ML20195K412

Forwards Response to NRC 980821 RAI Relating to License Amend Request PCN-459 for Digital Radiation Monitoring Sys. Supporting Info & Calculation,Encl

ML20195K412
Person / Time
Site:	San Onofre
Issue date:	11/23/1998
From:	Scherer A SOUTHERN CALIFORNIA EDISON CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20195K417	List: ML20195K412 ML20195K436
References
TAC-MA0234, TAC-MA0235, TAC-MA234, TAC-MA235, NUDOCS 9811270012
Download: ML20195K412 (43)

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,k,,,j E DI SO N M"L,m An LD1504 IMERN4110%AL* Ganpaq November 23, 1998 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D. C. 20555 Gentlemen:

Subject:

Docket Nos. 50-361 and 50-362 Response to Request for Additional Information Regarding Proposed Change Number (PCN) 459 (TAC Nos. MA0234 and MA0235)

Digital Radiation Monitoring System (DRMS)

San Onofre Nuclear Generating Station, Units 2 and 3 (SONGS 2 & 3)

References:

1)

Letter dated August 21, 1998, from James W. Clifford (NRC) to Harold B.

Ray (SCE),

Subject:

Request for Additional Information Related To License Amendment Request for Digital Radiation Monitors, PCN-459 (TAC Nos. MA0234 and MA0235) 2)

Letter dated October 17, 1997, from D.

E.

Nunn (SCE) to Document Control Desk (NRC),

Subject:

Docket Nos. 50-361 and 50-362, Proposed Change Number NPF-10/15-459, Radiation Monitoring System Digital

Upgrade, San Onofre Nuclear Generating Station, Units 2 and 3 By reference 2, Southern California Edison (SCE) requested amendments to the

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SONGS 2 & 3 facility operating licenses to permit digital radiation monitor installation for bcth t:31ns supplying the Containment Purge Isolation Signal (CPIS), and permit digital radiation monitor installation for both strains supplying the Control Room Itolation Signal (CRIS).

By reference 1, NRC staff requested additional supporting information regarding the SCE request. Enclosure 1 contains the requested supporting information.

1 Additionally, provided as Enclosure 2 is a revision to the Engineered Safety

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Features Actuation System (ESFAS) Radiation Monitoring System (RMS) Single

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Failure Analysis, SCE Calculation J-SPA-269.

This calculation was revised to l

address hardware and software failures in the communication link between the safety related RMS and the non-safety related Digital Acquisition System (DAS).

It was determined that there were no single hardware failures that could disable the safety function of any ESFAS radiation monitor channel.

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San Clemente, CA 92674-0128 949-368 7501 Fa 949-368-7573 L

Document Control Desk The communication link software design was found to have multiple design features which provide protection against a' single software failure affecting any ESFAS radiation monitor channel. Although no known single failure was found that could disable a single channel of an ESFAS monitor, for conservatism it was assumed that an unknown software interaction could exist that would disable a single ESFAS monitor channel. Even under this unlikely scenario, it was determined that there would be no effect on the ESFAS safety function since the redundant ESFAS channel remains operable.

Finally, these additional analyzed single failures do not affect the Sof tware Common Mode Failure Analysis, J-SPA-289, since that document assumes all ESFAS RMS channels are disabled by an unspecified common mode software failure.

If you have any additional questions on this subject, please call me.

Sincerely, p

o Enclosures cc: E. W. Merschoff, Regional Administrator, NRC Region IV J. A. Sloan, NRC Senior Resident Inspector, San Onofre Units 2 & 3 J. W. Clifford, NRC Project Manager, San Onofre Units 2 and 3

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i ENCLOSURE 1 RESPONSES TO NRC QUESTIONS j

San Onofre Nuclear Generating Station L'

Units 2 and 3 1

Digital Radiation Monitoring System' i

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INTRODUCTION This document is in response to the NRC (Nuclear Regulatory Commission) request for additional information in a letter dated August 21,1998 from Mr.. lames W. Clifford, Senior Project Manager, to Mr.

. Harold B. Ray, Executive Vice President, Southern California Edison.

The information in this document is in support of San Onofre Nuclear Generating Station Amendment Application Nos.171 (Unit 2) and 157 (Unit 3), which consist of Proposed Change Number 459 (PCN.

459), requesting revisions to the Facility Operating Licenses to permit digital radiation monitor installation l

for both trains supplying the Containment Purge Isolation Signal (CPIS) and for both trains supplying the l

Control Room Isolation Signal (CRIS).

Responses to the seven questions from the NRC letter dated August 21,1998 are provided below.

RESPONSE TO NRC QUESTIONS

)

The first two questions are as follows:

1.

Describe the Digital Radiation Monitoring System (DRMS)3 with particular emphasis on the microprocessor hardware, interfaces, and communication features. The description of the software provided in your October 17,1997, letter provides sumclent information and need not be repeated.

2.

Describe the internal system architecture and its interconnections with external systems.

In order to adequately answer the above requests and ensure complete understanding of the Digital Radiation Monitoring System (DRMS), it is necessary to approach the subject in a layered fashion. To present this material in such a format, a combination of requests I and 2 is required. This is due to the fact that a di::cussion involving request number 1 would presuppose the reader of this document would have sufficient knowledge of the subject matter discussed under request number 2.

An overview of the DRMS system has been included as well as descriptions of key subsystems.

Diagrams have been included to enhance understanding where appropriate.

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P Overview of the DRMS The Digital Radiation Monitoring System (DRMS) is designed to provide reliable and accurate data to plant personnel regarding the radiological conditions which exist throughout Unit 2. Unit 3, Common Areas between the units, the South Yard Facility and the Multi-Purpose Handling Facility. The DRMS system is comprised of the following 3 major sub-systems:

Digital Radiation Monitoring System (DRMS)

The DRMS includes the radiation field units and associated equipment for the process and effluent systems and the centralized DRMS Control Panels for both the Main Plant and South Yard Facility. The DRMS also contains a specialized interface Local Processing Unit Input-Output (LPU/lO) to connect existing radiation monitoring equipment that are not being replaced with l

MGPI (MGP. Inc.) equipment, Wireless Area Radiation Monitoring System (WARMS) e The WARMS employs RF technology to collect area radiation data and conveys the data to the Data Acquisition System (DAS). The only area that utilizes the WARMS technology is the South Yard Facility. This system is not discussed in this response.

Data Acquisition System (DAS)

The DAS is comprised of Supervisory Control and Data Acquisition (SCADA) nodes which are attached together to form a Local Area Network (LAN). The purpose of the DAS is to collect the various DRMS data inputs and present it in a Graphical Unit Interface (GUI) format for viewing by plant personnel. The DAS is responsible for transmitting annunciation signals to the Control Room which originate from the WARMS and the DRMS. The DAS also provides data storage capabilities and an interface to the existing Emergency Response Data System (ERDS).

The following figure is a basic block diagram of the DRMS:

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General Description of the Data Acquisition System The Data Acquisition System (DAS) provides the system operators with near real time data from the distributed DRMS field units and the SYF Wireless Area Radiation Monitoring System (WARMS).

This data is collected by the DAS, processed into usable information and made available to the operators in the Control Room and other specified locations. The DAS allows for archiving and retrieval of the historical data for future reference and provides an interface for other plant systems.

There are five major types of equipment, each with a specific function in the overall functionality of the DAS. The DAS is non-safety related.

I/O Equipment There are two types ofI/O assimilated by the DAS. The first is the analog and digital I/O that are managed by the RTP (Real Time Products, Inc.)l/O interfaced to a SCADA Node. The second is the RS-485 (DRMS Monitors) and RS-232 (WARMS) serial data. These signals are managed using a specialized interface board in the SCADA Node. The RS-485 signals are converted to RS-232 before the interface is made.

• SCADA Node The SCADA Node is comprised of an IBM type computer running specialized data acquisition software. This software receives data from associated I/O equipment and maintains the data in a database making it available to operators using View Nodes.

• View Node The View Node is comprised of an IBM type computer running specialized data acquisition software. The View Node software consists of a set of user configured GUI screens providing a graphical representation of various aspects of the DRMS (Digital Radiation Monitoring System).

These screens have links to specific fields in the SCADA Node database. When a screen is active the associated data from the database is displayed.

• Data Achiever The Data Achiever is a VAX computer running custom software modules designed to collect data from the SCADA nodes and store that data in historical files. The data remains accessible to system nodes with reporting capabilities.

• DAS LAN The DAS LAN is the isolated network infrastructure that allows for communications between the SCADA Nodes. View Nodes and Data Achievers.

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l The DAS includes seven functional areas:

input / Output e

l The Data Acquisition System is divided into sub-systems for Unit 2 Unit 3 and the South Yard Facility. Each sub-system provides the data acquisition and control functions for the DRMS field units associated with the respective area of the plant. Common DRMS field units, or those not specific to an area of the plant, are all managed by the Unit 2 DAS sub-system.

