Advertisement

Problem with LCQ DECA

Discussions about GC-MS, LC-MS, LC-FTIR, and other "coupled" analytical techniques.

6 posts Page 1 of 1
I know that the Thermo LCQ DECA has been retired but I need urgent help on this one since we are still using one. At one point the temperature in the room rose due to malfunction of the AC and we suspect the temperature sensor shut down the RF supply. The room was cooled after fixing the AC and but the RF remained frozen with the -28 and 36 V power supply shutting down also. We have no RF on the system. The +28, -28 and +36 V failed on the diagnostic report and also the RF amp out, the RF modulation, the Detected RF and the Multipole Det. RF failed on RF(1). On RF(2) the following failed: the waveform amp. The Multipole RF DAC initially fails with a low value and then it begins to increment to the right value and passes. What is going on? Is the -28 V/+36 V power sully blown or the main RF pcb? Please help.
From what I remember, if a DecaXP stops working through high room temp, it should start working again spontaneously when the temperature drops. This is what actually happened in my original basic training on a DecaXPplus more than a decade ago!

Have you done anything inside the instrument? If so, check all the cables are still properly in place, especially the various little ribbon cables that can easily be dislodged - some of them are feedbacks from different boards, and if the feedback is missing, the instrument is convinced that the voltage is missing.

Coincidentally, we are scrapping a DecaXPplus. If you think any parts would be useful to you, I can always ask the boss if it would be reasonable/possible for us to donate.
From what I remember, if a DecaXP stops working through high room temp, it should start working again spontaneously when the temperature drops. This is what actually happened in my original basic training on a DecaXPplus more than a decade ago!

Have you done anything inside the instrument? If so, check all the cables are still properly in place, especially the various little ribbon cables that can easily be dislodged - some of them are feedbacks from different boards, and if the feedback is missing, the instrument is convinced that the voltage is missing.

Coincidentally, we are scrapping a DecaXPplus. If you think any parts would be useful to you, I can always ask the boss if it would be reasonable/possible for us to donate.
This is a follow up on the above. We got the LCQ DECA working after a long time due to procurement of spare parts. I am very interested in the DecaXPplus. Is it still available? We would appreciate the donation as it will change a lot of people's lives around here. How do I get in touch. My email is: leny2k@yahoo.com
I am really sorry, we've already disposed of the instrument. I'm glad you've managed to get yours going again. They were nice ion-traps, both the XPplus and the Advantage (the lower-spec model sold at the same time). In that era, I don't think Thermo were much good at making LC systems, so the DecaXP was always let down by its autosampler, but of course Thermo are now one with Dionex. I still think Thermo make very good traps, just currently don't have one of theirs.
Thank you any way. Perhaps its my fault. Should have followed immediately. Yes, I hear Agilent stopped making ion traps after buying Varian. I love ion traps but what can I do. They might get extinct soon.
Bruker and Thermo are still both very firmly designing and selling high-quality ion-traps, and have completely different design philosophies, so the world should still have them for a bit! Shimadzu currently sell an ion-trap ToF, but I have heard rumours their future intentions for accurate mass may go in a different direction - I don't know if they'll continue to make traps, or what their plans are. I have no idea who else out there is making traps.
6 posts Page 1 of 1

Who is online

In total there are 3 users online :: 0 registered, 0 hidden and 3 guests (based on users active over the past 5 minutes)
Most users ever online was 4374 on Fri Oct 03, 2025 12:41 am

Users browsing this forum: No registered users and 3 guests

Latest Blog Posts from Separation Science

Separation Science offers free learning from the experts covering methods, applications, webinars, eSeminars, videos, tutorials for users of liquid chromatography, gas chromatography, mass spectrometry, sample preparation and related analytical techniques.

Subscribe to our eNewsletter with daily, weekly or monthly updates: Food & Beverage, Environmental, (Bio)Pharmaceutical, Bioclinical, Liquid Chromatography, Gas Chromatography and Mass Spectrometry.

Liquid Chromatography

Gas Chromatography

Mass Spectrometry