Philips Ceramalux /w Alto 250W HPS

Here’s an unusual lamp, a coated 250W HPS from Philips. Coated SON lamps were common in Europe, but here we didn’t adopt them aside from select applications.

File information
Filename:	IMG_3047.jpeg
Album name:	me400r3 / The Best of My Light Bulb Collection
Keywords:	HPS / SON
Manufacturer:	Philips
Type/Model:	Ceramalux \| C250S50/D
Wattage:	250W
Date manufactured:	2001
Filesize:	66 KiB
Date added:	17 May, 2026
Dimensions:	640 x 546 pixels
Displayed:	50 times
URL:	http://80.229.24.59:9232/gallery/displayimage.php?pid=24967
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Comment 1 to 6 of 6

Page: 1

AngryHorse

[17 May, 2026 at 09:53 AM]

What’s the Alto bit?

Beta 5

[17 May, 2026 at 05:54 PM]

Lower mercury content?

me400r3

[17 May, 2026 at 06:38 PM]

Correct, Alto means lower mercury content. Federal regulations passed around the millennium.

Beta 5

[17 May, 2026 at 10:25 PM]

The same idea as the Also tubes then I guess? I wonder if some of the rather low mercury T8 and T5 tubes we had here in recent years (those which always start a very dim pink in the middle when cold, such as the Osram Lumilux T8's) would pass the same standard as the Alto lamps in the US did?

me400r3

[19 May, 2026 at 07:30 PM]

Correct. However, the Osrams I’m not too familiar with but I’m sure the industry as a whole started adopting similar strategies.

Beta 5

[19 May, 2026 at 09:00 PM]

Yeah, tubes in later years often boasted the low mercury content on the packaging, which usually went hand in hand with triphosphor tubes and their marketing too. We never had the Philips Alto range here but there were some Philips T5's with green caps which I think were reduced wattage versions.

Comment 1 to 6 of 6

Page: 1