LinearSLI-H wrote:GE say that discharge lamps need at least a 10 hour run on each switch on, less than 10 hours reduces life by 25% for each burning cycle.
Having said that, I don`t think it will harm fluorescents with just a half an hour run per start, and with the use of electronic starters to `soft start` any tube, I reckon you will still get a good life from them.
Ten hours a time seems wholly impractical, when you say "discharge lamps" do they include fluorescents in that, or do they mean it to be HID and similar? Many offices won't even run for 10 hours a time, and it's worse in places where they're on PIR switches to go off after a predetermined length of time. The college I went to in 2007 had lamps on PIRs, so I know that's been around for a bit.
MFL wrote:Fluorescent lamp life decreases with switching cycles. The standard 3h switching cycles are 2h45 on, 15 min. off to achieve the expected life of 10000h to 15000h. According to Sylvania technical data, lamp life is reduce to 50% with 3 time more switching cycles per day (30 vs 10 switching cycles/day). I found on a belgian website that fluorescent lamp life is only 4000h to 6000h with 6 minutes switching cycles versus 12000h to 15000h with 3h switching cycles.
The storage time doesn't affect lamp life as far as I know
The starter type affects lamp life as well. Sure, if you're frequently starting and stopping a 20W T12
on an FS2 I'd expect it to die quicker, especially given T12s often don't live as long as T8s and FS2 starters can be quite lively, particularly Philips S2 which in my experience are epilepsy inducers. I am told however that lamp life can be transformed with good quality electronic starters, most noticeable over short run times where they're much friendlier to the cathodes. You also have to consider electronic soft-start with modern T8s that last an eternity; where it isn't uncommon to see lamps run and run until they're merc starved, or just plain outlasting the control gear.
I have a 2x18W setup which generally gets started 2-3x a day, but only runs during the period where I need to prepare food or wash up. It's also the kind of application where when I want the light I want it NOW, so in this particular case I can't be arsed with a lazy starter, and so the 2x ultra fast electronic starters I have in there fit the bill perfectly. Now, a "dyed in the wool" collector might say it's completely the wrong application for fluorescent... but I like it. The light comes nearly instantly on and after a year of operation like this there is absolutely no sign of wear on the tubes. Such infrequent use, even despite frequent starts, obviously works in favour of overall lamp longevity, and I honestly wouldn't be surprised if my next relamp is when I'm much older! (very quick and dirty math: 15000 hours [or more, since modern T8s last nearly forever] divided by 730 [two hours runtime per day average, over a year] = just over 20 years).
One of the reasons I'm not at all afraid of using fluorescent lamps as a collector, is I reckon my odds of accidentally breaking a lamp are probably higher than it wearing out through occasional use.