how long do these go for ? new stuff u are lucky to get 3 years out of today's junk

As far as I know, my 1963 Powr/Bracket still has the original ballast and bulb. It was taken out of service in '04 or '05 and still works. A lot of older stuff just won't die! When I was a kid, it was rare to see a non working streetlight. Not like today.

I think that the length of time that a ballast survives not only depends on the quality of it, but also the fixture that it is housed in.  For example, I think the reason that NEMA head ballasts last so much longer than those in yardblasters is because NEMAs have larger ballast housings which don't cause the ballast to become seriously overheated.  My NEMA stays pretty cool after running for awhile, but my yardblaster gets BURNING hot.  I'm sure this has something to do with how long they last. 

Also think about the size of the ballast and the windings, If you look at the yardblaster. Most of them are 175 watt and the real NEMA has a 100 watt ballast and it is bigger and the windings are heavier duty. Of course many real NEMA's have 175watt also. Just the fact that the ballasts are larger, they are not over worked like the junk yardblasters.

My Pemco 100w Merc NEMA head w/Lexalite optics is date coded to early 1965, went into service in June of '65 here in PPL territory, and served faithfully on US Route 6 in Honesdale PA until it was decomissioned in 1987 after 22 years. I saved her from the scrapheap and installed her at my house where she has continued to run every night, tonight included. I'm looking at her now over my detached garage's door as I write this. In a few months she'll have her 44th birthday providing my favorite light. Not bad service! By the way, she has a Jefferson Electric ballast inside and the original red Ripley SunSwitch on top too, which is also a great, long service for a PE if I must say so myself. This fixture is DEAD quiet still, and runs cool, which leads me to believe she'll continue to light my yard for another 30 years. I'l leave her up until she can't do it anymore. Not to worry though, I have three more ex-PPL units that are eager to get to work! 

My OV-14B served nightly from '57 until it was retired from street lighting duty in '06. The huge original ballast and three capacitors still work quietly to this day. It's still pretty clean inside except for dirt and dust on the door. Maybe it'll last another 50 years? I wouldn't doubt it.

My OV-14B served nightly from '57 until it was retired from street lighting duty in '06. The huge original ballast and three capacitors still work quietly to this day. It's still pretty clean inside except for dirt and dust on the door. Maybe it'll last another 50 years? I wouldn't doubt it.

Same for mine on the same date and area and all that....one more thing, mine's cleaner than Dave's! 

My Westinghouse OV-15 served the Duquesne Light area from 1970 until 2000 but it still works to this very day. So it had 30 years of good service.

my old nema head that has the teardrop lens out front was dated arround early 60's and still is going strong newer bulb but still fires up every night i doubt the hps fixtures on the main street will even last that long . thx for sharing guys. mers diehard if they die