# Tungsten light lamp vs HID?



## picard (Jul 31, 2005)

Is the lamp for light house made of tungsten? Does this mean it is tungsten lamp instead of HID lamp? I saw the discovery channel program called "How it is made" which showed tungsten lamp manufactuered under 5 ATM pressure. Wow. That is a huge pressure. The gas was injected into the lamp under liquid hydrogen to prevent bulb from exploding.

My question: does the tungsten lamp produce a definite yellow color instead of white? Is this color suppose to penetrate fog better to guide ships to safe harbor? this is just curious question. Don't flame me ok /ubbthreads/images/graemlins/grin.gif


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## winny (Aug 22, 2005)

It would be a bad idea to use a tungsten lamp for a light house. Certainly it would be possible to use tungsten, but electricity costs, maintenance costs for replacing the lamp and the heat that needs to be taken care of would be big problems.
Although I have never been in a light house, I very much doubt that it would be equipped with anything other then HID. Probably mercury vapor or metal halide.

If you want to penetrate fog you better use low pressure sodium lamps. They are used at harbors for that reason and for their superior efficiency. Don't ask me why orange-yellow light penetrate fog better, it said so in the Philips brochure.


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## pyro (Aug 22, 2005)

Most of them are tungsten lamps, (usually only up to 2000W )
only the newer/modernised ones use HID.

The limiting factor isn´t thoe power of the light source, 
but the height of the tower, because the earth´s radius.


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