1. Risk Assessment for Accessory Qualifications Combining HV & EHV Accessory Qualifications Understanding the Risk side of the Risk / Benefit Caryn Riley, Josh Perkel, Ray Hill, and Nigel Hampton NEETRAC 1

2. Risk Assessment for Accessory Qualifications CABLE ACCESSORIES Qualification Landscape Numerous philosophies & standards may be used to qualify a Transmission Cable System JOINTTERMINATION IEC & AEIC IEEE 404IEEE 48 ICEA AEIC CABLE SYSTEM COMPONENT 2 IEC- HV & stress limited

3. Risk Assessment for Accessory Qualifications Segments of Type Tests Pre Tests Post Tests Load Cycles Number Temperature Time Window Environment Water Tests Pre Tests Load Cycles Number Temperature Time Window Environment Post Tests IEC & AEIC System Survival IEEE Component Survival Water Tests 3

4. Risk Assessment for Accessory Qualifications Different Load Cycles IEC 60840 AEIC/ICEA CS9 2 hr 20 IEEE 404 IEEE 48 6 hr 4 30

5. Risk Assessment for Accessory Qualifications Temperature Constraints ConstraintIECICEA IEEE 48 IEEE 404 Number of thermal cycles 2030 Max Cond Temp 95 – 100100 – 10595 - 105 Loc n Temp Measurement Hottest Point Mid way between accessories Cycle End Temp None5 C of Ambient Time in window Any 2 hours Hr 6 to Hr 8 Any 6 Heating Time 8 hours Undefined Cooling Time 16 hours Conduit PermitRequireNot Specified It is possible to determine a Time / Temperature Recipe that fulfils these requirement on the large loop required 5

6. Risk Assessment for Accessory Qualifications Thermal Profile Impact - AEIC AEIC 3000A 2 step 6

7. Risk Assessment for Accessory Qualifications Thermal Profile Impact – Combined Combined 4000A 4 - 5 step 7

8. Risk Assessment for Accessory Qualifications Exposure Considerations IEEE increases the number of cycles for a system Temperature and Voltage stresses are increased A complicated cycle increases the chance of a “missed” cycle – but the system experiences the ageing of the missed cycle 8

9. Risk Assessment for Accessory Qualifications Exposure Min Number of Cycles Reliability of Cycle Multiplier Cycles / Time (hrs) of Exposure On Test IEC / ICEA201.122 / 2 IEEE301.236 / 6 IEC / ICEA / IEEE301.339 / 6 IEC / ICEA then IEEE 20 30 1.1 1.2 22/2 58 36/6 9

10. Risk Assessment for Accessory Qualifications Test Architecture & Risk ConstraintIECICEA IEEE 48 IEEE 404 Min length cable20m+4m+ 12m+ Min no accessories1 of each type 2 Terms 4 Joints Component – IEC Test Established Designs Mean Incident Rate (%) Cable5 Joint40 Termination (incl GIS)15 10

11. Risk Assessment for Accessory Qualifications Impact of Architecture & Risk ABCD E Cable Section12-- 1 Termination222- 2 Joint12-4 4 11

12. Risk Assessment for Accessory Qualifications Conclusions Combined IEC & AEIC tests have become very standard Combined IEEE & IEC & AEIC tests are theoretically possible and theoretically have lower costs In recent years we have not found a scenario where the Benefits are commensurate with the increased Risk and difficulty of Recovery –Temperature control is difficult on the large loop required –Complex architecture increases the risk –Cycle Exposure is increased due to complex temperature cycle Collation of Type Test performance and Survivability Estimates certainly provide the vocabulary to improve Cable System Technologies 12