1. An overview of I&C Systems in APR 1400 Parvaiz Ahmed Khand December 28, 2007

2. Table of Contents  Introduction  Objective & scope of study  Classification of I&C systems in APR 1400  Reactor protection System  Further Work 2

3. Introduction  I&C systems are the heart of most industrial plant operations.  Digital I&C systems provide many improved and important technical advantages for maintaining a plant.  These systems are interconnected together to convey the flow of information amongst different components of the plant  These interconnection can cause a number of security problems such as:  Unauthorized access to information (Loss of confidentiality)  Interception and change of information, software, hardware, etc (Loss of integrity)  Block of transmission lines and/or shutdown of systems (Loss of availability)  Unauthorized intrusion in data communication system (Loss of reliability)  In order to maintain the security of these systems there is need to develop a deep understanding about these systems 3 Objective and Scope of study Understanding of NPP digital I&C systems in APR1400

4. Classification of I&C Systems in APR 1400 I&C Systems Safety Related Systems Systems required for safety Systems not required for safety Plant Protection System Reactor Trip System Systems required for safe Shutdown Safety related display instrumentation Shutdown cooling system suction line valve interlocks Safety injection tank isolation valve interlocks QIAS-N and IPS alarms Control Systems Qualified Indication and Alarm System Main Control Room facility Information Processing System Large display panel NSSS integrity monitoring system Communication equipment Data Communication System

5. Collection and display of plant data NPP processes Sensors and Transducers Remote multiplexers Control & Protection Systems Monitoring Systems Display devices and peripherals Data transfer betweenSourceIndependence and isolation Sensors and multiplexersHardwire Multiplexers and safety& control systemsDeterministic communication protocols IPS and monitoring/control/safety systems and signals DCN-IFibre optic cable and information gateway b/w DCN-1 and safety related systems QAIS-N and monitoring/control/safety systems and signals DCN-QFibre optic cable and information gateway b/w DCN-2 and safety related systems

6. Reactor Protection System TR: Sensors and transducers APC: Auxiliary Process Cabinet CPCS: Core Protection Calculator System BP: Bistable Processor LCL: Local Coincidence Logic RT: Reactor Trip ESF-CCS: Engineered Safety Features Component Control System OM: Operator Module ITP: Integrated Test Processor MTP: Maintenance and Test panel IPS: Information Processing system QIAS: Qualified Indication and Alarm System SIP: System Interface Processor AOO: Anticipated Operational Occurrences To other Channels From other channels Reactor Protection System (RPS) –To protect the core fuel design limits and RCS pressure boundary for AOO –Provide assistance in mitigating the consequences of accidents

7. TR: Sensors and transducers APC: Auxiliary Process Cabinet CPCS: Core Protection Calculator System BP: Bistable Processor LCL: Local Coincidence Logic RT: Reactor Trip ESF-CCS: Engineered Safety Features Component Control System OM: Operator Module ITP: Integrated Test Processor MTP: Maintenance and Test panel IPS: Information Processing system QIAS: Qualified Indication and Alarm System SIP: System Interface Processor To other Channels From other channels RPS Architecture Four redundant channels Hardware –Two redundant BP and four LCL processors does not perform multitasking –The PPS processor design integrates various system components, features, and functions into a microprocessor based unit. –The BP sends the bistable trip output signals to the associated cross channel communications. –Isolated fiber optic links transfer the bistable trip states to LCL processor in other channels. Software –Ensures predictable system performance and response under all conditions –Consists of Operating System (OS) and Application Software –OS Resides in non-violate memory of processor Consists of processor OS Performs I/O handling, Communication handling, Equipment self test –Application Software Resides in non-violate memory of processor separated from OS Implementation of specific code developed during PPS design process Consists of SW modules for Trip initiation function, Automatic function, and Status reporting function Interfaces operator interaction, alarm annunciation and manual and automatic testing Reactor Protection System

8. To other Channels From other channels System Interface processor (SIP) –Serve as data communication gateways to the IPS and/or the QIAS Selected PPS channel status Test results –Exchange information within a channel over a data communication network with: Bistable processor LCL processor PPS and CPCS OM MTP Reactor Protection System

9. To other Channels From other channels OM Located in Main Control Room (MCR) Used for: –Entering constants –Trip channel bypass –Operating bypass –Variable set point reset Shows indication of: – status of CPC/CEAC variables and calculations –Trip channel bypass –Operating bypass –Variable set point reset Reactor Protection System

10. To other Channels From other channels MTP Man-machine interface for testing Used for: – manual testing of bistable trip function –Trip channel bypass –Operating bypass –Variable set point reset Reactor Protection System

11. To other Channels From other channels ITP Used for: – manual and/or automatic surveillance testing based on user’s input via the MTP –PPS status monitoring –Shows LCL processor, SIP gateway, RTSS, ESF-CCC status indication Communicates with ESF-CCC trains via fiber optic cables Reactor Protection System

12. To other Channels From other channels Reactor Protection System Data transfer betweenSource BP and LCL processorHigh Speed Link (HSL) /(RS-422 serial data transmission link) PLC stations and a ChannelAdvant fieldbus 100 protocol ITP and PLC internal networkField bus protocol ITP and ESF-CCCHigh Speed Serial Link SIP and IPS/QIAS-NIEEE 802.3 10baseT Between segments in ESF-CCC (Group controller, Control channel gateways, division gateways, network bridge and MTP) ESF-CCS intra division communication network Group Controller and loop controller in ESF-CCSGroup network Segment in a ESF-CCS division and MTP & Soft controlIntra division communication network CPC and OMIntra system communication network CPCS and SIPFiber optic communication network

13. Further Study  Identification of systems that can be important for security  Security mechanisms in communication equipment  Access control systems  External Connectivity  Plant Local Area Network (LAN) architecture  Remote access/ 3 rd party access 13