How to Remove and Reinstall 5977 GC/MSD Ion Sources (EI/CI/HES)

Answer

This Information Applies To: Agilent 5977 GC/MSD

Issue

GC/MSD maintenance or repair tasks will require removal and reinstallation of the ion source within the analyzer assembly.

• Filament exchange
• Replacement of insulators
• Ion source cleaning.

Types of Sources

 It is important to identify the ion source type correctly when removing and re-installing an ion source to ensure that the electrical leads are reconnected correctly. Ion source type label is on the heater/sensor part. The label can be viewed using the source view window on the front of the 5977 vacuum housing or once the analyzer assembly has been opened.

The ion source wires will need to be disconnected to enable the removal of the ion source from the source radiator. 

1. EI and EI extractor source (Figure 1, Table 1)

Figure 1: EI and EI extractor source 
1. Ion source 2. Source feedthrough board 3. Thumbscrews 4. Extractor wire 5. Source heater and temperature sensor wires 6. Source radiator

Table 1: EI and EI extractor source wire color codes

2. CI source (Figure 2, Table 2)

Figure 2: CI source 
1. Ion source 2. Source feedthrough board 3. Thumbscrews 4. Source heater and temperature sensor wires 5. Source radiator

Table 2: CI source wire color codes

3. HES source (Figure 3, Table 3)

Figure 3: HES source 
1. Ion source 2. Thumbscrew 3. Source feedthrough board 4. Source finger grip 5. Thumbscrew 6. Source heater and temperature sensor wires 7. Source radiator

Table 3: HES source wire color codes

Steps to follow:

Remove the ion source

1. Vent the system. See How To Vent (Shut Down) the GC/MSD - EI - MassHunter 
   
   

   Caution: Always wear clean gloves to prevent contamination when working in the analyzer chamber

   
   

   Warning: The analyzers, GC/MS interface, and other components in the analyzer chamber operate at high temperatures. Do not touch any part until you are sure it has cooled close to ambient temperature.

2. Open the side plate of the vacuum chamber. See How to Open the Side Plate of the GC/MSD.

   Tips: Take a photo of the source before removing any wires and store it in a location easily accessed for future use. Use the photo when reassembling the source to ensure that wires are in the proper location for correct operation.

3. Disconnect the wires from the ion source. The source cannot be removed with the wires attached:

   Caution: When disconnecting wires pull on the connectors, not on the wires to prevent damaging the wires. Tweezers can assist with this task.

   
   
   1. For Standard EI source: Disconnect four filament wires (two white and two black), one repeller wire (red), one ion focus wire (orange) and one entrance lens wire (blue) from the ion source (Figure 1, Table 1)
   2. For Extractor EI source: Disconnect four filament wires (two white and two black), one repeller wire (red), one extractor wire (brown), one ion focus wire (orange) and one entrance lens wire (blue) from the ion source (Figure 1, Table 1)
   3. For Standard CI source: Disconnect four filament wires (two white and two black), one repeller wire (red), one entrance lens wire (blue), and one ion focus wire (orange) from the ion source. (Figure 2, Table 2)
   4. For HES source: Disconnect three filament wires (one grey, one white and one black) and one repeller wire (red) from the ion source (Figure 3, Table 3)
4. Remove the two large thumb screws that hold the ion source in place
5. Using the heater/sensor part (EI, EI Extractor and CI Ion Sources) or the finger grip (HES Ion Source) slide the ion source out of the source radiator. 

Perform required maintenance

Continue with disassembling, cleaning and/or replacement of parts and reassembling the ion source:   

1. How to Clean the EI/CI Source in the Agilent 5977A/B - GC/MS Articles - GC/MS Portal - Agilent Community, 
2. How to Clean the HES (High Efficiency Source) - GC/MS Articles - GC/MS Portal - Agilent Community
3. How to Disassemble and Assemble the HES (High Efficiency Source) - GC/MS Articles - GC/MS Portal - Agilent Community, 

Reinstall the ion source

1. Using the heater/sensor part or finger grip slide the ion source into the source radiator
2. Install the two large thumb screws that hold the ion source in place and tighten until finger tight
3. Reconnect the source wires (Figures 1, 2, or 3 and Tables 1, 2, and 3)
4. Close the side plate of the vacuum chamber
5. Pump down the system: How To Pumpdown (Start) the GC/MSD - EI - MassHunter - GC/MS Articles - GC/MS Portal - Agilent Community

    

   Confirmation: Wait a minimum of 2 hours (overnight preferred and essential for CI ion source) for the system to reach vacuum, thermal and chemical background equilibrium before operating the MSD with the filament on.

Learn how to effectively maintain and operate your 5977 GC/MSD: Agilent 5977 GC/MSD with OpenLab CDS Agilent 5977 GC/MSD with MassHunter Workstation  e-learning paths available from Agilent education