Ballast on rough pump in LC/MS

[haiedc]

Hi all,

Why đo I have to open the ballast on rough pump in LC/MS, while not in GC/MS?

Thanks.

[lmh]

In a GC, the vacuum pumps are removing a fairly small trickle of gas. In an LC-MS, they are removing a larger volume of vapour from a much less volatile liquid (the hplc solvent). The vacuum pumps therefore tend to accumulate solvent in their oil in the LC system, which isn't a problem in the GC system. The ballasting allows them to get rid of accumulated solvent, and keeps the oil cleaner.

[sindhu]

Hi,

Whatever Imh has told you is true