Refer to below question which was moved to DIY by moderators.
Electrical Engineering goes much beyond 24V and electronics. Lighting & power are a big and integral part of Electrical Engineering! In fact, the tags "HID" is already existing in electronics.stackexchange.com
And here are a number of similar posts accross electronics.stackexchange.com:
I took care for the original question to cover the broad scope of electrical engineering as the same question/answers would be relevant to others (although in the end I was looking for that answer for a "home improvement". Still, beeing myself an Electrical P.Eng. In my professional work, I have been dealing in a few cases of HPS lighting where I did not find answers to the same questions and would have like to stumble on the answer to the actual post.
I don't think that only for the fact that the actual end-application for the answer is indeed a DIY that the actual question must be posted in DIY. The material and content itself should be the relevant deciding factor to post and keep the question/answer.