Hello Isotope World On our Thermo Delta Plus XP, the HV has been turning off at 72- to 96-hour intervals when running in continuous flow mode. The HV will trip off and the monitor will display 0.34 KV in the HV textbox. Thermo service personnel kindly provided a cure that consisted of lengthening the capillary to the mass spectrometer to reduce the amount of gas entering the source. This cured the tripping off of the HV, but resulted in a substantial decrease in sensitivity (at least a factor of 2), and I can no longer analyze small samples. Has anyone else experienced this phenomenon and found a solution that does not result in substantial loss of sensitivity? Can anyone reccomend a good therapist? Many Thanks and Happy Isotope-ing! Linnea