Signals from the MGPI field units are received into the DAS in two different ways:

Signals from the MGPI field units (RDU/LPU and LPU-UOs) are handled by five dedicated RS485 networks. Each network is configured with a SCADA Node as the master device and i

the field units as slave devices.

Signals from non-MGPI area monitors are handled by a five Real Time Products (RTP) UO

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chassis. Each chassis communicates with a SCADA Node via an RS232 asynchronous serial 1

link.

Data Acquisition Information from the FO equipment is assimilated by the SCADA Nodes. A SCADA Node is an IBM type industrial computer running the FO drivers and Intellution FIX 32 software, a SCADA software program. FIX32 processes the information into usable data and makes it available to the DAS operator for viewing, trending and archiving.

j Data Display After the data has been collected by the SCADA Node, it can be viewed by the DAS operator at any of the DAS View Nodes or SCADA Nodes. The DAS View Nodes, also IBM type industrial computers running Intellution's FIX 32, provide the DAS Man / Machine Interface (MMI). View Nodes display the data collected by the SCADA Nodes using a graphical user interface. The SCADA Nodes and the View Nodes communicate using the DAS LAN. Each View Node is configured to provide current value, alarm state, trend data, equipment status for the system, and alarm notification when system parameter limits are exceeded. Additionally, the View Node gives the Operator the ability to initiate certain control sequences on non-safety related monitors such as pump control and filter advance. Access to certain features is controlled by the implementation of security levels.

• Communications The DAS utilizes Token Ring and Ethernet protocols to enable the DAS computers to communicate with each other. The system is divided into four main areas to provide maximum availability without loss of data. The four segments are divided into two Token Rings and two Ethernet segments.

Two Synoptic Hubs, one for Unit 2 and one for Unit 3, are used to manage system communications. Each hub manages one Token Ring and one Ethernet segment and provides the bridge between the associated Unit's Token Ring and that of the opposite unit. This ensures a communications redundancy and therefore a high degree of availability of data assuming a communications failure on either of the two Token Rings. The Synoptic Hubs also route communications between the Token Ring LANs and the Ethemet segments.

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The Unit 2 Token Ring communications are routed to the U2 Ethernet while Unit 3 Token Ring communications are routed to the U3 Ethernet segment. There is no direct bridging between the Ethernet segments. The Unit 2 and Unit 3 VAXs are located on their respective Ethemet segments.

Data Storage Both the Unit 2 and the Unit 3 DAS VAX computers provide long term data storage. The Unit 2 and common DAS data is stored on the Unit 2 VAX and the Unit 3 and SYF (South Yard Facility)

DAS data is stored on the Unit 3 VAX Primary SCADA and Secondary SCADA data from a given unit is sent to the VAX where it is merged, validated and stored in spreadsheet file format.

The data can then be accessed as historical data.

Emergency Response Data System Interface The VAX computers also serve as the DAS to ERDS (Emergency Response Data System) interface. Data is downloaded to the DAS VAX computers from the SCADA nodes and stored on the DAS VAX in a data collect file. This file is separate from the data merge file created for historical data archival. Periodically, data from the collect file is read by ERDS and transmitted on to CFMS (Critical Functions Monitoring System).

• Annunciation Interface The DAS provides annunciation to the Control Room to alert operations personnel to changes above predetermined setpoint values, which are controlled by the DRMS (Radiation Monitoring System). The exception to this is activation of Engineering Safety Features, operated by Safety-Related monitors. This annunciation provided to the control room is made through a hard-wired contact.

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General DescriDtion of the DRMS l

The DRMS (Digital Radiation Monitor System) inciudes the field units and the centralized DRMS Control Panels located in the Control Room Hallway. There are two categories of field units:

• Process Monitors Process Monitors are der ud to provide radiological information related to certain plant processes and to aid the operator's evaluation of the functional performance of various plant systems. They are intended to provide early detection of system fluid leakage from radioactive plant systems to normally non-radioactive plant systems in certain facility locations. Also, the process monitors provide continual surveillance to indicate abnormal changes in activity of the process stream.

• Emuent Monitors f

Effluent Monitors provide radiological data for the plant systems that discharge to the enviromnent to ensure that the radioactive components of these effluents do not exceed applicable f

plart or regulatory release limits. The Effluent Monitors continuously monitor these systems and 1

pros ide operator alarms and/or automatic isolations when prescribed limits are exceeded.

The DRMS includes 21 radiation process and effluent monitors providing information from both Unit

2. Unit 3 areas and systems and the South Yard Facility. The areas and systems monitored are the Containment Building Environment Radwaste Condensate Return, Blowdown Processing System i

Neutralization Sump, Turbine Sump, Component Cooling Water Systems, Fuel Handling Area Vents and Control Room Environment. Some of these systems have redundant monitors to provide for the continuous availability of reliable radiological information. Some of these monitors are safety-related monitors, as determined by the function they perform.

The DRMS consists of an array of radiation monitoring field units located throughout the Main Plant 1

and SYF (South Yard Facility). The field units collect and process data into useful radiological information that is made available to the centralized control panels located in the Control Room area.

The field units detect radiological conditions exceeding predefined thresholds and alert the operator to the condition. Certain system control functions such as set point modifications and system actuations

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can be performed using a display unit at the monitor field unit or at the centralized control panel, i

l Historical data archives are maintained by the DRMS to allow trending and data comparison.

Additionally, the DRMS is equipped with self-check routines, redundant safeguards, and system status indications to ensure proper system operation, all to verify the integrity of the information being provided to the Operator. Standard conununication protocols and interfaces allow the safety related DRMS to transmit data to the DAS. Non-safety related DRMS monitors may also receive instructions from the DAS.

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The 21 Main Plant Process and Effluent Monitors utilize five basic skid / monitor designs. The j

following table describes each monitor channel and the type of monitor utilized.

Channel Number Channel Description Monitor Type I

2RE7804-1 Unit 2 Containment Air Particulate and Noble Monitor Gas Skid 3RE7804-1 Unit 3 Containment Air Particulate and Noble Monitor Gas Skid 2RE7807-2 Unit 2 Containment Air Particulate and Noble Monitor Gas Skid 3RE7807-2 Unit 3 Containment Air Particulate and Noble Monitor Gas Skid i

2/3RE7808 Unit 2/3 Plant Vent Extended Range Noble i

Stack Monitor Gas Skid 2/3RE7812 Radwaste Condensate Off-Line Liquid Return Monitor Monitor 2/3RE7813 Radwaste Discharge Off-Line Liquid Line Monitor Monitor 2RE7817 Unit 2 BPS Off-Line Liquid Neutralization Sump Monitor Discharge Monitor 3RE7817 Unit 3 BPS Off-Line Liquid Neutralization Sump Monitor Discharge Monitor 2RE7819 Unit 2 Component Off-Line Liquid Cooling Water Monitor Monitor 3RE7819 Unit 3 Component Off-Line Liquid

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2RE7821 Unit 2 Turbine Sump Off-Line Liquid Discharge Radiation Monitor Monitor 3RE7821 Unit 3 Turbine Sump Off-Line Liquid Discharge Radiation Monitor Monitor 2RE7822-1 Unit 2 Fuel Handling Noble Gas Skid Area Vent Airborne Monitor 3RE7822-1 Unit 3 Fuel Handling Noble Gas Skid Area Vent Airborne Monitor 2RE7823-2 Unit 2 Fuel Handling Noble Gas Skid Area Vent Airborne Monitor 3RE7823-2 Unit 3 Fuel Handling Noble Gas Skid i

Area Vent Airborne Monitor 2/3RE7824-1 ControlRoom Airborne In-Duct Monitor Monitor 2/3RE7825-2 Control Room Airbome In-Duct Monitor Monitor SYF7904 South Yard Facility Particulate Monitor Effluent Monitor SYF7905 Decon Enclosure Particulate Monitor Effluent Monitor S

The basic layout of the RMS system and its interconnection to the DAS is represented in the following block diagram-7

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DRMS Display and Control The DRMS provides the system operator with an interface for parameter configuration, data retrieval, and system control. Display and control within the DRMS is accomplished in four ways, each having specific capabilities and limitations:

Local Display Unit Each field unit includes a Local Display Unit (LDU) which provides dirplay and control capabilities at the monitor (s). The LDU provides access to real time and archived data, indication of alarm conditions, equipment status, control capabilities, and limited configuration capabilities.

The LDU also provides communications for remote and external data display, control and acquisition.

DRMS control Panels / Remote Display Units Centralized display and control consoles or cabinets are designed to house Remote Display Units (RDU) for the DRMS field units. These RDUs perform similar functions as the LDU. The cabinets are located in the Control Room area where centralization of the information from the distributed field units is required. The cabinets can contain one or two RDU chassis, with each chassis holding up to 5 RDUs each. The cabinet also contains trend recorders for trending Radiation Monitor indications.

