United States Nuclear Regulatory Commission - Protecting People and the Environment

Information Notice No. 82-55: Seismic Qualification of Westinghouse AR Relay with Latch Attachments Used in System

                                                       SINNS, No.: 6835 
                                                       IN 82-55  

                               UNITED STATES 
                       NUCLEAR REGULATORY COMMISSION 
                    OFFICE OF INSPECTION AND ENFORCEMENT 
                          WASHINGTON, D. C. 20555 

                             December 28, 1982 

Information Notice No. 82-55:   SEISMIC QUALIFICATION OF WESTINGHOUSE AR 
                                   RELAY WITH LATCH ATTACHMENTS USED IN  
                                   WESTINGHOUSE SOLID STATE PROTECTION 
                                   SYSTEM 
                                   
Addressees: 

All holders of a nuclear power reactor operating license (OL) or 
construction permit (CP). 

Purpose: 

This Information Notice is provided as an early notification of a 
potentially significant problem pertaining to Westinghouse (W) AR relays 
fitted with type ARMLA latch devices which are not seismically qualified and 
may be used in safety-related systems at nuclear facilities. Specifically, 
the generic implications of the problem, as it applies to spare units, may 
affect both PWR and BWR operating plants and plants under construction. 

The Nuclear Regulatory Commission (NRC) staff is reviewing the problem and 
its effects. If the evaluation so indicates, NRC may request further 
licensee action. In the interim, we expect the recipients of this 
Information Notice to review the information herein for applicability to 
their facilities and to take appropriate actions. No specific action or 
response is required at this time. 

Description of Circumstances: 

Virginia Electric and Power Company (VEPCO) reported that one of the two 
types of latch mechanisms used with the Westinghouse type AR relay is not 
qualified for seismic Category 1 use. The licensee reports that both types 
of latch mechanisms are used in the Westinghouse solid state protection 
systems (SSPS) at both units of the North Anna Nuclear Power Station. 

One type of latch attachment, W ARLA performs the latch function by 
mechanical means; and the other type, W ARMLA performs the latch function by
magnetic means. The ARMLA relay is a product replacement for the 
discontinued ARLA relay. The type ARMLA relay, used as a replacement for the 
type ARLA relay unit, was found by W to be seismically unqualified for use 
in the safety-grade SSPS. 

On December 14, 1982, Westinghouse Nuclear Service Division (NSD) issued 
Revision 1 of Technical Bulletin No. NSD-TB-82-03 to Westinghouse-supplied 
nuclear plants using the SSPS, apprising them of the problem. An extract 
from W NSD-TB-82-03 is attached for your information and appropriate use 
(Attachment 1). 

8208190273 
.

                                                           IN 82-55 
                                                           December 28, 1982 
                                                           Page 2 of 2 

The technical bulletin specifies an acceptable replacement unit, qualified 
by Westinghouse, which has been provided with an adaptor base for mounting 
in place of an AR relay unit. 

It is well to note, that since the AR relay is not unique to Westinghouse 
PWR power plants, the problem may also exist at other nuclear power plants. 
Therefore, it is advisable for all nuclear power plants to review their 
replacement and spare parts records to ascertain that no W ARMLA units have 
been installed, or are being held as spare parts, safety-related 
applications. 

If you have any questions regarding these matters please contact the 
Regional Administrator of the appropriate NRC Regional Office or this 
office. 


                              Edward L. Jordan, Director  
                              Division of Engineering and  
                                Quality Assurance  
                              Office of Inspection and Enforcement 

Technical Contact:  V. D. Thomas 
                    301-492-4755 

Attachments:
1. Extract from Westinghouse Technical Bulletin NSD-TB-82-03, Rev. 1.
2. List of Recently Issued IE Information Notices 
.

                                                      Attachment 1  
                                                      IN 82-55  
                                                      December 28, 1982  

EXTRACT FROM WESTINGHOUSE TECHNICAL BULLETIN NSD-TB-82-03, "AR RELAY LATCH 
ATTACHMENTS," DATED JUNE 24, 1982 

BACKGROUND INFORMATION 

In most of the Solid State Protection Systems (SSPS) in the field, 
Westinghouse Type AR relays were utilized as the slave relays, and those 
requiring latch features were fitted with type ARLA latch attachments which 
perform the latch function by mechanical means. The manufacturer has 
discontinued the ARLA latch attachments, replacing it with a line of ARMLA 
latch devices which perform the latch function via magnetic means. The ARMLA
device, however, is an unqualified replacement fOr the safety grade SSPS. 
... An acceptable seismically replacement is a ... latching relay, 
especially qualified by Westinghouse and provided with an adapter base for 
mounting in place of an AR relay. This assembly (... with conversion 
mounting bracket) is identified as Westinghouse EMD (Hunt Valley) Part 
Number 2388A31. 

There have been reports that some plants, after ordering replacement ARLA 
attachments, have received (and may have installed) unqualified ARMLA 
attachments. 

RECOMMENDATION 

All affected plants should review their replacement and spare records to 
make certain that no ARMLA devices have been installed, or are in spares, 
for safety grade applications. Our initial evaluation concluded that 
malfunctioning ARMLA devices could have no adverse impact on safety. 
However, review of new information has revealed the potential for spurious 
latching, or malfunctions which could prevent latching or unlatching when 
required. Although the NRC is aware of this information, neither they nor 
Westinghouse have sufficient information to clearly identify affected 
plants. Therefore, Westinghouse recommends that utilities which have 
installed ARMLA devices in the protection system consider reportability to 
the NRC. ARMLA magnetic latch attachments have a gold colored (brass) 
plunger protruding from the latch assembly, whereas the ARLA plunger is 
greyish or off-white non-metallic material. 

Spare or replacement requirements should be filled by the Westinghouse-
qualified ... latching relay here no ARLA device is available. 

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