Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway 1 Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway Simon Hua

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway2 Introduction – Times of Austerity 2010/2011 – Signalling and power supply failures – 700,000 delay minutes – loss of: £21 million – 2019 – ORR has set a challenge to Network Rail to save £1 billion / year. How can Railway Signalling Power provide cost savings? By the use of Class II Cables and Equipment.

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway3 Content IT Earthing Systems Legacy IT Systems Application of EaWR 1989 Existing IT Systems Proposed IT Systems Summary

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway4 IT Earthing Systems

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway5 IT Earthing System – Single Line Diagram Back up supplies using: -Generator and/or -Uninterruptable Power Supplies (UPS).

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway6 IT Earthing System – High Impedance to Earth Isolation transformer at PSP provides high impedance between line conductors and earth – BS7671 Reg Typically: –400V/400V in former Southern Region. –400V/650V in former Western Region.

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway7 IT Earthing System – Touch Voltage Touch Voltage (U C ) compliance required under: Normal Conditions – U C ≤ Permanent Condition. 1 st PEFC – U C ≤ Permanent Condition. 2 nd PEFC ≤ Temporary or Short Time Conditions U C. Maximum U C – BS : R A x I d ≤ 50V. Leniency on Permanent U C – BS-EN Reg. 7.2: R A x I d ≤ 60V.

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway8 IT Earthing System – 1 st PEFC Event of a 1 st PEFC at the end of the FSP: U C = 1 st PEFC x R E where R = R E + R L2 + R Tx + R L1 + R Tx

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway9 IT Earthing System Characteristics PROS: –Survival of 1 st PEFC without disconnection of supply – High Availability Score. –Low 1 st PEFC equates to low fire risk – High Safety and Reliability Score. CONS: –U C reliant on earth electrode (R E ). –Low R E challenging to achieve & maintain. Variable with weather & ground conditions. –Compliant U C for is difficult to achieve.

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway10 Legacy IT System

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway11 Legacy IT System – What is Class I? Class I is: –Used for Legacy and Existing IT Systems. –Basic Protection against direct contact ONLY. –Form of equipment construction with basic layer of insulation against electric shock. –Exposed-conductive parts bonded via protective conductor. Therefore, provision for Fault Protection against indirect contact required by other means. Either Automatic Disconnection of Supply (ADS) or Double or Reinforced Insulation (Class II).

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway12 Legacy IT System Characteristics Adopted by British Rail and Railtrack until Accounts for circa. 90% of signalling power systems. Equipment: –Basic Insulation with Class I equipment. Cable: –Stranded copper or aluminium cores. –Single rubber or ethylene-propylene-rubber (EPR) sheath. –Troughing (with lids) or directly buried in the ground or laid at the trackside.

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway13 Legacy IT System – 2 nd PEFC Event of a 2 nd PEFC at the PSP: U C = 2 nd PEFC x R E where R = R L1 + R E2 + R EA + R E1

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway14 Legacy IT System – Non-compliance Issues Evolution of electrical standards creates non-compliances. Availability of supply imperative. Non-compliance issues: –No form of Fault Protection against indirect contact. –High R EA means Low 2 nd PEFC. –Automatic Disconnection of Supply (ADS) difficult in 0.04 seconds. BR924 high inrush transformers (15x – 20x or greater).

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway15 Application of EaWR

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway16 Application of EaWR 1989 Electricity at Work Regulation (EaWR) 1989 is supported by Health and Safety at Work Act Compliance with both is compulsory. EaWR 1989 advocates BS7671. EaWR 1989 key principles for an electrical installation: –fit for its intended operational function. –safe during normal operation when faults occur. Legacy IT Systems compliance issue – No fault protection.

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway17 Existing IT System

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway18 Existing IT System Characteristics Accounts for circa. 10% of signalling power systems. Key difference – Distribution of integral or separate 3 rd core as: –supplementary equipotential bond (SEB) prior to 1 st PEFC. –circuit protective conductor (CPC) after 1 st PEFC. Equipment: –Basic Insulation with Class I equipment.

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway19 Existing IT System Characteristics Cable: –Stranded copper or aluminium cores. –Insulated with cross-linked-polyethylene (XLPE). –Steel-wire-armoured (SWA). –Poly-vinyl chloride (PVC) sheath. –Troughing (with lids) only.

