7010 gc/ms/ms. Parametr autotune. Voltage at the HES source and EMV

Hello

I have 7010 ms/ms. And when I did autotune and I didn’t like the voltage on the HES and EMV source. The repeller voltage should be between 22 and 32 volts. I have 16 volts. Ion focus normal voltage -74 - 90 volts, I have -193 volts. And I also do not like the voltage on the EMV, it is 2220 volts, I think this is a lot, although it is permissible. I have two questions. What could be the reason for these deviations in voltages, is it necessary to change the source of the HES, or will it be enough to clean it? And the second question - where can I find more detailed information about the ms/ms settings?

I attach file autotune

regards, AzraelPDF

  • The turbo pump power is very low at 17 Watts - typical is 20-22 or so. The vacuum reading is incredibly low for a 7010, they typically are somewhere about 1x10-4 with the required gases on.  The Q2 tune ion peak shapes are ugly.  Do you have the Collision Cell 1.5 ml/min nitrogen and 4.0 ml/min helium turned on ?  It is required to be on for tuning -- and should be on all the time the instrument is being used.  It takes 15 to 20 minutes for the temperature of the CC to stabilize after flow changes, as well.   The HES needs the helium column flow to be between 0.8 and 1.4 ml/min of helium as well.   Please check the flows and get back.

  • yes, you right. collision cell it's off. so the vacuum is very low. this device uses only one quadrupole. MRM mode not use. My interest more HES source and voltage on repeller/ion lense and EMF

  • It won't tune properly, then. The CC gas is required when running in any mode on a 7000x/7010x system. The tune algorithm wants it there. Your QQQ will not run like a SQ without it on, either.  The system calculates the mass axis delay caused by the CC and Quad2 distance during the tune.  You also should run in MS2 Scan mode with the scan speed at least 250ms/scan or slower. If you try to scan a QQQ faster you will get incorrect masses.

    Also the HES makes 10x to 20x more ions than the orthogonal, SS/Inert/Extractor, sources do.  The best way to utilize that is to inject the least amount possible at the lowest concentrations possible. Trying to jam more and more sample and matrix into the HES will require additional maintenance - source cleanings, source radiator cleanings, and more.

  • the device has been in operation for at least two years with the turn off gases of the collision cell. thanks for the valuable information about the modes of operation of the second quadrupole. I have another question.  In this device, the high intensity of m/z 44 (40000 counts) at the first filament. When I turned on the 2 filament, m/z 44 (280 counts)  were present, but the intensity was much less. I assume that this m/z44 is CO2 gas from the cylinder. But no fact.  But why such a difference in intensities depending on the choice of filament ?

  • It might make it to the end of a tune without the CC gases on and might not.  The algorithm is written around having them on, of course, so if you successfully ran the system without the CC gases on, you were fortunate.  

    The filament 1 is the one most used and filament 2 wasn't?  Filament age, use, sample contamination, oxidation, and alignment all play a part.  One filament also affects the other, especially in an HES where the two are immediately next to each other.  What about the tune ions and the two filaments? How much does 502 change F1 to F2, for example?  Filaments only have so much lifetime, too. If the filament itself looks pitted and rough through a magnifying glass, it should be replaced.

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