Chromatography Forum

Hi, I'd like to share my experience with long life UV lamp for DAD, which specs is 2000 working hours and it worked only 800 hours. Unfortunately the manufacturer refused to replace the lamp. Could you please share with me your experience in similar case and how can proceed further in this situation?

Thank you in advance!

Hi
Most of the suppliers I know would replace quite readily, especially if it is within it's 'working' hours. The lamp market is v. competitive, with lots of choice. Also unlike many other consumables a lamp is not really open to user abuse.
Did they give a reason?

There are some possible reasons:
What Can Cause Early Failure or Reduced Life Expectancy of Deuterium Lamps?
Lamp ignition frequency
The number of deuterium lamp ignitions is inversely proportional to its useful output life. A practice of leaving the lamp on continuously will tend to decrease its useful life by about 3-fold, based on an eight-hour workday. However, turning the lamp on and off during the day for breaks, etc., will probably shorten lamp lifetime and will be less productive as the lamp needs to warm up for 30 minutes to stabilize.
Contamination of the outer envelope:
Do not touch the lamp with bare fingers. The oils, etc. from your skin will burn onto the quartz envelope, and produce a discoloration, which may reduce light emission or possibly lead to a stress failure. If you do touch the lamp surface inadvertently, swab the glass with isopropyl alcohol (2-propanol) to remove the contaminants before installing the lamp.
Physical shock
A physical shock to the instrument or detector module, when the lamp is hot, can damage or break the lamp filament. (At approximately 2700 degrees Kelvin, the filament is almost liquid when the lamp is on!)
Very Important: Always allow the lamp to cool down before turning it back on. Powering on a hot lamp may negatively impact the structural integrity of the filament.

Also, how long did the lamp sit on the shelf before you installed it? The difficulties in making a leak-free glass-to-metal seal mean that lambs will leak a small amount of D2. "New Old Stock" will have a shorter lifetime.

If the malfunction is not assignable to the user you should change the lamp supplier and let the previous one know it.As mentioned above, the market is very competitive and the lamps are quite expensive.