[Jim Story]

What does the bulb do 1000 hours?

I read that there could be risk of some damage.

Or does the light just fade?

Thanks.


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Jim Story

Live long and Prosper

 

[jmrobbins]

I don't know about that projector but most of the projectors we have at work will indicate when the time is up and after 50 more hours, will not turn on.


There is some info on metal halite lamps at this site: http://www1.ushio.co.jp/catalog/100e/1035.html


It appears that most of these Metal Halite lamps are considered at the end of their life when they produce less than 70% of the output rated or they just fail to ignite. It doesn't mention explosion.


[This message has been edited by jmrobbins (edited 07-24-2001).]

 

[Jim Story]

Thanks for that info and web site, which begs the question:

How to reset the time, so the projector will not auto-turn off, just to see how long that bulb will last?


------------------

Jim Story

Live long and Prosper

 

[watchformore]

Check out NEC's web site for the PDF version of the LT150 user's manual.
http://www.nectech.com/presentationp...ser_manual.pdf


It describes how the projector behaves when the lamp reaches 1000 hours and the auto shut-off 'feature' at 1100 hours. It also tells how to reset the timer.


The manual does mention the possibility of the lamp shattering, but the only caution is about being careful when cleaning up the glass.


-- Greg

 

[catullus]

Actually, the Dell honchos who have let their customers suffer so much confusion over this LT150 "dream-sale" should all be gathered together, dressed in body armor except for their butts, then experience the simultaneous explosion of all the 150 bulbs in existence.


Mike

 

[Kjelt]

The bulb should NEVER explode. If it does there is has been overheating of some kind or a manufacturer fault. In any case it is difficult to check how long a lamp will last. New lamps get a estimated lifetime from the manufacturer they can guarantee. Interesting is that many lamps prove to live much longer then expected, and the guarantee from the manufacturer will go up as the lamps are being used. So it is possible that a new projector will guarantee 1000 hours on a lamp and then refuse to use it while the same projector lamp 2 years later will be guaranteed at 1500 or even 2000 hours. Problem is that the projectorhardware will refuse to use the lamp since it is over the guaranteed lifetime. Every projectormanufacturer has it's own solutions. Some have a small memorychip in the lampassembly which tracks lamptime others do it in the projector and check if the lamp has not been removed. I even saw a projector where a lamp had some kind of fuse which was burned the second the projector was put on, when you removed that lamp and put it in again it would not be accepted by the projector's hardware even if it only had burned for a couple of minutes..... Correct me if I am wrong but in theory you can enjoy your lamp as long as you can stand for the lightoutput which will go down as time expires... you just need to know how to "fool" the hardware in thinking there is a new lamp inserted....


Kjelt

 

[Jonmx]

Lamp degrade over time, and a lamp failure is defined as reaching some level of output, I've seen 50% used. Of course all lamps won't degrade exactly the same so there is some sort of normal distribution. But if they guarentee 1000 hours, that probably means that more than 90% of the lamps will have more than 50% of light output after 1000 hours. You could probably expect to use it another 200-500 hours before you actually had a hard failure where you had no light output. I saw dell is selling the bulbs for only $459. I think I will buy a new projector at that price.

 

[Jim Story]

On pg 7 of the LT150 Users Manual (see web address in above message), it does say

"THE LAMP BULB MAY SHATTER" (if used beyond the 1000 hours).

Anyone have more info on this shatter mechanism?

Thanks.


------------------

Jim Story

Live long and Prosper