No.
76-06 we stated that certain actions would be taken during the'1977
, refueling and maintenance outage to verify the integrity of the containment spray and safety injection systems.
The LER 76-24/10 update report
. transmitted today within a separate letter provides the results of the completed actions.
Very truly yours, xc:
NRC Office of Inspection and Enforcement Division of Reactor Inspection Programs Washington, D. C.
20555
ROCHESTER GAS AND t
et ~
a a
~ ~
~
~ e Wait ELECTRIC CORPORATION
~
89 EAST AVENUE, ROCHESTER, N.Y. 14649 L.EON D. WHITL,JR.
VICC PRCSIDEIrT May 31, 1977
'laI.CRIIONC anna coIIc Tin 546-2700 Mr. James P. O'Reilly, Director U. S. Nuclear Regulatory Commission Office,of Inspection and Enforcement Region 1
631 Park Avenue King of Pr'ussia, Pennsylvania 19406
Subject:
IE Bulletin No. 77-01:
Pneumatic Time Delay Relay Setpoint Drift R. E. Gian~a cleIIr Po'wer Plant, Unit $ 1 Docket No 0-244
Dear Mr. O'Reilly:
This letter is in response to Inspection and Enforcement Bulletin 77-01, dated April 29, 1977, and received at Ginna Station on May 2, 1977 concerning a number of malfunctions of pneumatic time delay relays at the Millstone and North Anna facilities.
No time delay relays of the type iden-tified in the subject Bulletin are used at Ginna Station.
To date none of the Agastat time delay relays used throughout Ginna Station have caused any unwanted equipment response..
The manufacturer's specifications for these devices state that for units set at 200 seconds gr under, repeat accuracy is better than + 5% of pre-set adjustment.
Timing verification checks of Agastat relays, where used to perform critical operations in safety related systems, are performed at each refueling outage.
The systems in which relay timing is verified include the A & B Diesel Generators and the A 6 B Safeguard train equipment sequencing operation.
Other time delay. relays are in service to which safety connotation may be attributed; these relays, while not checked for
'specific time response, are proven to be functionally adequate as witnessed by correct, overall system operation which is dependent upon the time delay units.
A review of all Agastat time delay relays which are presently not being "time checked" willbe conducted, and if warranted willbe added to the surveillance program for subsequent refueling outages.
Very truly yours, L. D. White, Jr.
xc:
NRC Office of Inspection and Enforcement-1'Division of Reactor In'spection Programs Washington, D. C.
20555