New Old Stock HPL Lamps that have turned brown

church

Active Member
I just opened a case of new old stock lamps, the date code on the box is the 23rd of September 1997 - I know I forgot about them in my lamp cabinet and they got pushed to the back. When I took one out of its box to install it I notied a small amount of brown discolouration in the gas and the quartz envelope was not as clear in the filament region as normal. I checked all twelve lamps and saw the same thing. The box of twelve had never been opened still taped shut with the manufacturr's original tape.

I have sent an email to the manufacturer providing all the detailed information from the cade label. This is why I didn't mention the name. these are the HPL575/115 version of the lamp.

Has anyone else seen this before?

I cannot take the lamps back to the supplier because they are no longer in business. Also I know I clearly keep far too many lamps when I can have a case of twelve get hidden like this.
 
Write the manufacturer rep for your area - even if your supplier went out of business, the lamps should still be able to be returned. If you need a way to contact them, your new supplier should be able to provide this if not handle such a return for you even if you didn't buy the lamps thru them.

Interesting, never seen that before. Should be easy enough to solve on the other hand.
 
Brown? That is odd. Age does not seam to matter in double sealed lamps, like PAR64's. I think I posted here last year that I found a large batch of 30 year old lamps new in the box. I put them into use last year, and they are all still working fine.

I am wondering about single envelope quartz. if there has been some degeneration to the envelope. Did you power any of them up? It might be interesting to do that on a variable transformer. If air has seeped in, the filament may give out some classic white smoke, or be black in color once cooled down. On the other hand, if it is some form of gas segregation, powering it up may clean it up after the usual 20 minute cycle.

Remember to tell us what you find!
 
Brown coloration typically indicates bromine gas. Sounds like a batch of bad seals. Never has happened to me, I have seen lamps stored away as old as 15-20 years (EHGs) that haven't developed any coloration. Sounds like these HPLs have bad seals. Have you fired one up? (If it is a leak, it might not be the best idea to power up a lamp, but if you do power it up, a very quick coloration coating will form, the other two colors are white and blue.
 
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I tried one lamp and it is working. However the manufacturer wants me to send the case of lamps to them - I wil send the eleven I have not used. I did some research that suggests this indicates faulty seals and the brown/yellow colour is the bromine gas. However from what I read I expect this to only occur after a lamp has been used. As I mentioned the box was unopened and still had the manufacturers inspection stamp across the sealing tape. As others have said I have lamps that have sat on the shelf for longer than this without problems - I even have some tungsten lamps that are 30 plus years old that I sll pull out from time to time on some older fixtures to use them up.

I shall let you know what I finout from the manufacturer.
 
I heard back from the manufacturer last week and apparently the lamps are good the discolouratinis a quirk of the gas they were using prior on lamps of that date code Using the lamp for 20 hours should will result in the brown discolouration going away. I was also told there area number of structural changes to the lampsince then that reduce filament shadowing. So far the lamp I installed is working finend when I checked the discolouration had indeed disappeared.
 

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