Re-enabled HV outputs -> Spoke with Agilent service tech and problem may be related to the "Protect" mode of operation.  In this mode the HV will deselect if the pump current exceeds a programmable threshold (I had recently set all controllers to this mode).  The threshold current value programmed is much higher than should be experienced at our nominal pressures and this is the suggested mode of operation however if the current is "glitchy" it can result in the nuisance shut downs experienced of late (none of the other ion pump controllers have tripped off) -> I am now running this unit not in protect mode to see if problem persists.