Issue with relatively similar CPS from 7800

I have inherited a 7800 from a new job, when I run the standard method for the technique all of the counts come out relatively similar. Running a blank and then a calibration standard returns the same results, approximately. The instrument has been cleaned from the lens all the way back to replacing the sampling probe in the last couple of days. However, I still get relatively the same number for CPS of every element. I attempted to check each of our solutions via the signal monitor, only paying attention to Li. When I run the blank it returns a count of ~150 for Li and when I run the standard I get ~250-300 for Li, using the signal monitor. Along with cleaning everything, I also switched out all the standards for ones ran on a 7850 that came back fine on that instrument. I replaced the ISIS 3 the other day because it wasn't drawing up correctly and I just noticed that an error: 2607 Warning Y-axis movement disabled due to a partially closed top cover today. I am trying to figure out why this instrument returns the same values for all elements. They have not run this instrument for a couple of months and last batch I see, seems to have worked fine. Any suggestions or ideas would be helpful, I appreciate it.

Parents
  • Looks to me to be severely out-of-tune. If your probe ,nebulizer or cones are not blocked I would do a manual tune whereby I try each lens setting to see if the signal improves.

    With my tune solution (10 ppb Li, Y, Co, Ce, Tl) I notice that the Li signal decreases if the 10 ppb solution is old. I suggest you try to improve the Co (mz59) signal with a manual tune.

    Does your probe reach far enough into the tune solution?

Reply
  • Looks to me to be severely out-of-tune. If your probe ,nebulizer or cones are not blocked I would do a manual tune whereby I try each lens setting to see if the signal improves.

    With my tune solution (10 ppb Li, Y, Co, Ce, Tl) I notice that the Li signal decreases if the 10 ppb solution is old. I suggest you try to improve the Co (mz59) signal with a manual tune.

    Does your probe reach far enough into the tune solution?

Children
  • Lens, cones, bridge, nebulizer, rotor stator, lines, have all been cleaned. It might be an old tune solution but it is the low sensitivity that is giving me problems. After I flush the He line, I will try to get better CPS with a manual tune. I was able to get a higher count when I checked the signal monitor with gas on for He, I was getting about 3000 counts for Li but then switching back to no gas reduced the counts to about 600.

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