So the other day, I got bored and bought a 175-watt mercury vapor bulb. I have a Tesla coil that puts out around 200,000 volts and I wanted to see if I could get it to light like my fluorescent tubes do when I put them near the coil. Well, unfortunately, that didn't work, and all I got was some corona discharge inside the arc tube, even with the coil arcing to the bulb and the other end grounded.  So now I have a 175-watt mercury vapor bulb just sitting there (if you check my gallery, I have posted a picture of it). Now I'm a bit of an electrical junkie and I like to collect and display electrical stuff, while I don't have a lot right now I'm working on building my collection. I want to proudly display my mercury vapor bulb and be able to use it. I'm well aware of the ban on MV ballasts over a decade ago, although I've found some old ballasts on eBay that will work. I'll also need an E39 mogul base socket, preferably porcelain (which I'll probably need to order online as well since all the brick-and-mortar hardware stores/home improvement centers near me only sell the lame E26 medium base sockets). The ballast I'm looking at is an Advance 72C3084-NP001 and can be wired for 120 or 277 volts. It's described as an "F-can ballast" and resembles a typical fluorescent ballast, this will probably be the one I use mainly because it's potted so it will run quieter and all the components needed to start the lamp are contained within the ballast case, so wiring it should be quick and simple. I thought about maybe getting a project box, mounting the ballast inside, then installing the socket on the outside, however a couple things come to mind: I know ballasts, especially magnetic ones, get rather hot during operation, so I would probably need to use an aluminum box instead of the typical plastic or mount the ballast in such a manner that there's adequate airflow around all sides of the ballast. Additionally, the lamp itself will get very hot and I don't want it near anything that might melt/catch fire. Plus the ballast chassis needs to be grounded, so if I did use a box to house the ballast, aluminum would probably be the best option. HOWEVER, the more I think about it, I may want to display the ballast, too...so I could just mount the socket and ballast to a board and use a junction box to conceal the wiring, or just leave the wiring exposed (I'd be using snap-on wire nuts or WAGOS to make electrical connections). And this brings to mind another idea...since I'd be wiring the ballast for 120V, it would have an unused leg for 277V, so I could maybe wire a twist-lock outlet to the 277V leg for testing 277V lights, and fuse it so not to overload the ballast. These are just ideas I have at the moment and I've been thinking a LOT about it, I could try to draw some diagrams to give a better idea since I kind of rambled in my descriptions...although I'm sure some of you out there have made your own fixtures, so really I'm just looking for any input/ideas.

Again, I apologize for the rambling, but I've been losing sleep trying to think of what I can do!  What do you guys think? Does anyone have better ideas? As I said, I can try to draw some sketches of what I've been thinking, but I feel like my ideas are rather cheesy. Anything will be appreciated! Thanks, Jon

I generally build ballast boards like this although with the profusion of wires you get sticking out of the sort of ballasts you get over there, that might end up looking just a bit messy 

You could try an enclosure, but it would really need to be metal, one of our other British members makes some nice ones like these, although the boxes do tend to be rather expensive.

One idea could be to build a remote ballasted chandelier that uses multiple 175w H39 mercury vapor lamps in which the ballasts are housed in the attic.

F-can ballasts don't need to be enclosed. The f-can casing the ballasts are in are accepted by code as a enclosure. You will need to attach a junction box to the end with the wires though. Universal SB-4 or Advance PC-857 are the part numbers. These junction boxes are designed to clip to the side of the ballast where the wires emerge to enclose the splices. For mounting, F-can ballasts are designed to mount directly to a metallic surface (such as a luminaire frame when used with recessed lights) or spaced away from other surfaces using a spacer bracket. (Advance PKG-625, easily made at home with a vice and a drill drawing is in attached drawing).

I have the same Advance F-can 175w mercury ballast. I ended up turning it into a open ballast using a junction box I drilled a holes in for the wiring and mounting screws (use a grommet for the wire hole and deburr), a power cord, and a mogul lampholder. . See the attached picture.

A F-can ballast with the junction box and mounting hardware is also a code complaint method to remote ballast lights to convert them for HID use. The ballasts can be mounted in the attic or a electrical closet.

@joseph_125, I like your setup. By chance would you know the dimensions of the ballast case, also the distance between the mounting holes? It looks like the mounting bracket you specify is discontinued. So I may end up installing the ballast in a junction box or mounting it to a grounded surface then using a standard box (since the lampholder I'm using is a mogul base lampholder that mounts to a standard junction box). I already ordered the ballast, it should be delivered next week hopefully.

Thanks, you can find the dimensions of the ballast in this spec sheet . The 175w metal halide ballast has the same dimensions as the 175w mercury vapour unit. If there are any that are missing I can measure mine but I believe it should have the dimensions of all the mounting holes.

For grounding, mine is bolted to the junction box which itself connected to the ground wire from the incoming line cord. All the splices are enclosed in the junction box. There's no switch but I suppose it's easy to drill a 1/2" hole somewhere on the side of the box and install a small toggle switch.

If you have an empty streetlight shell laying around, you could use that as long as everything fits and has adequate ventilation