Topic:"Performance Monitoring" in M03715

NON-CONFIDENTIAL 1 Request IR-5: 2 3 In its approval request (page 4 of 20) NSPI states that since 2001 there have been four 4 transformer failures at Kempt Road: 5 6 (a) Please describe the findings of the investigations into the root cau...

AI summary NSPI's response to IR-5 explains that transformer failures at Kempt Road since 2001 were caused by through faults from distribution system interruptions (e.g., trees contacting lines). Corrective measures include setting reclosers to single-shot reclosing before wind events to prevent re-energizing circuits after faults.

NON-CONFIDENTIAL 1 Request IR-6: 2 3 On page 4 of 20, under "Why do this project", NSPI states: 4 5 6 7 8 It is expected that one of the three transformers that has not been removed from service to be rewound is at risk of failure due to t...

AI summary NSPI claims a transformer at Kempt Road substation is at high risk of failure due to past transformer faults and its 1976 installation date. The request (IR-6) asks for documentation supporting this claim, but NSPI states no documentation exists, relying instead on historical failure data and age.

IR-19: With reference to the response to IR-6: - a) Describe any test results regarding the integrity of this third transformer. - b) On page 4 of 20 of the submission NSPI states: liThe remaining unit has been exposed to similar condition...

AI summary IR-19 queries NSPI on test results for a third transformer's integrity, risk assessment of a unit post-procedure, reinforcement measures for transformer integrity, and cost comparison between enhancements and replacement.

IR-28: Please provide and discuss assumed transformers' failure rates, and probabilistic risk assessments of the reliability of power supply to customers in the downtown Halifax area, for the following transformer configurations at the Kem...

AI summary The document requests probabilistic risk assessments and failure rate analyses for transformer configurations at Kempt Road Substation across six timeframes, including pre-2009, post-2010, and scenarios with spare transformers. It also asks for economic analyses comparing urgent transformer purchase versus delayed purchase, referencing prior IR-5(b) responses.