I was there when there was a (much bigger) quench during commissioning of the LHC [0][1]. It was also at the focusing quadrupole modules - maybe the same ones?

I could make a joke about how it's Fermilab's vengeance for not having their own accelerator, but that would be dishonest: these focusing modules are the most complex ones of the whole ring.

[0]http://stephatcern.blogspot.com/2008/12/photos-of-lhc-damage... [1]https://home.cern/news/press-release/cern/cern-releases-anal...