ICP-MS 7850 AutoTune fail

Hi,

did you check if the "Sample Upatake Time" in the Peripump program enough? Maybe the tuning solution is not nebulized, which causes this error.

A normal setup with an SPS4 autosampler will take about 35s with a pump speed of 0.5prs, to uptake the solution.

We always set sample uptake time 30 s at a speed 0.30 rps. Earlier we didn`t have problems with these settings and all tunes were completed well.

Is it possible, that you are trying to tune a Gas mode ? 

And if so, have you recently exchanged the gas filter for the cell gases ?

Do you see a signal for 7, 89 and 205 in signal monitor in these batches ??

Yes, He mode.  The cell was purged with He previously.

No, we haven't changed the gas filter, It`s relatively new. 

We don`t see any signals in batches, they end abruptly at the start wit the warning. In startup tune we see these signals.

Maybe someone has adjusted the Helium Flow to an inadequate level.

In normal He-Mode it shoul be about 4-5ml/min.

Any other Gas in the Cell will cause the signal to be completely suppressed. So if the Gas Filter for examples is not purged enough (because it comes with nitrogen from the factory) you will have no counts.

Put the instrument in standby, and open the large cover. Behind the Cell MFC is a screw (or two if you have H2). Open this screw about 2.5 turns close it after 30min. Then your signal should come back, if it was related to "dirt" in the cell gases.

I`m sorry for not responding for such a long time. We had no electricity because of bombing from russia. 

He flow rate was 4,5 mL/min as usual. We have no other cell gases. The apparatus is quite new.

The purging operation that you suggested have been performed by system engineer during ICP-MS installation. After this we worked without problems. Until current issue popped up.

Also assuming that we have problems with He mode we created batch with both modes and it passed tunes perfectly. After this we carried out a couple of analyses with our usual methods with which we had problems previously. But today this "Auto tune failed because sensitivity is too low" appeared again. And the "trick" with method with both modes didn`t help.

I`m devastated.

Hi,

You probably tried everything already, but what I would do in your situation is do a manual tuning in the nogas  mode or the Helium mode (whatever you are going to use) and see if you can get any counts for Li7, Co59, Y89, Tl205 (agilent tuning solution 10 ppb).

Try changing all lenses (one at a time) to see if you can get higher counts.

Hello! 

Thank you. Next time we will try this.

Today we measured method only with no gas mode and it passed the tune. And after this all started working again. But it`s ridiculous. I can`t understand what can be the  reason of such strange behaviour.

Hello! 

Thank you. Next time we will try this.

Today we measured method only with no gas mode and it passed the tune. And after this all started working again. But it`s ridiculous. I can`t understand what can be the  reason of such strange behaviour.