by
Forse » Wed Mar 02, 2011 1:00 pm
Hi Rasmus,
from what you have described, i would remove the comlumn from the ms and blank off the ms transfer line.
I have done this. Same problems.
also remove and inspect the analyser lid / detector housing for any contamination. with the system still blanked off check again for air /water, hopefully you should now only have background levels. if not, open a mass window of around 80, span 40, and spray around the analyser housing / detector housing / source flange / ref inlets etc with a compressed air cleaner . depending on the air cleaner you should see a mass of interest shoot up when you spray around.
The analyser/detector looks fine, and all o-rings look good.
did you remove the pre filters from the main rods when cleaning them?
Yes.
double check all your connections for the outer source
The electrical connections? I cleaned them of with abrasive paper. They look clean.
if you drop the repellor to normal level ( 0.5 / 1) what happens?
I will report back on this.
what was the situation with the instrument before trouble occured? has it been vented / moved etc?
The instrument have been unable to do a auto tune the last few years. The MS can produce usable spectres and do at library search, but I really don't like having to max out the parameters and running with such a high multiplier.