UV Lamp hours keep  increasing when HPLC system is at standby mode

Hi,

I know system is very old and I start using it from 2016 . This system don’t have Lab Advisor install on it and after looking into maintenance logbook for this HPLC detector, all it say UV lamp replaced in 2011 and visible lamp changed in 2012. I think I have to take lamp out to see if it’s from Agilent or from any other supplier .

Yes

Hello,

thanks for update (I wonder if my memories were incorrect,,,

Your question is classed "difficult" ......

Let me start easier one!  The visible lamp is not required replacing.  It seems working without error. that is typical "bulb" , if id is out the software tells you "current error" or something , (not like ignition error)

The UV lamps age ,in general, the lifetime is around 2000h as you know,

The 8100h is surprise! (Or someone missed to reset lamp hours! So today's DAD lamps have RFID tag recording correct "ITS" hours, as jhagel wrote , RFID information is reliable.)

Your test result tells us "the light intensity is low", possible causes are:

- aged lamp

- something in the cell (UV absorbing solvent, bubbles or everything to hide beam!)

- dirty flow cell windows

- dirty or aged windows/lens of optical unit

- other malfunction

And your detector is old model (as sschombu wrote)

Replacing to new genuine lamp is good idea in many cases :-) but sometimes  NOT for aged detector, If lens/windows/cell/windows/grating are dirty or burnt and you replace NEW-lamp, the light intensity will not recover and intensity test will fail. In this case you need to ask to repair of DAD. (and you can't return new-lamp... )

I have no idea for repair parts availability (some are already gone...), so I recommend to ask local Agilent's service..., 

possibility ,price, parts availability and risk of costs.

In some cases you have no need to replace UV lamp:

- you can do your analysis without any problem.

- your chromatogram's noise is within YOUR specification

- your chromatogram have now explicit drift or hiccup

- your boss/customer/regulations permits use of old lamp.

Sorry for complicated advices ,

Regards,

ps : If it's mine I will try to wipe two window in cell compartment with a clean wipe and non-metal toothpick..... only two window in cell room ! and leave it half day. I can't give you guarantee...

Hello everyone,

Are there any "correct" comments ???

Regards,

Thank you , I found UV & visible Lamp hours. It show  that lamps was replaced in 2011 and 2012 and accumulated hours on lamps are 8137.65hrs(UV ) and 9248.47hrs(visible)---shocked to see these many hours on lamps . Most HPLC lamps are good for ~2000 – 3000hrs. I ran intensity test and it failed at “Lowest intensity “ in range from 190-220nm,221nmn-350nm, 351nm-500nm and 501nm-950nm but pass at highest intensity in range from 190nm-30nm and 700nm-950nm and D2 alpha line. Other tests like DAD filter test, Holmium filter test and Dark current test passed. Does it mean I need to change both the lamps?

Regards

Monika

I don't think the hours are real. The D2 lamp very likely would be dead at 8000+ hrs. For Agilent long-life lamps we guarantee 2000 hrs and often see 3000-4000 hrs.

With regards to low intensity, a new D2 lamp might help, but cannot compensate for such ancient optic. Things like the achromat lens, but also the diode array itself age over time. Like I said before, the G1315A is fully out of support for almost eight years. Certain parts might still be available, but I would not invest too much money into such old detector. Definitely we don't have major parts like the optical unit or main board any longer, so you will be much better off with a new G7115A detector or a cheaper, used, but refurbished and certified G1315C or G1315D.