8mm Forum: Euming 807 D question lamp

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Posted by Jorge Rondao (Member # 1434) on October 09, 2010, 07:00 PM:

Can I use a lamp 12v 100w in a projector Euming 807D without problems to burn anything, or due to the limit of projector 145W, can only use the 75W?
Regards

Posted by Steve Klare (Member # 12) on October 09, 2010, 09:00 PM:

Hello Jorge,

The thing to do is locate the code for the lamp the projector is designed for: either on the machine, or on the existing lamp or in the manual.

Apparently the 807D takes either the EFN (12V, 75W) or the EFP (12V,100W) so from the 'net it's impossible to figure out which one yours takes. From what I am seeing one would fit where the other fits. The safe bet is the EFN, but the EFP will put up a little brighter picture. It's probably OK to put in an EFP in a machine meant for an EFN, but unfortunately once you overheat the transformer because the windings weren't heavy enough or blow the lamp because there wasn't enough cooling air it's too late to say "maybe not".

Posted by frank arnstein (Member # 330) on October 10, 2010, 06:41 AM:

On the back of the projector is a small ID plate which shows the lamp specs. It will say either 12v 100w or 12v 75w on the plate. Use what is the right one for the 807d machine you have.

This is what I found when I tried messing around with Eumig 807d projectors & their different lamps.
If you put a 100w lamp in place of the correct 75w lamp it will still work but be much dimmer than usual & be dissappointing.
If you put a 75w lamp in place of the 100w correct one, it will be very bright but will blow the lamp filament very quickly.

So refer to the plate & use exactly whats stated there.

Posted by Steve Klare (Member # 12) on October 10, 2010, 01:14 PM:

Frank,

Are you sure you don't have your "75"s and your "100"s reversed there?

Posted by Jorge Rondao (Member # 1434) on October 10, 2010, 03:22 PM:

Thanks Frank, well my doubts is was even though the manual says to use 75W, wanted a bit more brightness, but I also thought he lost in the power and force it to dimmer.
It is best not to change and maintain 75W.
Thanks all
Regards

Posted by frank arnstein (Member # 330) on October 10, 2010, 03:47 PM:

Hi Steve
I am trying to recall the results of the Eumig 807d lamp swap test. It was done some months ago & perhaps I have quoted it the wrong way around. I arent quite sure now but I think it was a dimmer light when using the 100w lamp in place of the 75w one.
The important point I make is that its best to use the correct lamp thats listed on the ID plate.
dogtor

Posted by Steve Klare (Member # 12) on October 10, 2010, 05:03 PM:

We agree: the right lamp in the right place.

Here's how I see it.

A 12V, 75W lamp will produce 75W of light (and mostly heat) in a 12V socket.

A 12V, 100W lamp will produce 100W of light (and mostly heat) in a 12V socket.

A 12V, 75W lamp in a projector designed for a 12V, 100W lamp will have more than sufficient cooling but will seem relatively dim. The extra cooling will give a longer life than what it would have in a 75W max. machine.

A 12V, 100W lamp in a projector designed for a 12V, 75W lamp will (or may) have less than sufficient cooling but will seem relatively bright. (-maybe very briefly)

There's also the thing of can the lamp circuit in the 75W projector deliver 100/75 times as much current and last a long time(....maybe.) If the 100W bulb is really dimming it means that circuit is loading down and a lot of extra power is being radiated there as heat: watch out!

Like the question "How much does it hurt to whack my forehead with a mallet?", this question is probably best left unanswered.

Posted by David Donaldson (Member # 3858) on March 25, 2017, 07:15 AM:

It is mysterious about the 75w and the 100w. Is there a difference in models within 807D that requires this difference in lamps? Did it begin with exports to different countries? Or change during the production life?
Don's Bulbs lists both kinds of lamps for 807D but does not point to an equipment difference. How European of Eumig to cause such differences for no good apparent reason.

Posted by Brian Fretwell (Member # 4302) on March 25, 2017, 08:30 AM:

The reason a 100w lamp in a 75 w model could be dimmer is that the transformer core could be magnetically saturated and not transfer the amount of power needed. Early remote controlled theatrical dimmers were "Saturated reactor" ones that worked on this principle a remote current through a separate winding produced the effect.

Posted by Maurice Leakey (Member # 916) on March 25, 2017, 12:54 PM:

I bought a new Eumig 807D in the 70s because with its 75 watt lamp it was cheaper than the 810D. I used it for many years, often in church halls, etc., and never had cause to think the lamp was inadequate.
The dealer said "don't put a 100 watt lamp in it" and I always took his advice.

Posted by Will Trenfield (Member # 5321) on March 25, 2017, 09:07 PM:

Putting in a 100 watt bulb in a projector designed for a 75 watt one would lead to increased load on the transformer for which it might not be designed. Unless you like the smell of burning, don't do it.

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