Portable Maintenance Computer The Portable Maintenance Computer (PMC) is a portable notebook computer running a software module called Maintenance and Setup Software (MASS). The PMC can be taken into the field and connected to an LDU via the RS-232 interface or directly to an LPU using a RS 232/485 converter. The PMC can then be used to perform high level parameter configurations, data analyses, system diagnostics, troubleshooting or failure recovery, DAS SCADA & Vlew Nodes e

(See DAS discussion)

LPU Functional Description The Local Processing Unit (LPU) is the main processor for any given DRMS channel. It amplifies, shapes and processes the signals generated by the associated detector using practical algorithms and detector specific software. The resultant data is transmitted to display units via an RS-485 network connection. The LPU also provides storage for the configuration and setup parameters for the detector channel.

The LPU is a basic element in the DRMS system and is connected to a power supply circuit, a radiation detector and one or two RS-485 field bus communication networks. The main function of the LPU is to process the signals from the applicable detector and to provide storage of the historical data.

The LPU can control relay outputs and, as an option, process 0-20 or 4-20 mA analog inputs / output.

The LPU software configuration can be modified via one of the two RS485 links to a PC equipped with the MASS software.

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Features Associated With the LM'/ PIPS /P The LPU/ PIPS (Local Processing Unit /Passivated Implanted Plarier Silicon) is equipped with a PIPS CM' board connected to the detector head. The CM board carries out the interface between the LPU and the PIPS detector, with a connection for and input from a flowmeter. The flowmeter measures the sampling rate. These elements are part of the monitor associated with this type of LPU. He PIPS CM board with the particulate (PIPS /P) option also carries out the interface with the power operated filter paper drive. On the panel there is an 8 pin connector for the probe and two 4 pin connectors, one for the flowmeter and one for the power operated cassette (The gas PIPS has two connections, one for the probe and one for the flowmeter). The power-operated paper drive is supplied with power from the

- LPU/ PIPS. This element is part of the monitor associated with this type of LPU.

Features Associated With the LPU/SAS The LPU/SAS/Na! (Local Processing Unit / Spectrum Analysis System) is equipped with a CM Nat (Measurement Board. Sodium Iodide Type) board integral to the heal The CM Nal board carries out the interface between the LPU and the Na! detector using a 5 pm connector. This board processes the data which come from the radiation detector and from a temperature probe. The temperature probe measures the temperature of the NaI Probe. This LPU is also equipped with 2 boards called ACQ' (for acquisition) and SPT' (for spectrum). The ACQ board is intended to measure the energy of each pulse processed by the CM Nal board. The Sirl' board counts the number of occurrences for each energy. A radiator type heat sink, fixed on the upper part of the LPU, ensures the dispersal of excess thermal energy.

Features Common to all LPUs The LPU is made up of a basic module with several options. He basic module contains the following features:

Scaled unit conforming to IP 655 standards which ensures complete protection from dust and water.

Six (6) pin plug to connect to the power supply network.

Nineteen (19) pin plug to connect to the different LPU signal connection.

Grounding pin allowing the unit to be grounded.

AC/DC conversion block which provides the necessary electrical power for the system and electrical insulation from the power supply network. This bor.rd is found behind the bus support plate.

l A plate mounting the bus board.

l A " bus " board which transmits a G96 format bus to the 5 board slots. Each board slot also 1

includes a heat sink connected to the box. The bus board allows communication between different I

system boards.

A power supply module (MA' board) provides the bus with a power suppy of +/-5V and +/-15V.

It automatically switches to the battery in the case ofloss of power for greater than 150 ms. The MA board provides three outputs, one relay and two RS-485 isolated interf aces. An optional daughter board provides two outputs and an analog input on isolated current loops. The MA board exists in two versions: low and high power consumption. The latter is used on the LPU/SAS.

A processing module (CT' board) which controls the bus. It carries out the management of the l

other boards, calculation, analog and digital outputs. It also stores operational parameters, the sequence of checks and the different programs necessary for the application. The storage of the parameters and programs is carried out by " flash" memory (unlimited retention). The data is protected for 3 months by the battery.

' CM, ACQ, SPT, MA, and CT are merely identifiers for a particular component within the LPU. It has no intrinsic meaning.

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Electrical Interfaces to the LPU Two (2) RS-485 type communication lines,500V insulatio s e

Two (2) Relays: 250VAC,10A,2000V insulation. Single pot.u.ble throw type. Option: 3 e

Single pole / single throw type relays.

Analog 1/0 (optional): 2 analog outputs and I analog input:

Two (2) analog outputs: 0-20 mA or 4-20mA configurative using software. 500V insulation..

One (1) analog input: 0-20 mA or 4-20 mA configurative using software. 500V insulation. Input impedance: 22 ohms.

Detailed Description of the Boards Contained within the LPU The LPU is modular and is made up of easily replaceable boards:

The measurerr nt board (CM) carries, for certain types, the detector and an EEPROM memory containing al, a parameters linked to the detector. This board interfaces with the detector, and provides the

>1ification, shaping and the digitization of the signals. This board is connected to the front par.H The acquisition boud (ACQ) and a spectrum board (SPT) for the SAS version only. The ACQ e

board carries out the analog / digital conversion of the pulses coming from the CM board, and the SPT board carries out the sequencing and the management of acquisitions and the storage of the spectrum.

The processing board (CT) manipulates the data coming from the measurement board, manages e

the two external serial links, and manages the three relays and the two analog outputs.

2 A location has been allotted for a communication board (CC ) carrying out the interface with the industrial local network (FIP or EliTERNET version) or optic fiber. This board is only used when the two available serial links on the CT board do not meet requirements.

The main board supports the G96 bus and connects to the box.

e The input / output insulation and power supply module (MA). This module is insulated from the electromagnetic influence of the other boards. This module receives a 16V power supply, supplies SV, +/-15V voltages, the two relay outputs, galvanic isolation of the outputs, the analog input and the two serial links. This modale contains the battery which will provide power for all the system if the power supply network goes down for less than 150 msec.

The CT board and the MA module are the same for all the LPU types. The CM board is adapted to the type of detector in question and characterizes the LPU. The CM. CT, SIrr and ACQ boards communicate between themselves via a standard G96 internal bu:.

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CC is merely an identifier for a particular component within the LPU. It has no intrinsic meaning.

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LDU General Description The LDU (Local Display Unit) is a basic unit of the DRMS. It provides rhe local operator interface for the DRMS filed units. It receives data from the associated LPU(s) and n akes it available to the operator using a display screen on the unit. A keypad allows the operator to change the display and modify parameters. The LDU also makes DRMS data available to the operator via an RS-231 link on the front of the unit. This requires a Portable Maintenance Computer (PMC) using the Maintenance and Setup Software (M ASS). Data can also be made available to other Display Units or to an external system such as the Data Acquisition System.

RDU General Description The RDU (Remote Display Unit) provides similar capabilities as the LDU but it is designed to be remotely located in a display and control panel. This gives the operator access to DRMS data at a centralized location such as the Control Room.

I FP Interface Boards (25M and 5M) General Description i

3 The FP interface boards are used in control panels to provide an electrical interface for the RDU. The 25M board provides a common back plane for up to five RDUs. The SM board provides an interface for only one RDU but allows multiple boards to be daisy chained into a network. The FP board is typically mounted on the back of an RDU chassis. The 96 pin connectors on the back of the RDU mate with connectors on the front of the board. Connectors on the back of the board provide an interface for the field wiring.

LDU Functional Description The LDU is a basic element of the DRMS system. It is connected to an RS-485 digital communication network and can be connected to a master network (Data Acquisition System, RDU, or other LDU) and a slave network (LPU, LDU). The LDU is a wall mounted or skid mounted unit designed for local operation. Its main function is to transfer the measurements carried out by the LPU. Depending on the measurements from the LPU, the LDU can generate audible, visual and relay alarms. It can also activate digital relay outputs and read digital inputs. Through these digital input and output functions.

the LDU can manage simplified programmable logic controllers. In addition, the LDU is equipped with either 0-20 mA type or 4-20 mA type analog inputs and outputs (depending on the configuration).

'Ihe LDU is configured through the RS232 type serial link connected to a PC equipped with the MASS software.

The LDU has several options. The basic module consists of:

A dust and water jet proof housing to IP 655 standard Four (4) wall attachment points.

3 FP is merely an identifier for a particular component associated with the RDU. It has no intrinsic meaning.

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A six-pin MILC 38999 connector for connection to the main power network.

e 19 cable glands for connection to the LDU terminal blocks.

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A stud for grounding the housing.

• A lock for the door, A nine-pin connector for configuration through a PC equipped with the MASS software (RS232 e

serial link).

A battery backup that protects against loss of digital memory data during power transients.

A power ON indicator light.

• An On/Off switch.

e Four fuses.

A grounding strip.

The main board (CRI' board) which ensures connection to the user terminal blocks plus the power alarm relay functions and the DC power supply to the different boards.

The AC/DC power supply module that supplies the power required by the system plus electrical e

isolation from the power supply network.

