A while ago i bought a batch of NOS MV lamps from a local seller and it included a brand new GE 400w Mercury Vapour lamp however I do not have any gear to run it.

I was wondering if it would work decently on a 250w HM/MV ballast since I have 3 of those but I want to ensure that if ever I did do this, it wouldn't harm anything. Of course I have various 250w lamps of both MH/MV to use but seems such a shame to waste a good 400w MV lamp... Especially since it has such a beautiful red start up (tried briefly on a really old unlabelled ballast i thought was 400w but isn't)

You could but it'd be underdriven, which would cause premature electrode sputtering and shorter life. Your best bet is holding out for a 400e MV/MH ballast.

Check your local Craigslist for "Metal halide light fixtures". You should be able to find a 400w MH highbay or few for under $40.

I ended up getting 4 large canopy lights from a local seller for $60 that were 400w Mercury Vapour. In total there is 4 MV/MH 400w HPF ballasts and 4 used but working 400w MV lamps - All Sylvania.

The canopy lights have been stripped of their gear and lamps and are awaiting a decision on their fate. 3 of them are in decent shape and 4th with a cracked cover.
They are 2x2 ft size and have prismatic drop dish covers. The covers can actually fit in regular 2x2 troffers.

Pictures coming soon of these canopy lights.


I plan to use the ballast thats most quiet and keep the other 3 as spares, and I have 5 lamps total now, 1 brand new. The gear and lamps will go into my flood light thats rated for up to 400w.

If you're in Canada this is a good score. Few 400 MV canopy lights are left now in Canada at 2015. Where these installed in some church or really old warehouse?

I believe these were once installed at a gas station gas bar but guy i bought them from got them for his garage but realized they are way to big and bright for his use

The science of running HID lamps probably starts on paper with equations & measured or theorised specs. The problem arises when actually running with real life materials & conditions as economically and ergonomically as possible. So yes lighting is NOT an exact science since nothing can be precisely controlled, at least within 5% of given specs. I'm not surprised as trencheel303 states that electronic start & high frequency "does wonders for the electrodes" of SOX lamps. I'm guessing (and intrigued) if SOX-type lighting were invented in this century instead of the 1930s, we'd be running them w/electronic HF ballasts!

If the SOX would be invented only now, with all the other existing light sources, it would never make it to commercial production, beyond specialized lab use. They are simply way too expensive to make (even today there are no more than 2 major lamp makers; and even with those I'm not that sure it isn't just rebranding of a single source).

But without LPS we most likely won't have HPS either (sodium use as a primary radiation element), without HPS we would likely not have the CMH (ceramic burner technology) and maybe even not any MH (again using sodium), so who knows how the industry would evolve.

I have gotten surplus lamp fixtures from electrical contractors after they have replaced or upgraded a system.They often advertise in the local want ad magazines or you can call them and see what they have.I have fixtures that came from Grady-White Boats and Michlen tire-high bay MH fixtures.The Michlen ones are actually pretty new 450W PSMH.Use Venture bulbs in them-NICE!!!The Grady White fixtures are indoor remote ballast "shoe box" lights with remote ballast-used on their inspection floor.And a High bay probe start 400W MH.Got these for like around 40 bucks each-the shoe box and ballast was 20 bucks-400W probe start MH.