Why my Sylvania HSI-TD 70W/WDL have high dose of halides?

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Topic: Why my Sylvania HSI-TD 70W/WDL have high dose of halides? (Read 1531 times)

dor123
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I've noticed that my Sylvania HSI-TD 70W/WDL, have tons of liquid halides when hot, so much that the arc can't be seen well.
Why is this?

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I"m don't speak English well, and rely on online translating to write in this site.
Please forgive me if my choice of my words looks like offensive, while that isn't my intention.

I only working with the international date format (dd.mm.yyyy).

I lives in Israel, which is a 220-240V, 50hz country.

James
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Because the particular halides do not have high enough vapour pressure to attain the desired spectral performance at the available arc tube wall temperature. So more halide is added to raise the total vapour pressure, and improve performance.

It is maybe a rather old lamp, over time all manufacturers optimised their thermal designs to be able to reduce the salt dose. And in Sylvania’s case changed from dosing with pure mercury to 3% cadmium in mercury to improve colour rendering without need for halides.

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dor123
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@James: Here is the lamp: https://www.lighting-gallery.net/gallery/displayimage.php?pos=-246513

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