We were cleaning out the shop in my Construction class and they somehow found their way into the shop... three out of six were left. from 10/2000, original case and all. I tested them on a 175W MV ballast but only one started up. Odd how some MH lamps will strike on MV ballasts but other lamps from the very same batch won't...
I have a 175w clear GE Multi-vapor with the GENERAL(GE)ELECTRIC etch that came out of a school gymnasium and was used and fired right up on a HX 175w MV ballast in my Electripak yardblaster (After I'd already had the thing for like 3 or 4 years I finally figured out what it was and decided to test it...originally it was just "A really big light bulb" and I thought it was HPS!
BUT the OCV on a 175w MV ballast is lower, so...that might explain why.
Yeah the lower OCV is why the lamps struggle to start on MV ballasts. Sometimes if you leave the light on for a half hour so so the MH lamp will finally start after a high enough charge has built up. That's what happened with the one Mh lamp that worked on the M-250R1. The first time it started right up but a few hours later when i lit it again one electrode glowed blue and it stayed that way so I left it and eventually after 15 minutes or so it began flashing every-now-and-then and by 20-30 minutes it finally struck and warmed up. They give off a really halogen-like glow, which I find to be common with Sylvania Mh lamp when they're new. Then they switch to a more blueish white almost like a new clear MV lamp but with much better CRI.
All the newish MH lamps I see have a slightly halogen-like yellowish-greenish-orangish color...older ones can be whiter or greened out...and when you see a pink one that's flickering and swirling get ready for a BANG!
I've always wanted to witness one of those things go out with a BANG! myself but never have...however I've seen some pretty fantastic incandescent failures!
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BUT the OCV on a 175w MV ballast is lower, so...that might explain why.