Chromatography Forum

Hi

I am working on a Varian 1200L MS/MS instrument (coupled with Varian CP-3800 GC). When I start performing an auto-tune (FC-43 positive EI) on this instrument, the initial hardware diagnostics shows a window with a warning 'Lens 3 is not working properly'. When I choose to proceed with auto-tune anyway, the tuning is successfully completed.

However the ratio of m/z 28 : 18 is much too high (percentages of 100% for 28 and 6.1 % for 18, which makes the ratio of 16.4 : 1, and I found that the limit is 1.2 : 1). Therefore, I need to check the instrument for possible leaks. I do not know too much about it but probably it is a significant leak isn't it?

Coming back to the lens. Probably the warning is a separate issue from the leak. What can I do in this matter? Can I somehow find out in exactly WHAT way it is not working properly? What may be the consequences of working on the instrument with one of the lenses not working properly? I will be very grateful for any comments and help.

I haven't seen the Lens 3 problem, but I have seen problems with my Varian 1200L. You may want to try calling Bruker - they seem to be the only people out there who have any working knowledge of the Varian 1200L systems. The first line of defense at Agilent will claim no knowledge or support of the 1200L, but I know there are at least three guys at Agilent who have experience with the 1200 - Curtis Camp, Martin Brown and Todd Osbourne (per my sales rep, that is). If you have an Agilent rep, you may want to shoot them an email to see if he/she can get you in touch with one of those guys.

Remove Lens3 from the source block and try the diagnostics again. If it passes, Lens3 needs replacing. Had to repace mine last month.

Rarobins, did you have to change the lens in Varian 1200L MS/MS or are you working on different instrument?

I was told by one of the Bruker technicians that there is no guarantee that the replacement of the lens will sort out the problem. Scratched and shorting out lens is option 1 (it is likely and would require replacement). The other 2 options are electronics boards located inside the system and would require an engineer and some expensive parts. He still recommends trying to replace lens 3 first and see how I get on but this lens is still expensive for me... So if I know that removing lens 3 will definitely tell me whether it is option 1 or not, it would be great.

thank you,
kamila