According to Jake :

Dope growing is something I've heard these things are used for.... my
brother's a police officer and has told me some of the stories on these
nutty hookups.

Out of curiousity, I did a few google searches.

H'm. At least some commercial grade grow lamps run at 480V.

See, for example, the GLX series of fixtures:

http://www.poly-tex.com/pages/accessories/lighting.html
--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.