8mm Forum: causes of a blown lamp

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Posted by Tassos Laudas (Member # 588) on March 03, 2007, 05:21 AM:

Hi to all, i'd really appreciate knowing your opinion about which could be the cause of projector lamps getting easily blown, taking for granted that the voltage setting as well as the lamp itself are the correct ones!

Posted by Kevin Faulkner (Member # 6) on March 03, 2007, 05:26 AM:

You dont say what machine the lamp is in but from my experience lamps going brown is very often caused by lack of air flow across the lamp when the machine is running.

The lamps with integral dichroic mirrors also tend to show blistering of the coating round the base of the lamp again due to lack of air flow.

Some machines are more prone to this than others due to their design.

Kev.

Posted by Osi Osgood (Member # 424) on March 03, 2007, 02:42 PM:

I have an intersting lamp story. I was recently trying to put a new lamp in and it wasn't fitting well on plug-in,

(I'll call it that),

I had it half on, and it wasn't going on the rest of the way, so I attempted to take it off and try again. The
actual "hood" of the lamp,

(I'll call it a hood)

CAME OFF, completely. I was mortified. These things aren't cheap! I thought, what the hell, i pushed the bottom half of the lamp all the way on, and then fitted the "hood" back on.

It works fine! It hasn't worn out yet and I've had it on for at least 20 hours now.

Posted by Tassos Laudas (Member # 588) on March 03, 2007, 02:58 PM:

Osi when those things happen you leave them as they are as long as they work. Kevin i am refering to a Bauer t510 super 8 projector, and i was just curious wether this could have something to do with a worn tranformer. The lamp won't last more than 8 hours of projection...

Posted by Joerg Niggemann (Member # 611) on March 03, 2007, 05:13 PM:

Did you measure the lamp voltage? 5% increased voltage means 50% decreased life of your lamp...

I had a similar problem with a Bauer machine. Although the mains voltage setting was ok, the lamp voltage was too high.

Posted by Kevin Faulkner (Member # 6) on March 03, 2007, 06:29 PM:

Yes I would agree with that too. Have you checked the voltage at the lamp when it is on. I too suspect the voltage is possibly a little too high.

What is the voltage in your country and did it come from a country with a lower voltage. If we get a machine from Europe it will be set for 220V and if that is not changed and run on our voltage of 240v here in the UK the lamp life is really short.

Kev.

Kev.

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