kurt@fluke.UUCP (Kurt Guntheroth) (02/02/85)
Independent of the merits of so-called 'long life' bulbs, you should be
aware of the voltage rating of the bulbs you buy.
In the Pacific Northwest, our voltage runs pretty high; about 125 VAC. If
you look at 'bargain' light bulbs you find on special in stores, you usually
find they are rated 117 - 120 VAC. If your line voltage runs higher than
this, the bulbs will not last even their rated lifetime. I now pay a few
cents more and get bulbs rated at 125 or 130 VAC. I have not noticed any
decrease in light output (although I bet the difference is measurable).
What I have noticed is that since I started doing this, I am not changing
light bulbs very often, where before it was a weekly event that a bulb would
blow in some inconvenient fixture.
On the East coast, I think the line voltage is lower. Still, it would be
interesting to check. If you seem to always be changing bulbs, try a
higher-rated bulb.
--
Kurt Guntheroth
John Fluke Mfg. Co., Inc.
{uw-beaver,decvax!microsof,ucbvax!lbl-csam,allegra,ssc-vax}!fluke!kurtdms@fluke.UUCP (Dave Sherman) (02/04/85)
In this discussion of bulb life vs. voltage vs. cost vs. efficiency, etc., I haven't seen any mention of probably the longest life bulbs you can get, Traffic Signal bulbs. I get used Westinghouse 67 Watt bulbs rated 8000 hrs at 130 V from a friend who gets them from the Seattle Engineering department. They replace the bulbs after 5000 hours whether they are burned out or not. I've not had one of these burn out on me yet even though they are already well used. They are also mechanically rugged, and good for trouble-lites. The only problem is that they are not very bright (== not efficient). --- David
ron@brl-tgr.ARPA (Ron Natalie <ron>) (02/11/85)
Then there is always the principle of pre-heat current. That's where you keep a small flow of current through the bulb even when off to keep the filament from cooling down two much. The advantage is only realized in lamps that are turned on and off a lot. They filaments last longer and the bulbs come up to full brightness faster. -Ron