Manufacturer: Philips
Model: SON-T 250W E40
Application: Industrial floodlighting
Wattage: 250W
Diameter (max): 45mm (T-45)
Length: 250mm
Tube Length: 90mm 7mm diameter
Bulb/Tube material: Polycrystalline Alumina
Colour Temperature: 2000K
Peak output wavelength: N/A - Broadband Emission
Total light output: 25'000 Lm
Rated lifetime: 24'000 Hours
Cap: E40
Operating voltage: 100V
Operating current: 3A
Warmup/restrike time: 5 minutes/10-15 minutes
Cost (original): Unknown
Value (now): Compatible lamps available from BLT Direct - Cost GBP 9.10 (Aug 2009)
Place of manufacture: Belgium
Date of manufacture: May 1992
Current Status: Working

This is a lamp which was at the time of its manufacture, and still is to this day one of the main workhorses of the industrial lighting sector.  This is not really surprising when you take into account that it is a very good "all round" lamp.  Not really *excelling* in any field, but more importantly, not having any huge drawbacks either.  It's very efficient, has a relatively long life, acceptable (by industrial standards) colour rendering ability, does not require hugely expensive or complex control gear (especially true of the variants of this lamp which feature an internal igniter - this one does not however, and requires an external igniter), and the lamps themselves are cheaply and readily available.  BLT Direct for example have a lamp of identical specification to this one available.

I believe this was the first (and by no means the last) lamp to find its way into my collection through being rescued.  I discovered it still fitted to an apparently nearly new Fitzgerald LB250SON low bay floodlighting fixture on a junk pile where a local warehouse was being torn down.  I enquired, found that it was getting scrapped and that I was welcome to it, so I took it.  At age twelve...and carried the whole darn thing home!  Incidentally, it seemed an awful lot heavier back then than it does now.  I should have known back then that this wasn't an interest that was going to disappear.  I had a couple of light bulbs then, just because they were interesting things I I actually do not know how many there are!  This is the 43rd one to be entered into the Virtual Display Shelf anyway, and there are a LOT to go yet!

Typically of Philips' discharge lamps, the manufacturing of this lamp is so perfect that it is almost a work of art. 


Click Thumbnails for full size images.

This lamp added to the Virtual Display Shelf on the 9th November 2005 at 20:58.


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