Hey everyone!

This is Ryan, aka “MVMH 99” on Lighting Gallery.  I’m reaching out because I wanted to share something I thought you’d like to know.

Anyways, as we all sadly know, it is (apparently) true that the production of new mercury vapor fixtures and ballasts was banned as of 2008.  However, many on here may not know that one model of metal halide fixture made by Caster Lighting, but rebranded under other brands (most commonly Lithonia Lighting), actually contains what is nothing more than a typical 100W H38 MV ballast; the only difference is that they have an ignitor tap added.

To run them as MV fixtures, the conversion is extremely simple and fully reversible.  All you need to do is unscrew the inner reflector, untwist the wirenut securing the three white wires, and then disconnect and cap off the white wire going to the ignitor (small white box).  This will enable you to run MV bulbs without the risk of high voltage ignitor pulses damaging the lamp.  Also, despite being marketed as a 100W metal halide fixture, note a 100W bulb will NOT be overdriven.  This is because, as I mentioned, the ballast is really just a 100W H38 ballast modified to include an ignitor connection.

Here is the link to them on Amazon, for anyone interested:

https://www.amazon.com/Lithonia-Lighting-OFL-100M-BZM4/dp/B0026T3YDS/ref=sr_1_4?dchild=1&keywords=lithonia+100w+metal+halide&qid=1604789574&sr=8-4

The only challenge, though, is finding clear 100W MV bulbs.  There are some going for great prices on eBay right now, and I actually picked one up myself.  Here is the link to the bulbs:

https://www.ebay.com/itm/100W-120V-Mercury-Vapor-Light-Bulb-Lamp-Medium-Base/152244193723?hash=item23727609bb:g:2lUAAOSwmLlX2aS7
Get one while supplies last – it seems the 100W clear MV bulbs are EXTREMELY hard-to-find nowadays in wake of the transition to LED lighting.  Many manufacturers appear to have abandoned the production of clear ones, at least.  Only the deluxe white ones appear to be readily available on most sites.

I hope this message finds you welcome – I know many here want an MV fixture really bad, but either have trouble locating them or cannot afford them due to how absurdly overpriced they tend to be on online marketplaces.

You can probaly use 70w MH lamps in these fixtures?

You can probaly use 70w MH lamps in these fixtures?

I would certainly think so; to me, the 100W bulbs have always seem slightly underdriven on the included ballasts.  I think they are more 70W-suited for metal halide than 100W.