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway20 Existing IT System – 2 nd PEFC Event of a 2 nd PEFC at the PSP: U C = 2 nd PEFC x R E Z = R L1 + R CPC

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway21 Existing IT System – Compliant Solution… Compliant System as provision provided for fault protection: –EaWR 1989 key principles achieved. –CPC results in High 2 nd PEFC. –ADS achievable. U C for ‘Temporary Condition’ ADS time: –65V = 5 seconds. U C for ‘Short Time Conditions’ ADS times: –650V = 0.2 seconds (approx.) –400V = 0.3 to 0.4 seconds (approx.)

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway22 Existing IT System – … At a Cost. However, arguably: Low Availability Score – Provision of ADS. Low Maintainability Score – Additional assets to maintain (CPC, SWA, EPR, IMD). Low Safety Score – Susceptible non-compliant U C (deteriorating equipment conditions) & exportation of faults.

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway23 EPRs/Programmable MCCBs and IMDs Electronic Protection Relay (EPR) and Programmable Moulded Case Circuit Breakers (MCCB): –Programmable I-t curves means faster ADS times. –Negates U C calculation. Design cost savings. –Cable CSA reduction by up to 70% (120mm 2 to 35mm 2 ). Cable cost savings. –Simplifies installation. Insulation Monitoring Devices (IMD): –Cable insulation will deteriorate over 35 year service life. –Monitors cable insulation for 1 st PEFCs. –Alerts and alarms are issued in the reduced operation and imminent failure. –Requirement of BS7671 Reg

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway24 Proposed IT System

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway25 Proposed IT System – What is Class II? Class II is: –Basic Protection against direct contact. –Fault Protection against indirect contact. –Form of equipment construction provides safety by design. –Basic and supplementary layer of insulation against electric shock. –No electrical requirements to bond exposed metallic parts.

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway26 Proposed IT System Characteristics Typically used as a final circuit: Innovative railway solution with distribution of Class II. Key Principles of Proposed IT System: –All equipment enclosures and cables meet Class II. –Compliant with BS7671 Section 412. –U C ≤ 60V.

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway27 Event of a 2 nd PEFC at the PSP: U C = 2 nd PEFC x R E where R = R L1 + R E2 + R EA + R E1 Proposed IT System – 2 nd PEFC

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway28 Proposed IT System Fault Protection (2 nd PEFC) To adhere to EaWR 1989 key principles for an electrical installation: –fit for its intended operational function. –safe during normal operation when faults occur. ‘Risk of single insulation failure and to a greater extent double insulation failure on a different conductor reduced by construction (intrinsic Class II design) to ALARP.’

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway29 Proposed IT System Benefits Class II benefits include: High Reliability (and Safety) Score – Low 2 nd PEFC equates to low fire risk. High Availability Score – no ADS provision. High Maintainability Score – Fewer assets to maintain. High Safety Score – No exportation of faults.

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway30 Proposed IT System Cable Characteristics Enhanced Unarmoured Cable: –Internal identification tape. –Rodent protection. –Low fire affected smoke & corrosive gas emission. –XLPE insulation. –PVC sheath. –Both insulation and sheath are up to 2.1 times BS7889:1997 results in stronger than SWA cable.

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway31 Proposed IT System Standards Key Class II Standard – NR/L2/ELP/27410 Issue 1. Applicable to: –Class II Cables – NR/L2/ELP/27408 Issue 1. –Class II Switchgears Assembly – NR/L2/ELP/27409 Issue 1. –Class II Transformers – NR/L2/SIG/30007 Issue 2.

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway32 Economical Benefits

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway33 Economical Benefits of Class II Performance of Proposed IT System to reduce train delay minutes due to Improved Availability. Cable costs savings: –35% 3 rd core CPC. –26% SWA. –67 Type A projects ( ). –Increasing cost of copper (5x over last 13 years). £26 Million

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway34 Economical Benefits of Class II Copper theft reduction with removal of CPC. –Cost to railways over last 3 years: –16,000 train delay minutes. –Increasing problem – 8 cable thefts a day. –Less incentive. Also: Reduced maintenance with fewer assets. Reduced design complexity. £43 Million

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway35 Summary

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway36 Summary – PRAMS Score IT System Performance Reliability Availability Maintainability Safety Legacy Existing Proposed Scores are rated out of 3. Performance scores taken as an average of RAMS scores.

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway37 Thanks to… Ron Checkman – Network Rail, Richard Allen – Network Rail, Tahir Ayub – Network Rail, Andrew Button – Network Rail, Richard Dunsford – Network Rail, John Alexander – Network Rail, Graeme Christmas – Network Rail, Pete Duggan – Invensys, Mark O’Neill – Atkins.

Date Railway Signalling Power – Economic and Performance Enhancements for Tomorrow’s Railway38 Any further questions?