automatice headlights

From about October to April I will probably be leaving my lights on all the time. During that time of the year at this latitude it is dark when I go to work and dark when I drive home. I have auto lights on my Ford and my old SAAB turned off the lights when you turned it off. During the summer I will probably not leave them on all the time. That when we get our long days.

 

Just a little off-topic, but plasma TVs don't have bulbs per-say, but they DO have a limited lifespan. They won't burn out, but they do get darker and darker as they age. Typically what I understand from manufacturers is a 4-5 year halflife if they're left on 24/7. Leaving videogame images frozen on the screen can seriously burn-in images too, which is bad.

Which is to say, if you leave the TV on all of the time, after 4 or 5 years, the picture will be half as bright as when you bought it. Of course most people don't leave their TVs on all the time, and will still be happy with the picture a decade later (probably long-after it's been replaced with something better anyway).

I went with a DLP ceiling-mounted video projector and it's beautiful, but has a similar issue with a 4000hr lamp life and around $300 to replace.

Dave

 

so twue!

vewwy, vewwy twue!
it's LCD displays that have tubes that can wear out or burn out. i've got a 50" Pioneer rear-projector TV that's 14.5 years old now, and have not noticed any dimming of the picture. my Viewsonic projector isn't used much (at least until i get my 7.1 surround system working in a few weeks, anyway, but the 3-400 $ lamp in THAT one is a bit intimidating. but even at 500 hours life, that's less than two dollars per movie, and that beats Blockbuster all hollow... and it gives me a 120" screen ten feet from my couch.

i'll take those tradeoffs any day!
[falk's first law...]

 

So very true. There have been many times when I could see the road just fine to drive and the lights don't seem to add anything but a car without it's lights on became visible much later than they should have for safety.

Which brings up a (probably) stupid question. Is there some circuit that chooses the power source for the 12V draws based on whether the ICE is running or do they always come from the 12V battery? I'm wondering because it seems to me that DRLs would drain the puny 12V more quickly and thus could force the ICE to run specifically to recharge it.

 

Bruce: The headlights run off of the 12-v. battery. That battery is charged via an inverter from the HV battery. The ICE charges that battery. So the ICE does not run specifically to charge the 12 v. battery. Since it does so indirectly via the HV battery, the amount of extra running time due to headlight use would be unnoticeable. The Prius does not even have a conventional alternator for the 12-v. system.

Alan: I have a ViewSonic PJ510. According to ViewSonic, the bulb should last 2,000 hours in normal mode, or twice that in "whisper-quiet" mode, which is not as bright, but might be adequate for some kinds of presentations. Watching one 2-hour movie a day, (in normal mode) that's about 3 years.

I hate driving at night because the on-coming headlights blind me. I suspect that many of them are misaligned.