OptionsInclude:

A digital I/O board with 16 inputs and outputs.

An LPU copy terminal block for connection to the different LPU functions.

Two analog outputs and an analog input.

Three indicator lights, A flourescan graphic type display with 64 X 240 pixels resolution.

e A keypad with three keys and five LEDs for LDU indication signaling.

• A buzzer A thermal switch that cuts off the LDU power supply if the tc.mperature exceeds a threshold which e

is critical for the service life of the equipment. This threshold is set at 131 'F from the ambient temperature.

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Detailed Description of LDU Printed Circuit Boards The LDU is built around 3 printed circuit boards, one of which is optional:

The Data Transfer Board (CRI Board) manages processes based on data from: the 16 digital e

inputs, the analog input, the 4 serial links connected to the DRMS network and the configuration i

keyboard.

The CRI board also transmits data from associated slave devices to the 240 X 64 graphic screen, the indicator lights and buzzers, the 16 analog outputs and the 2 digital output and the 4 serial links.

Terminal Block Backplane Board (FPB Board) provides connections, through screw type terminal e

blocks, to the CRI board analog and digital inputs and outputs, to the power relays (Test, Operate, Alert, High, High/high) and to the source test relays.

It also provides the different power supplies to the LDU printed circuit boards and sub-assemblies during normal operation and power transients.

Digital I/O Board provides 16 digital inputs and outputs connections by means of screw type terminal blocks.

• CRI is merely an identifier for a component existing in a Display Unit assembly. It has no intrinsic meaning.

13 e

The following diagram depicts the internal components of the LDU and their interfaces to each other:

i RS232 i

Connector foi PMC/ MASS

) k if A

Keypad m

Power Connection CRI Board s-r VFD

) k 1 f If Filter Fuses ON/OFF Switch

\\

r

) k I

FPB Board I I AC/DC w

DigitalI/O Board m

r m

Converter l

<ssae vgio se

) k if 1

M Terminal Blocks s, I

1 14

i CRI Board Description The CRI board is a smart board built around a microprocessor and is common to the LDU and the RDU. All data is stored in backed up RAM and Flash memories, even in the event of a main power failure. The software can be downloaded using a PC through the RS232 or RS485 serial links which makes for rapid, sure maintenance. A clock dates events such as power up and equipment shutdown, alarms, etc.

The following diagram depicts the internal components of the CRI Board and their interfaces to each other:

s 12Mih

)

G96 Bus s '

Processor 96 PM

(

24 Milz Interface 7

)k Y

t LSAs

( )

9 Pin O PMC/ MASS Q

(3 RS485 and i Watchdog RS232)

(

)

Power Reset

( )

Relay Conunands st sL 1ADC s

s Digitalinputs

'r

' r 12 Bits *

• FPB or Digital 1/O I >

50 Piri DAC Board u

8 Bit ADC 2 x 12 Bit Power and Temp 7

'7

'7 Channels **

96 Pin O FPB Board s

Buzzer with self a'

'5 Self Test Relays timer

'7

' r r

Realtime Clock Timer Bus arxl Address g

3 Indicator Light

)

Controller Commands 4

a s

st 3 Source Test t

' r r

Relay Commands EPROM Bac kup RAM 121 ash EEPROM 64K x 16 to 64K x 16 to 64K x 16 to Q

8 Digital Inputs (

256K x 16 256K x 16 256K x 16 Graphics Display Keypad, Status s

s Keypad r'

10 Pin ss st r'

34 Pin Q VFD r

and Alarm LEDs 'qpr Bus 1

15

FPB Board Description The FPB board delivers the +5V, +/-15V and +12V power supplies to the LDU and maintains these voltages for 150 ms in case of power transients it transmits the operating status and alarms on five 4PST (4 pole single throw) relays and ensures user connection to the interface, to the above relays, to j

the three DPST (double pole single throw) source test relays and to the CRI board functions (serial links, analog 10).

The FPB board includes:

Relay outputs: 5 "high EMI immunity" 4PST relays (3 PST if the data transfer function is used),

e are fitted on the board. They are controlled by the CRI board through a power interface. Three other DPST (double pole / single throw) relays are used for the source tests and are also controlled by the CRI board.

Indicator lights interface: Three power transistors controlled by the CRI board provide the LDU indicator lights interface.

Terminal block: All LDU functions (three 485 serial links, five data transfer relays, three source e

tests, two analog inputs and one analog output, three indicator light power interfaces) are available i

at a screw type terminal block on the FPB board. Each terminalis identified by a number between I and 120.

I i

l 16

The following diagram depicts the internal components of the FPB Board and their interfaces to each other:

12 V DC '

Battery Charging 12 VDC Regulator and System Switching Power Supply 4 >

4 Pin

)(

)k 0- \\ R V DC w

w DC/DC Converter (9-18 VDC to AC/DC C)

)(

(

s w

q

+5, + 15, -15 VDC:

3 Converter

)(

) k CRI Beard < >

50 Pin 4 Buzzer m

< > Battery

+5, + 15. -15 VDC Digital 1/O q y Board 26 Pm, Buzzer m

< > Buzzer J L 8 DigitalInputs 1f a

3 LS As (RS 485) j m

e 2 Analog Outpus and 1 Analog Input a

q y

Power Relays 4

CRI Board 4 >

and Self Test 96 Pin 3 indicator 1.ichts 7

> Indicator Lights DrWr w

2 w

3 Source Test Relay Options 17

Digital I/O Board Description The Digital 1/0 board provides 16 analog inputs and 16 analog outputs. It includes:

Digital inputs insulated by optocouplers. Each group of 8 inputs is supplied by a DC/DC insulated converter which makes direct use with a simple contact possible (e.g. open/ closed relay contact).

Digital outputs consisting of 1-make contact relays plus the control electronics.

A screw type tenninal block for user connection to the inputs and outputs. Each terminal is identified by a number between 1 and 72.

The following diagram depicts the internal components of the Digital I/O Board and their interfaces to each other:

8 Digital inputs FP8 1

8md

+ 5 VDC DC/DC Insulator

+-+

26 Pin n

15 VDC Power Supply n

16 Digital Power j

a j

Cable Relays inn:

+--+

Option Gland E

E t

3 E

E Relay Control o

o 5

g g Interface "a

7 0 j

i u

n_.J L._n J

n CRI 8 Digtalirputs 8 Digitalinput

-50 Optocoupler Board Pn e-o 18

RDU Functional Description The RDU has the same main functions as the LDU with the exceptiori of:

The size and shape of the housing.

e The number of digitalI/O.

e The status, alarm and Digital 1/O cutoff capacity.

The source test relays.

The indicator lights The RDU is connected to an RS485 type communication network and so can be connected to a master network (central computer, RDU) and to a slave network (LPU, LDU). Unlike the LDU, the RDU is designed for centralized operation and is fitted in a cabinet. Its main function is to transmit the measurements carried out by the LPU. Depending on the LPU measurements and its configuration, the RDU can generate visual, audible and relay alarms. It can also activate relay outputs and read digital inputs. Through these input and output functions, the RDU can manage simplified programmable logic controllers.

For the RDU, digital status alarm relays cutoff capacity is limited to 60 VDC,0.6A for a resistive load.

j Like the LDU, the RDU is equipped with 0-20 mA (or 4-20 mA depending on programming) analog inputs and outputs.

The RDU is also configured through the RS232 serial link connected to a PC equipped with the Mass software.

The RDU consists of a basic module plus several options. The basic module includes:

• A 5/25M wide chassis.

A 9-pin connector for configuration using a PC equipped with the MASS software (RS232 serial link).

A battery for memory data backup which protects against power transients.

• An ON/OFF switch.

Two (2) fuses, A grounding strip.

e The main board, CRI which includes the microprocessor. It manages all RDU functions:

memorization, network management, analog and digital 1/O commands, user interface (display, keypad, signaling).

The PWR board which regulates and converts the DC power supply for the different RDU boards and components and ensures the relay output function.

The AC/DC power supply module which ensures the power required by the system plus electrical isolation from the power supply network.

The options include:

The two analog outputs and the analog input (function provided by the CRI board).

A fluorescent type graphic display unit with 64 x 240 pixels resolution.

A keypad with three keys and five LEDs for LDU status and alarm signaling. This keypad is available in two versions, one with a transparent window for a VFD type graphic display unit, the other without window. There are two keys for screen selection and one buzzer validation acknowledgement key.

• A buzzer.

A thermal switch which cuts the RDU power supply if the temperature exceeds a threshold which is critical for the service life of the equipment. This threshold is set at 131 'F from the ambient temperature.

19

Detailed Description of RDU Printed Circuit Boards The RDU is built around 2 printed circuit boards:

The Data Transfer Board (CRI board) manages process based on data from the 8 digital inputs, the analog input, the 4 serial links and the configuration keyboard.

The CRI board transmits the data from its associated slaves to the 240 x 64 graphic screen, indicator lights and buzzers, the 8 analog outputs and the 2 digital outputs and the 4 serial links.

