IMIA WGP 110 (18) IMIA Working Group Paper WGP 110 (18) IMIA Conference Singapore, 1st-5th September 2018 ELECTRICAL FAILURES NOT RELATED TO WEATHER CONDITIONS Name Company Phone Country Mamoon Alyah (Chair) CEERISK Consulting +44 7495 737 005 United Kingdom Oliver Thoma Advanta Global +44 7921 948 771 United Kingdom Jeff Ashman Advanta Global +44 785 250 1074 United Kingdom Brendan Reed Codan +4530378434 Denmark Tom Kristiansen Codan +4530377695 Denmark Milind Bhatawadekar Bhatawadekar Loss Surveys +91 98200 72 988 India Michael Shehan Qatar General +974 6666 4293 Qatar Mike Robertson (Sponsor) Liberty Specialty +44 7799 894 308 United Kingdom Paul Lowrie Clyde & Co +44 7703 746 953 United Kingdom Simon Dejung Scor Global +41 44 639 97 34 Switzerland Ben Adams Charles Taylor +44 203 889 8232 UK 1 IMIA WGP 110 (18) Contents Executive Summary ................................................................................................................................. 4 Definitions ............................................................................................................................................... 5 Electrical System ..................................................................................................................................... 6 Generation .......................................................................................................................................... 6 Transmission ....................................................................................................................................... 6 Distribution ......................................................................................................................................... 7 Major Electrical Equipment .................................................................................................................... 7 Generators .......................................................................................................................................... 7 Transformers ....................................................................................................................................... 8 Generator Step Up Transformer ......................................................................................................... 8 Bushings .............................................................................................................................................. 9 Cables .................................................................................................................................................. 9 Switchgear ........................................................................................................................................... 9 Circuit Breakers ................................................................................................................................. 10 Bus Bars ............................................................................................................................................. 11 System controls ................................................................................................................................. 11 Electrical Protection systems ........................................................................................................ 11 Site Control and Data Acquisition Systems (SCADA)..................................................................... 11 Voltage Regulators ............................................................................................................................ 11 Shunt Capacitors ............................................................................................................................... 12 Air switches ....................................................................................................................................... 12 Surge Arrestors ................................................................................................................................. 12 Automatic Circuit Reclosers .............................................................................................................. 12 Coupling Capacitors .......................................................................................................................... 12 Coupling Capacitor Voltage Transformer.......................................................................................... 12 Types of Electrical Faults ....................................................................................................................... 12 Symmetrical faults ............................................................................................................................ 13 Unsymmetrical faults ........................................................................................................................ 13 Typical Causes of Electrical Faults ......................................................................................................... 14 Electrical Causes ................................................................................................................................ 14 Partial Discharge (PD) ................................................................................................................... 15 Line disturbance ............................................................................................................................ 15 Electrical Overloading ................................................................................................................... 15 Mechanical ........................................................................................................................................ 15 Abrasion ........................................................................................................................................ 15 2 IMIA WGP 110(18) Vibration ....................................................................................................................................... 16 Mechanical Impact ........................................................................................................................ 16 Environmental ................................................................................................................................... 16 Contamination .............................................................................................................................. 16 Moisture ingress ........................................................................................................................... 16 Heating .......................................................................................................................................... 16 Animals .......................................................................................................................................... 17 Ageing ........................................................................................................................................... 17 UV exposure .................................................................................................................................. 17 Defect ................................................................................................................................................ 17 Human factors ................................................................................................................................... 18 Misapplication ............................................................................................................................... 18 Poor manufacturing/poor workmanship ...................................................................................... 18 Inadequate maintenance .............................................................................................................. 18 Sabotage and malicious mischief .................................................................................................. 18 Preventing Electrical Faults ................................................................................................................... 18 Insurance Considerations ...................................................................................................................... 19 Cause and coverage .......................................................................................................................... 19 Recovery/Subrogation ...................................................................................................................... 20 Loss Examples ....................................................................................................................................... 21 Electrical Damage and Fire in TR ....................................................................................................... 21 Switchgear Fire .................................................................................................................................. 22 Literature review ................................................................................................................................... 23 References ............................................................................................................................................ 24 3 IMIA WGP 110 (18) Executive Summary Electrical system breakdowns are a leading