Chromatography Forum

Hello everybody,

work with an Agilent 7010B MS GC-MS. Yesterday I cleaned the ion source (HES) and when the vacuum was restored, I tried to do an autotune and an error message appeared, saying that I didn't have enough points to obtain a gain. I opened it and cleaned it again, now I try to autotune, with the filament energy at 100 uA, but the filament energy doesn't stop rising, it's already at 170 uA. I changed the settings and filament 1 and 2 have the same behavior. Has anyone ever experienced this?

Thanks!

Hello everybody,

work with an Agilent 7010B MS GC-MS. Yesterday I cleaned the ion source (HES) and when the vacuum was restored, I tried to do an autotune and an error message appeared, saying that I didn't have enough points to obtain a gain. I opened it and cleaned it again, now I try to autotune, with the filament energy at 100 uA, but the filament energy doesn't stop rising, it's already at 170 uA. I changed the settings and filament 1 and 2 have the same behavior. Has anyone ever experienced this?

Thanks!

My 7000C often has a problem that it reads a current even when the filament is turned off. It reads higher as the source temperature increases.

That it keeps increasing over time seems it could either be a firmware problem or a problem with the control board. I think that may be the main board on these instruments. I once had an Agilent ICP/MS where the EMV would drift higher several hundred volts during a run, then reset when the instrument plasma was turned off then on again. It was a problem with the board that controlled the voltage, so maybe it is the same with the filament.

What temperature is the source in your instrument? If you leave the heater off does it do the same thing?

Hello everybody,

work with an Agilent 7010B MS GC-MS. Yesterday I cleaned the ion source (HES) and when the vacuum was restored, I tried to do an autotune and an error message appeared, saying that I didn't have enough points to obtain a gain. I opened it and cleaned it again, now I try to autotune, with the filament energy at 100 uA, but the filament energy doesn't stop rising, it's already at 170 uA. I changed the settings and filament 1 and 2 have the same behavior. Has anyone ever experienced this?

Thanks!

My 7000C often has a problem that it reads a current even when the filament is turned off. It reads higher as the source temperature increases.

That it keeps increasing over time seems it could either be a firmware problem or a problem with the control board. I think that may be the main board on these instruments. I once had an Agilent ICP/MS where the EMV would drift higher several hundred volts during a run, then reset when the instrument plasma was turned off then on again. It was a problem with the board that controlled the voltage, so maybe it is the same with the filament.

What temperature is the source in your instrument? If you leave the heater off does it do the same thing?

I'm working with a source at 310°C. I turned off the temperature and the current really dropped! But it doesn't stabilize, so I can't do the autotune.

The current changing with source temperature is something I have not been able to figure out. The controller is outside the analyzer so it should not affect the control of the filament current when the source temperature increases, but even on my 7000C once it reaches 300C temperature the current will read 4uA even when the filament is off, and at 350C it will read 7uA.

Sounds like a call to Agilent to see if they have had the problem on other instruments.

The current changing with source temperature is something I have not been able to figure out. The controller is outside the analyzer so it should not affect the control of the filament current when the source temperature increases, but even on my 7000C once it reaches 300C temperature the current will read 4uA even when the filament is off, and at 350C it will read 7uA.

Sounds like a call to Agilent to see if they have had the problem on other instruments.

I changed the filament and now it stabilizes! Which was not an Agilent recommendation, because the filament was apparently fine. But now autotune does not pass the criteria of "High mass isotope ratio" and "High mass precursor ratio". It was reported that this is indicative of dirt in Q2. :/