A power supply board (PWR ) which provides 8 digital outputs, different power supplies to the RDU printed circuit boards and subassemblies during normal operation and during power transients and 8 digital outputs (the 8 inputs are on the CRI board).

The RDU boards use the following types of connectors:

i CRI board and PWR board to backplane board (5M FP or 25M FP) connector: 96-pin DIN 4!612 e

type.

1 CRI board to RS232 connector: 9-pin SubD type e

PWR board to display unit connector: MOLEX 4-pin 6471 type j

e PWR board to battery, buzzer, AC/DC unit: MOLEX 3-pin 5195 type.

e All other connectors are the IIE1010,26,34 and 50-pin types.

e A detailed discussion of the CRI board has already been presented in the description of the LDU. The boards are identical in function; henceforth this information will not be repeated.

PWR Board Description i

The PWR board delivers the +5V, +/-15V and +12V power supply voltages to the RDU and maintains the signaling for 150 ms in the event of a power transient. It supports the eight single-pole-single-

)

throw digital output relays.

i 20

The following diagram depicts the internal components of the PWR Board and their interfaces to each other:

12VDC I

8'"Y C h8i"8 12VDC mg, igg -

and System Swirtung Power Supply 4-)

4 Pla N

k-l l

+5VDC i

i 3 Pin (->

Battery y

Tenn.f

.18VDC 2 Way DCDC Convener '

ACDC 4->

(9-18 VDClo Conmter Block j

+5, +15,15 VDC)

/-15 VD Backup R AM Pour k 3 pla (->

Buzzer 8"***'

CRI Board 4-> 50 Pin (

)

Relay Corurol 8 SPST Dig' al e

Power Relays 8 Digitalinpuu k

V y

c:nSever4-> o f,.,e

=

3 4-Pu.e dlt

]

i i

Y y

V 96 Pin 1

A, Y

FP Board l

I l

21

Backplane Board (FP) Description The RDU must be fitted in a rack and connected to a backplane (FP) board. These FP boards redistribute the RDU internal functions (serial links, digital and analog 1/o, etc...) to other units (LDU, RDU, LPU, central computer, users, etc...), in order to deliver the main supply to the RDU and to bias and match the serial links.

There are two types of FP board:

e SM FP board for one RDU (Used exclusively at San Onofre) e 25M FP board for five RDUs (Not used at San Onofre)

SM FP Board Description This board is used for one single RDU. Ilowever, it is possible to fit these boards side by side on the same rack in order to take 5 RDUs.

The user side of this board contains nine connectors:

10-pin connectors which delivers the RDU master link, its two slave links and its two analog outputs.

A 10-pin connector which delivers the RDU ma:,ter link and its two slave links if the link switches are configured and the analog input set.

A 10-pin connector which delivers the eight digital inputs.

Two 10-pin connectors which deliver the eight digital outputs.

A 10-pin connector which delivers the "self-test" signals for the user-specific and external data transfer relays.

Two 15-pin connectors which deliver the two switching systems (2PST) for the five data transfer relays (OP, TEST, ALERT,IIIGil,111G11/111G11).

A 10-pin connector which delivers three serial links. The first iint corresponds to link the five master links (RDUI to RDUS). The second and third links correspond to link the five RDU slave links identified by the same name as the RDUs. Link is defined if the link switches are configured.

A 3-pin main supply connector.

An ON/OFF switch is provided on this board to switch the RDU on or off.

\\

l 22

l 1

The following diagram depicts the connectors, Switches and their interfaces to each other for the SM Board; Anabg Inputs 10 Mn Lee LSA Matching EidL_s LSA Link Link Swith 2 Anabs Outpuu l

_p

__pf 10 Pin CRI Board g.

6 Mn 4 0 Pin External Relay Self Te s Swithing Equipment for

)

OP,1EST, A11RT, HIGH and HIGH IDGH Relays 15 Pin Swithing Equipment for

%l OP, TEST, AliRT,10GH armi HIGil-HIGil Rebys 15 Pin 1

](l Main Power 3 Way N

Sw.t h Term. Block Digital Relay Outputs 1-5 10Mn 96 Ma PWR Board 45 Digital Relay Outputs 6 8 l

~

10 Pin External Relay Power Supply l

l i

23

)

Electrical Interfaces to the LDU/RDU i

i Serial Link 1,2, and 3: type RS485 2 wires. 500V insulation j

e

• Serial Link 4: type RS232 on a 9 pin SubD9 connector, not ins.nated, protected against short j

circuits j

Options 2 analog outputs and I analog input (optional):

2 analog outputs:

0-20 mA or 4-20 mA, configured by software. 500V insulation. Acceptable load: 0 ohms to 1 Kilo-ohm.

I I analog mput:

0-20 mA or 4-20 mA, configured by software. 500V insulation. Input impedance: 22 ohms.

l LDU options,16 Digital inputs / outputs Digital output relays:

SPST 125VDC 0.3A and 250VAC 3 A on a resistance load Insulation: 100M ohms at 500V i

Dielectric: 2000VAC Digitalinputs:

Insulation by optic couplers, self powered +5V common.

Insulation: 100M ohms at 500V.

Dielectric: 500VAC RDU options,8 Digital inputs / outputs:

Digital output relays:

SPST 60 VDC 0.6A and 60 VAC 1 A on a resistance load.

Insulation: 100M ohms at 500V Dielectric: 500VAC l

l 1

I 24

Specific Description of the CPIS Monitor The Containment Purge Isolation System Monitor is designed to provide radiological information about the Containment Building strnosphere. The Particulate and N13/ Noble Gas Skid, model DRMS-8009-SR, configures a BPM (Beta Particulate Monitor) (LPU/ PIPS /P) and an N13/ Noble Gas Monitor (LPU/S AS) to provide continuous monitoring of the containment building atmosphere for Unit 2 and Unit 3 at SONGS. The Beta Particulate Monitor specifically monitors for beta emitting particulates. The N13/ Noble Gas Monitor (Nal detector) utilizes a Local Processing Unit / Spectrum Analysis System (LPU/S AS) to provide spectral analysis of the radioactive constituents in the sample gas stream. A Particulate and Iodine Sampler, mounted in parallel with the BPM, offers continuous monitoring of particulate and iodine radioactivity in the sample stream. This configuration is designed to provide radiological monitoring for the containment building atmosphere for detection of primary to atmosphere leakage. This monitor configuration is used for 2RE7804,3RE7804,2RE7807 and 3RE7807.

The following diagram depicts the sample flow path through the CPIS gas skid:

Sample Inlet V-8 Sample Outlet Grab Sampler V-7 y,9

]V-2 V-1 U

I Pressure Beta l Differential Switch Q Pressure Q

Particulate P/I Sampler i Monitor Switch v

U Pump V-4

[

V-5 Vacuum V-6

Dram, Switch g

Mass Flow Q

Noble Gas /N13 Meter

-O-V-12 V-3 Monitor Vent I

C 25

The Particulate and N13/ Noble Gas Skid includes 2 monitors. These are the Beta Particulate Monitor which consists of a Beta Particulate Detector Assembly with a LPU/ PIPS /P (Passivated Implanted Planar Silicon Particulate) and an N13/ Noble Gas Monitor which consists of a N13/ Noble Gas Detector Assembly (Nal Detector) with an LPU/SAS (Spectrum Analysis System).

The following drawing depicts the logical connections that exist between each of the major components on the Particulate and N13/ Noble Gas Skid:

r----------

---

i l

ll t

l Recorder l l 1

g' A01 A02 l

l l

Operate Relay l

LPU2

""Y

l Actuation l (545 ll RDU2 i

• To PC l i

Detector II RS232 :

l (Nat 2"x3")

ll SL3 %

t

+-4 Control l l

st2 Su Su St2 +

l ll

~

Room l

li j

Skid ll DAS-A -+

l l

ll DAS-B j

1 11 l

i Su +4Su SL2,

l 18 g

l DCtCCtor ll SL3 &

I p

To PC l (PIPS /P) iI RS232 LPUI li onni i

i Skid Flow Meter tI nuU1 (PIPS /P) iI H Relay

l Actuation l l 1

Filter Motor Control e

11 g

l lt Operate Relay 1

l 1

2 II AO)

A02 ll_4

l Recorder l l l To PC

• 1 RS232 I

i Press Diff. Switch

$=-- SLI SL2 +

L------------,

PDSH (PDS High)

DI4 i

PDSL (PDS Low)

DI3 D:5 4

I i

I (Man /OfflAuto) g l

1 LDU i

l.

ff Pump l Turn On/C 1

lVS l Pressure Smitch D12 Pump K l

l3 g

D01

'V l

Legend I

i PS j

Dil i

p r

ig Signal Flow l

l Reset Button l I

li i

g RS-485 i

j Pump l

i Turn Off

[

l Latching Relay P " "' ?

