David Wang and I did the service cap inspection in target hall: see WP I2015-10-06-10.<br>
Signs of sparking were seen underneath 3 insulators: E ("Cavity"), A ("Oven+") and B ("Oven -") at the pair water lines coming out of the feed-through and going to the HV chase. Specifically one water line of E is very close to the feed-through insulator (2-3mm gap) and here the sparking sings are more prominent: see picture. |