Venting and Shutting Down your Single or Triple Quadrupole LC/MS System

Answer

This Information Applies To: Agilent 6100 and 6400 Series LC/MS Systems controlled by OpenLab CDS ChemStation or MassHunter Workstation for LC/QQQ

Issue

How to safely vent and turn off your Agilent Single or Triple Quadrupole LC/MS system.

Tips: For single quadrupole LC/MS systems controlled by OpenLab CDS, se Turn off your Single Quadrupole LC/MS System Using OpenLab CDS

Background

The LC/MS system will need to be vented and turned off when the instrument will be idle for an extended time or when you need to do maintenance.

Requirements

Before you begin, check that the instrument has completed acquiring data or any tuning, and that you have saved all data as needed.

Steps to Follow

Caution: When you vent the instrument from within the Tune View, the LC/MS instrument does not turn off completely. Follow the entire shutdown procedure.

Warning: The spray shield and related spray chamber components are likely to be hot. Do not touch them until they have cooled to a safe temperature for handling. Always use powder-free nitrile gloves when handling LC/MS parts.

To vent the Instrument

1. Turn off the LC solvent flow. If you have analyte in any of the components in the sample delivery system, then it is important to flush the delivery system with pure solvent before you continue.
2. Check that the ballast valve on the rough pump is closed. (Not applicable for Agilent MS40+ Pumps)
3. In the Tune view of your data acquisition software (MassHunter or OpenLab CDS ChemStation), vent the system. When starting the vent process, the following occurs:
   1. Spray chamber voltages, the drying gas heater, the nebulization gas flow, the detector, and other specific lens voltages are all turned off.
   2. The drying gas flow is set to standby.
   3. If the APCI source is installed, the vaporizer heater is also turned off.
   4. If an Agilent Jet Stream source is installed, then the sheath gas heater is also turned off.
   5. The Rough Pump turns off when the turbo speed is below 20%.
4. Wait until the instrument completely vents, reaching a rough vacuum reading of 760 Torr, or atmospheric pressure. This process normally takes less than 10 mins and the rough vacuum readings can be monitored via MassHunter or OpenLab CDS ChemStation.

To shut down the Instrument

1. Turn off the MS using the power switch located in the lower left front corner of the instrument. (Figure 1)

   
   
   Figure1. Location of the front power switch on LC-QQQ instruments.
   
   

2. Unplug the main power cable leading to the LC/MS Instrument. Certain internal components are energized whenever the main power cable is connected even if the front power switch is turned off, so it is always safer to unplug this cable when venting.  

3. If the LC/MS instrument includes a pump expander box (see Figure 2), then turn off the pump expander box and disconnect the cable that is plugged into the mains receptacle.

   
   
   Figure 2. Pump expander location
   1. Internal Pump expander, 2. External pump 
   
   

Caution: Despite being shut down some heated zones such as source components will still have residual heat, so wait for heated components to completely cool down before handling heated to avoid injury.

The instrument is now safely shut down.