I I Master Slaie 1 L.-------------------------------------- >!L__--_-___J i

N 4

0 26

i Specific Description of the CRIS Monitor The In-Duct Monitor (IDM), model # DRMS-9115-SR, provides continuous monitoring of gases flowing through ducts or airways. This monitor incorporates spectral analysis to provide continuous quantitative and qualitative assessment of gamma emitting isotopes inside of ducts or air ways. The IDM is phy.acally mounted inside of the duct or airway to perform the required monitoring of the Unit 2 and Unit 3 Control Room Air at SONGS.

The IDM is comprised of the Monitor Assembly, which includes a detector in a capsule holder, coupled with an LPU. A junction box provides an interface between the LPU and the associated LDU.

The IDM Assembly utilizes a 1.25" X 1" scintillation detector mounted in an unshielded, aerodynamic capsule. The capsule is suspended by two arms and mounted to the duct or airway with a base bracket.

As the gas passes over the capsule, gamma emissions from the radioactive constituents of the gas are sensed by the scintillation detector. The signal cable for the detector is routed through one of the arms and exits the assembly at the base bracket. This type of monitor is teed for 2/3RE7824 and 2/3RE7825 Radiation Monitors.

The following diagram shows the logical configuration for the In-Duct Monitor:

i i

i l

Skid l

l Control Room l

i i

i i

i i

' 'su st2 ':

DAS-A I i e

sti + ; j 1

l Detector l

l i

i l

i mai. i.2s'a t")

ITO PC +-t-* Rs232 sL3

, D AS-B l l l

__, L P U l

i RDU i

l H acia, i

(sAsi e

ai Actuation l Ab"$2 8

i

+' s t2 l ll l

8 Legend l

i l

H Actuation l l i

l Anal Flc.,

j

sLI sL2 4

i l

LDU l

l r------------- 7 l l li

.s.us : i i

i 9 Recorder I i'

i H232g l

• To PC For Safety Related L_________________________l i_ _____'_= = = _= = = = _:

27

~. _

The DRMS to DAS Interface The DRMS to DAS Interface is designed to prevent the safety related DRMS from being interfered with,in any manner, by the non-safety related DAS This is achieved by a combination of hardware and software design features that provide defense in depth measures to prevent DAS interference with the mission of the safety related DRMS.

Physical Interface-Description The DAS interfaces with both the safety related and non-safety related DRMS through the RDUs (Remote Display Units) and through the LPU/IOs (Local Processing Unit / Input-Output Converters).

The DAS is connected to the RDUs through two RS485 buses, one for the Primary DAS and one for the Secondary DAS. These two buses are isolated from each other, so the failure of one bus does not affect the other bus. On each bus, the DAS is the master unit, and the RDUs and LPU/IOs are the slave units. It should be noted that the CPIS and CRIS monitors only use RDUs for DAS interface, so LPU/los will not be discussed.

The following diagram is the typical configuration of the RDU-DAS Bus:

v4 DAS **

1 f

Primary c

v4 DAS *

• 1 Secondory f c

1 q-I y

ASL2-SL3

' SL3 -

4 SL2 -

4 SL3 -

4 SL2 -

4 SL3-

+ SL2 -

4 4 SL2 -

4 SL3 -

4 ROU1 RDU2 ROU3 ROU4 RDU5 i

28

Functions of the RDU The safety barrier function of the RDU is designed to assure that within the constraints of its specification / qualification, the communication initiated by the non-safety related DAS will not impair the RDU's integrity or functionality. Furthermore, the DAS will not impair the integrity or functionality of any other safety-related device connected to the RDU.

Physical Interface-Signal Isolation Methods The RS485 signals from the seriallinks of the RDU are physically isolated from the rest of the RDU circuitry. The isolation for the RS485 signals is provided by two main componects: optocouplers and DC/DC converter. This assures that there is no continuity from the external signal into the isolated side of these devices and therefore into the rest of the RDU circuitry.

The RDU has three (3) identical RS485 serial links referred to as Serial Link B, C, and D. (Serial Link A of the DU is the RS232 serial link.) These three serial links are isolated from each other and from the RDU safety related circuitry.

The RS485 serial link signal from/to the DAS passes through optocouplers and a DC/DC converter located on the CRI board.

The following page contains a schematic which represents the typical isolation circu:try of the Serial Link D. In the schematic, the signal TXDD stands for Serial Link D Transmission, RXDD stands for Serial LINK D Reception, and E/RD stands for Serial Link D Chip Select.

The isolation for the signals TXDD, RXDD and E/RD is performed by 3 optocouplers: VP7, VP8 and VP9. They are Hewlett Packard components IICPL-2200.

The isolation for the +5V power supply is performed by a DC/DC converter: NR7. This component is a Newport component NME0505.

This design provides a complete physical isolation barrier (signals and power supply) between the

. internal circuitry of the RDU and the external serial link signals.

l l

29

e Software Provisions for the Safety Barrier 4

The combination of several defense in depth features in both the DAS and DRMS software prevents incorrect communication between the DRMS and DAS. First, the DAS does not contain the necessary communication driver function to write to the safety related DRMS. And the DAS is prevented from ever being so modified by administrative controls. The DAS can only read data from the safety related i

DRMS,it cannot write data.

Second, the safety related RDU contains a " logic switch". There is no structural or hardware difference between a safety barrier RDU and a non-safety barrier RDU. What distinguishes a safety barrier RDU is a software " logic switch" which is a flag set (parameter #19 of the DU parameter table).

When the software " logic switch" is activated (via the M ASS software on a portable maintenance computer), the RDU rejects all write command to change parameters received through either of its two (2) RS485 slave serial communication links. His rejection barrier is executed in the communication i

driver each time a frame is received. The configuration of the safety related RDU is assured by administrative controls.

Third, the communication protocol utilizes a Cyclic Redundancy Code (CRC) error checking to ensure j

that the request sent by the DAS is not somehow changed into a harmful instruction. Any message received by the RDU which does not meet the CRC error check is promptly ignored.

Fourth, sigtificant testing has been performed to verify the hardware and software perform correctly.

Examples of this are DAS continuous requests for data, fast electrical transient tests, and performance of DAS and DRMS Software Verification and Validation.

30

3.

Describe the manufacturer's recommendation for installation and use of this system, and how these recommendations have been incorporated.

The manufacturer provided recommendations for installation and use of the radiation monitors in a number of manuals and drawings for both the hardware and software. The installation recornmendations that were explicitly stated were contained for the most part in the installation manual. That manual describes the sequence of installation of the CPIS skid including inspections to be made, connection tubing and electrical wiring.

Other manuals provide a variety of recommendations and use information. A brief description of the information that pertains to installation and use recommendations in the documents is provided in the following list. Drawings are also included in the list since they provided information that is used by SCE for installation both mechanical and electrical.

System Level Digital Radiation Monitorirg System Overview Manual (General)

The manual provides a general overview of the Radiation Monitoring System, the Wireless Area Radiation Monitoring System, and the Data Acquisition System. The manufacturer provided additionalinformation and recommendations for each monitor through a series of appendices that contain a description of the monitor skid subassemblies and components, the configuration including channel and input / output definitions, operation of the skid, maintenance recommendations, calibration recommendations, troubleshooting, and related parts list and drawings.

User's Manual for MASS (General)

The MASS users manual provides a detail description of the Maintenance and Setup Software that enables the configuration and maintenance of the Digital Radiation Monitoring System equipment. The manualincludes recommendations for the configuration of the monitor parameters for various users of the MASS such as operator, maintenance, and supervisorlevels, it further provides detailed explanations of the parameters that may be used to configure the RMS equipment and in many cases includes default values. See the response to question 7 for additionalinformation.

Equipment Level (Skid, Control Room Panel)

DRMS 7804,7807 Layout (Containment Airborne Monitor)

DRMS 7824/7825 Control Room Airborne Monitor These vendor layout drawings provides the general information for the physical installation of the i

monitor skid. It includes the location, number and size of the attachment bolts; the clearances necessary to open enclosure doors; the location, size, and connection interface details for all sample lines in and out of the skid; the overall dimensions, center of gravity, and weight. This information is used to prepare construction work orders and instructions for installation.

DRMS Skid 7804,7807 P&lD (Containment Airborne Monitor)

The skid P&lD provides the size and interconnections on the monitor skid assembly. It includes information about the location of plumbing, instrumentation, and electrical connections as well as showing normal valve positions. This information is used to develop SCE specific maintenance procedures and to modify plant P&lDs to include the new monitors.

DRMS Skid 7804/7807 Power Distribution & Control Panel Electrical Schematic (Containment Airborne Monitor)

The schematic provides information regarding the intemal power, selector switch, and pump / motor control connections. These are used in construction for installation connections and maintenance for routine maintenance and troubleshooting.

DRMS Wiring Diagrams (Containment Airborne Monitor & Control Room Airborne Monitor)

The wiring diagrams show the interconnections between various subassemblies such as the 31

junction box and the power distribution & control panel and the modules (LDU, LPU, etc.).

