5975C MSD tuning stopped

[milenuj]

Hi all

We have a Agilent 5975C MSD. I tried to autotune and an error message appeared during tuning :

Tune action stopped:the valid range for ent lens offset is 0.00 to 64

anyone has any idea of the possible cause of this matter?

Thanks!

[Steve Reimer]

Reload your last good tune file.

[M0n0]

Hello milenuj!

We have the same MSD and experienced the same error message. It might be difficult to find, but what the error says is, that the optimal voltage that would be applied to the entrance lens is higher than allowed. You can see this when tuning. The curve of the voltage ramp of the entrance lens does not have its maximum before 64V.

solution:

we took out the ion source and did two things:
1. the entrance lens itself has a contact which is connected to the cable applying the voltage. This contact was touching the outer metal surface of the ion source. Simple turning of the entrance lens was done.

2. Tech support told us, that there is this super small screw, which locks the inner insulator in the source body. This screw was said to possibly be responsible, when tightened too much. Try slightly loosening it.

This resolved the issues we were having with autotuning.