Author Topic: How MH lamps can make 3000K color with Na-Sc?  (Read 845 times)
dor123
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How MH lamps can make 3000K color with Na-Sc? « on: August 05, 2024, 02:55:50 PM » Author: dor123
I've a Sylvania HSI-TD 70W/WDL, which have 3000K color, have Na-Sc chemistry.
The American manufacturers used Eu:YPV phosphor coating to lower the CCT of their probe-start Na-Sc MH lamps to 3200K. But my lamp don't have any phosphor coating. Only Na-Sc halides.
How it is possible to make 3000K color with Na-Sc?
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Re: How MH lamps can make 3000K color with Na-Sc? « Reply #1 on: August 05, 2024, 04:34:23 PM » Author: LightBulbFun
I would guess at a basic level they just tweak the Sodium dosage ratio to get the colour temperature to the point they want?


for example my 1650W Venture M112 metal halide lamp which is quite highly dosed in sodium due to its high power loading and special nature is a 3200K lamp

https://www.lighting-gallery.net/gallery/displayimage.php?pos=-237831

https://www.lighting-gallery.net/gallery/displayimage.php?pos=-237874
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RRK
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Re: How MH lamps can make 3000K color with Na-Sc? « Reply #2 on: August 05, 2024, 10:46:33 PM » Author: RRK
In any way, to get lower color temp, more sodium have to be added and burner temperature have to be increased to increase partial sodium vapour pressure. Also, often some lithium is added. Phosphor coating is not much of help, notably adds to lamp costs, and also MH burners, unlike well made mercury ones, blacken quickly, and blackening will rapidly cut off UV available to phosphor, so color drift will be apparent.
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dor123
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Re: How MH lamps can make 3000K color with Na-Sc? « Reply #3 on: August 06, 2024, 03:00:56 AM » Author: dor123
So why the length of the sodium line in the spectrum of my Sylvania HSI-TD 70W/WDL, is the same as in the spectrum of my Electra/Venture MH-DE 70W 4200K Rx7s lamp?
1. https://www.lighting-gallery.net/gallery/displayimage.php?pos=-246515
2. https://www.lighting-gallery.net/gallery/displayimage.php?pos=-183300
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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.

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