Subassembly Level A series of documents has been provided by the vendor that provide additional detail at the subassembly level.

DRMS Power Distribution & Control Panel Layout These drawings provide the physical size and layout of the power distribution panels. It shows the placement of all the components such as relays, terminal blocks, hand switches, panel lamps, cable entry locations, wire ducts, etc. The information is used by construction during installation and pre-operational testing to identify the location of cable entries and components.

It is also used by maintenance in component replacement and troubleshooting.

DRMS Junction Box Layout This layout is similar to the Power & Control Panel Layout excupt ihe components are control components. Its used in the same way as the Power Distribution & Control Panel Layout.

DRMS Skid 7804/7807 Power Distribution and Control Panel Internal Wiring Diagram This drawing shows the intemal connections between components. It is used by construction and maintenance in the same way as the other layouts.

Installation instructions The vendor installation instructions provide information that is used by construction to install and check the monitor assemblies. The instructions include a list of reference documents, the tools that will be needed for installation, the inspection that should be performed, a list of precautions to be taken before installation begins, the sequence to follow for installation, and a final check test.

DRMS Technical Manual The technical manual provides information and recommendation for each monitor type. It includes a theory of operaticn, functional description, technical specifications, installation instructions, maintenance instructions, calibration procedures, parts list and drawing list. SCE uses the theory of operation, functional description, and technical specifications as part of training. Maintenance instructions are used as the basis for the maintenance performed on the monitors. Calibration procedures are discussed in the answer to question 5, but generally provide guidance in the preparation of SCE's calibration procedures.

User's Manual, LDU/RDU and LPU The user's manual for the DU and the manual for the LPU are used by maintenance for maintenance, replacement, and troubleshooting these type of modules. The manualincludes a detailed description of the equipment, installation and setting into service (used primarily after component replacement), LDUIRDU or LPU maintenance (both periodic and corrective), and technical characteristics.

SCE uses the recommendations in these and other manuals and drawings to create a Design Change Package (DCP). The DCP not only includes the manufacturers manuals and drawings but also the plant unique drawings that are standard within SCE. This is done to maintain consistency throughout the SONGS site. For example, manufacturer's wiring diagrams are translated into plant loop diagrams.

Manualinstructions are integrated into maintenance and operations procedures. Manufacturer's software configuration recommendations, calibration reports, functional test reports are used as a basis to produce a parameter set for each monitor.

l When the DCP is implemented, Nuclear Construction prepares documentation for the trades to install the l

equipment, make the mechanical and electrical connections, perform pre-operational testing and calibration of the monitor in accordance with the DCP requirements.

32 1

h 4.' Describe the planned post-installation testing.

The post-installation testing by Nuclear Construction is a prerequisite for Operations accepting the new digital radiation monitors as operational. Nuclear Construction utilizes existing station procedures as part of the normal post installation testing program in addition to any other special test (s) required by Section 7 Test Guidelines, of the Design Change Package for the DRMS. Listed below are some of the tests that will be performed priorto Operations acceptance of the monitors. Some of the test procedures have not been drafted at this time, therefore, the list below is the anticipated tests to be performed. The actual list may be slightly different.

Circuit integrity: A continuity and correctness check of the wiring.

Megger cables:. Insulation resistance check of wiring.

Hand switches: Verification of switch operation.

Relays: Verification of pickup and dropout voltages.

Light circuits: Verification of the operation of alllamps and acceptable uniform brightness.

Circuit breakers: Verification of circuit breaker ratings by test.

Thermal overloads: Test that they open as required.

Recorder Calibrate the chart recorders.

Pressure Switches: Calibrate the pressure switches.

Vacuum Switches: Calibrate the vacuum switches.

Containment Airbome Monitor Gas Detector: Isotopic Calibration Containment Airbome Monitor Particulate Detector: Isotopic Calibration Containment Airborne Monitor Channel Functional Test: A loop integrity test j.

Containment Airborne Monitor System Integrated Test:

f Gas Channel Testino l

Output Indication Verification Channel (N13/ Noble Gas) Conversion Factor Test Channel (N13/ Noble Gas) High Alarm Test Channel (MONITOR FLOW) Conversion Factor Test Channel (MONITOR FLOW) Low flow threshold Test Detector Fault Detection Check Test DAS ERDS & DAC Communication Test I

Pressure Switch Test i

Vacuum Switch Testing DAS Display Commands Testing LDU Command Test RDU Command Test Power Interruption Test Leak Test.

Report Generation 33 e

Loss of DAS Communication Test Channel Sample Flow Test

- Particulate Channel Testina

- Channel Beta Particulate (BetaPart) Test Channel Particulate Flow (PartFlow) Test Functional Testing Isotopic Testing Control Room Airbome Monitor in Duct Detector: Isotopic Calibration Control Room Airborne Monitor Channel Functional Test: A loop integrity test Cm. trol Room Airborne Monitor System Integrated Test:

Output Indication Verification Channel Conversion Factor Test Channel High Alarm Test Detector Fault Detection Check Test

- DAS ERDS & DAC Communication Test

' DAS Display Commands Testing i

LDU Command Test i

RDU Command Test I

Power Interruption Test Report Generation Loss of DAS Communication Test Service LeakTest on new welds.

I 34 a.

S.

Confirm that calibration procedures meet the technical specifications, applicable standards, and vendor recommendations.

Containment Airborne Radiation Monitor This confirms that the calibration procedures being used at San Onofre for the Containment Airborne Radiation Monitor meet the technical specifications and applicable standards. SCE has made some modifications in the vendor recommended calibration procedures. The following section describe the requirements and the methodology of SCE's procedures.

Technical Specification Technical Specification Surveillance Requirements (SR) 3.9.3.2, SR 3.3.8.4, SR 3.4.15.5, SR 3.4.15.6, and SR 3.4.15.7 require that channels be calibrated every 24 months. The Technical Specifications further require (SR 3.3.8.4) that the calibration be a complete check including the sensor to verify that the channel responds to a measured parameter within the necessary range and accuracy. The channel calibration leaves the channel adjusted to account for instrument drift between calibrations.

Measurement error determination, setpoint error determination, and calibration adjustment must be performed consistent with the plant specific setpoint analysis.

SCE has established a Repetitive Maintenance Order that requires that the Containment Airborne Monitor be calibrated every 24 months. The calibration procedures for gas and particulate channels have not been finalized and released at the writing of this response. SCE's procedures for the new digital radiation monitor are being written to perform a complete channel calibration from the sensor to the display. The calibration for the particulate channel includes an intensity linearity check using three sources of the same radionuclide and three sources using different energy radionuclides. The gas channelincludes a range accuracy check using two sources of different intensity each consisting of three radionuclides uniformly mixed together. The measurement error determination is based on the accuracy of the test instrumentation and the ability of technicians to adjust the parameters accurately. There are accuracy allowances included in the Analysis of Record for the Total Loop Uncertainty (TLU) and Setpoint determination based on experience at SCE performing similar adjustments. The setpoint determination error is also considered in the TLU. The calibration adjustment is performed in accordance with procedures that are consistent with the setpoint analysis. A value is available to the l

analyst for the AS FOUND and AS LEFT for various parameters from which drift can be established for a parameter between calibrations. Verification that the drift is statistically within the error value in the analysis can be performed when at least three calibrations have been completed.

Standards The standards that apply to the Containment Airbome Radiation Monitor are IEEE-2791971, RG-1.45, and RG-4.15.

IEEE-2791971 section 4.10 " Capability for Test and Calibration." Requires that a capability be provided for testing and calibrating channels and the devices used to derive the final system output signal from the various channel signals.

RG-1.45 section C8 'The leakage detection systems should be equipped with provisions to readily permit testing for operability and calibration during plant operation."

RG-4.15 section 6.1 "Radionuclide Reference Standards - Use for Calibration of Radiation Measurements Systems" Referenced in UFSAR section 11.5. Requires traceability of the of the sources used for calibration to NIST.

SCE's calibration procedures will meet these requirements.

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Vendor Recommendations i

The vendor has recommended that the monitors be calibrated at every refueling outage as a minimum.

When the calibration is performed the vendor has recommended procedures to be followed for each radiation monitoring channel and the mass flowmeter.

The vendor recommends that the N13/ Noble Gas Channel be given a temperature calibration, an energy calibration, a secondary calibration check, an intensity linearity check, and an intrinsic noise check. The temperature calibration is to verify that the temperature compensation subsystem for the detector channel is operating within an acceptable range and adjust it, if necessary. The energy calibration ensures that the location of a Cs-137 peak is correct and to adjust as necessary. The secondary calibration check uses NIST traceable sources to ensure that the detector subsystem efficiency is within the acceptable range and to adjust it as necessary. The intensity linearity check is used to ensure that the detector is within 10% of the average of three intensities of Cs-137. An intrinsic noise check is made j

to ensure that the intrinsic noise is below a pre-established count rate.

