Transformer fire at Cattenom nuclear plant during re-energization
Photo: Yoshieslunchbox, CC BY-SA 4.0, via Wikimedia Commons
A fire started on the Unit 3 station service (auxiliary) transformer at EDF's Cattenom plant while it was being re-energized during a maintenance outage; the automatic fire protection stopped it before firefighters arrived, and EDF reported no safety, staff or environmental impact. Putting a transformer back into service after an outage is a known high-risk moment, so underwriters should ask how energization is controlled and tested, and whether deluge protection is proven, not just installed. Source: EDF.