Chromatography Forum

Just to help settle a debate here, is it best to turn detector lamps off after use or to leave them on constantly ?

I was originally told it was OK to turn the detector off after use, but now a few people think it shortens lamp lifetime switching them off.

Confused

It depends. Follow the lamp manufacturer's guidance

Deuterium lamps ( UV ) are rated by operational hours ( 1000, 2000 etc ), not the number of ignitions, but do have a warm up period of a few minutes ( some older types might have 20 minute warmup ). They should be turned off if not used for an hour or more.

Incandescent and most tungsten halide ( visible ) also have lifetimes, but much shorter warmups combined with longer lifetimes, so can be turned off and on as required, unless the manufactuter uses the waste heat to assist thermal stability in the detector.

Some low-energy lamps, eg in refractive index detectors, require both thermal and emission stability and should be left on all the time, unless they are not going to be used for days.

I hope that doesn't confuse, and both sides of the debate can claim victory..

Please keep having fun,

Bruce Hamilton

There was discussion about this not long ago:
click here