SCE's calibration procedures have used the vendors recommendations as the bases. SCE has included the vendor's recommendations except in areas where enhancements could be made. The temperature calibration and the energy calibration procedures are the same as the vendor's recommendation. The secondary calibration procedure is not performed as the vendor recommends. SCE has procured two murces with a mixture of Barium, Cobalt, and Cesium in a low intensity and high intensity to simulate the amber of gas. These are used in place of three Cs-137 sources. The intrinsic noise check is not performed. A systematic background check is performed and the background is recorded.

The vendor recommends that the Beta Particulate monitor be given a temperature calibration, an intrinsic noise check, a gamma compensation calibration, and an efficiency calibration check. The temperature calibration ensures that the temperature compensation for the detector is operating within an acceptable range and adjust it if necessary. The intrinsic noise check verifies that the intrinsic noise is below a pre-established count rate. The gamma compensation calibration determines the ratio to be used in the parameter set database to compensate for difference in performance of the beta / gamma detector and the gamma only detector for dynamic background subtract.

SCE's calibration procedures have used the vendors recommendations as the bases. SCE has included the vendor's recommendations except in areas where enhancements could be made. The temperature calibration and the gamma compensation calibration procedures are the same as the vendor's recommendation. The efficiency calibration procedure is not performed as the vendor recommends.

SCE has procured five sources using Chlorine, Strontium, and Technetium in a source holder that simulates the particulate filter. The Chlorine sources have three intensities. These are used in place of three Cl-36 sources recommended by the vendor. The intrinsic noise check is not performed.

The mass flow meter calibration is an accuracy calibration and a calculation of the parameter to be used in the flow meter algorithm parameter set. The vendor recommends using a rotameter as the standard by which to measure the sample flow rate and compare that with the displayed values.

SCE's calibration procedures follow the vendor's recommendation except that the SCE procedures utilize a ca!!brated flowmeter rather than a rotameter.

Control Room Airborne Radiation Monitor This confirms that the calibration procedures being used at San Onofre for the Control room Airbome Radiation Monitor meet the technical specifications and applicable standards. SCE has made some modifications in the vendor recommended calibration procedures. The following section describe the requirements and the n ethodology of SCE's procedures.

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Technical Standards Technical Specification SR 3.3.9.4 requires that channels be calibrated every 18 months. The Technical Specification further requires that the calibration be a complete check including the sensor to verify that the channel responds to a measured parameter within the necessary range and accuracy.

SCE has established a Repetitive Maintenance Order that requires that the Control Room Airborne Monitor be calibrated every 18 months. The calibration procedures for gas channel have not been finalized and released at the writing of this response. SCE's procedures for the new digital radiation monitor are being written to perform a complete channel calibration of the gas channel from the sensor to the display by the use of transfer calibration sources.

Standards The standards that apply to the Control Room Airborne Radiation Monitor are IEEE-2791971 and RG-4.15.

IEEE-2791971 section 4.10 " Capability for Test and Calibration." Requires that a capability be provided for testing and calibrating channels and the devices used to derive the final system output signal from the various channel signals.

RG-4.15 section 6.1 "Radionuclide Reference Standards - Use for Calibration of Radiation Measurements Systems" Referenced in UFSAR section 11.5. Requires traceability of the sources used for calibration to NIST.

SCE's calibration procedures will meet these requirements.

Vendor Recommendations The vendor has recommended that the monitors be calibrated at every refueling outage as a minimum.

When the calibration is performed the vendor has recommended procedures to be followed for each monitor for the radiation monitoring channel.

The vendor recommends that the In-Duct Monitor be given a temperature calibration, an energy calibration, a secondary calibration check, an intensity linearity check, and an intrinsic noise check. The temperature calibration is to verify that the temperature compensation subsystem for the detector channelis operating within acceptable range and adjust it, if necessary. The energy calibration ensures that the location of a Cs-137 peak is correct and to adjust as necessary if it is not. The secondary calibration check uses NIST traceable sources to ensure that the detector subsystem efficiency is within the acceptable range and to adjust it as necessary. The intensity linearity check is used to ensure that the detector is within 10% of the average of three intensities of Cs-137. An intrinsic noise check is made to ensure that the intrinsic noise is below a pre-established count rate.

SCE's calibration procedures have not been finalized at this writing but will meet the vendor's recommendation for temperature calibration, energy calibration, secondary calibration check, and intensity linearity check. Intrinsic noise check is not performed.

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6. Describe how repair of failed boards will be accomplished, i.e., on site or at the vendor.

SCE has contracted with the vendor, MGPI, to perform repair or replacement of failed components on the Digital Radiation Monitoring System. The system is comprised of discrete components such as the Local Processing Unit and the Remote Display Unit. Ghould one of these components fail, it is presently

' planned to remove the entire component and send it to the vendor for repair. Sufficient spares have been purchased to account for the repair cycle time. Safety related repair will be performed under the vendor's 10CFR50 Appendix B program.

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.-_____-__--_-_-___-________-___-___-____-___-_-__-_______-__1

7.

Identify what PCS, portable configurators, or other computer interface test equipment is used, and how that equipment is used and controlled.

The Digital Radiation Monitoring System (DRMS) uses a Portable Maintenance Computer (PMC) for testing, calibration, troubleshooting, configuration, maintenance, and data interrogation. The PMC is a portable notebook computer running a software module called Maintenance and Setup Software (MASS).

The PMC can be taken to the monitor and connected to an Display Unit (DU) through the RS-232 interface or directly to a Local Processing Unit (LPU) using an RS-232 to RS 485 converter. The MASS software can be used to perform the following functions at the monitor.

The primary functions of the MASS are to display the topology (all units found on the network during scanning), to report information on the units (alarms, status, measurements, etc.), to access the parameter setting boxes via the menus, and to execute commands. This is done through a windows based graphical interface including password protection at specific levels such as operator, mairMnance, supervisor, and manufacturer leve!s. The MASS can be used to load the monitor parameter sets.

The topology is displayed graphically to show the status of each DU, LPU, and measurement channel.

Each unit is represented in a normal mode, error made, alarm mode, or maintenance mode. The channels display the measurement value, the alarm threshold positions and a bar graph indicator.

Information reporting includes detail status reporting for the DU and LPU module as well as graphical functions for history and spectra displays. The mode that the DU and LPU use car, be normal operation; degraded mode; maintenance mode; bypass mode; alarm mode or operational hardware, software or system faults.

Events are stored in the LPU and DU and are accessible using the MASS. The list includes the date and time the event occurred and a description of the event. The event summary provides a history of the alarms, the faults that have occurred in the monitor, parameter faults that have occurred, and commands that have been issued such as placing the monitor in bypass.

The MASS also provides access to the configuration setting dialog boxes that allow authorized users to adjust the unit's parameters.

Each topic list on the left contains a parameter setting dialog box. The lists are slightly different for the DUs and LPUs. Some parameter sets that can be configured are shown in the following table.

Topic DU LPU Description Analog 1/O X

X This parameter setting box defines the analog output according to the current units, the variation between the analog input and output, and the type of display.

Buzzer Operation X

This box enables the parameter settings for the buzzer operating mode to be set in accordance with each alarm level and type of operation.

Indicator Light Operation X

This parameter. setting box enables the indicator light operating mode to be set in accordance with each alarm 39

Topic DU LPU Description LED and Relay Operation X

The operating mode of the 5 LEDs and the 5 relays that report LED information, can be specified using parameter setting box.

Network Parameters X

X The network parameters can be specified by using this configuration box.

Unit Parameters X

X The unit parameters are entered using this dialog box.

Configuration of the DU topology X

The DU topology (list of DU or LPU slaves) can be specified using this parameter box.

Configuration of the DU screens X

The display screens that will be available on the DU graphic screen can be selected with this parameter setting box.

Configuration of the operating X

X The DU temperature and intemal temperature and voltage voltage thresholds can be displayed using this parameter setting box.

Relay Command Mode X

The alarms that will activate the relays can be defined in this configuration box.

Setting Channel Parameters X

The parameters for active algorithms for each primary channel (1-4) and each extended channel (5-16) can be defined using this parameter setting box.

Parameters Specific to Each Detector X

This series of parameter setting dialog Type boxes allows tne configuration of the various detector types such as the PlPS/ particulate, the SAS N13/ Noble Gas detectors.

The MASS also allows interrogation of historical and spectral data stored on the monitor.

The use of the MASS software and the PMC is controlled by procedure. The MASS software is Verified and Validated in the same way that the monitor software was V&V'd, as provided by our previous transmittal. The version of the MASS software V&V'd and accepted is controlled in the Software Configuration Database. Each PMC has a unique identifier and the authorized version of the MASS software that is to be used with that PMC. Prior to each use of the PMC at the monitor the software that is authorized for that PMC is loaded into the PMC. The individual using the MASS is qualified to use the MASS and has been given a password that allows that person access at the operator, maintenance, supervisor, or manufacturers level.

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