How to Replace the Electron Multiplier Horn - 5977 Series GC/MSD

Answer

This Information Applies To: Agilent 5977A/B/C GC/MSD

Issue

The Electron Multiplier Horn must be replaced when it is contaminated or the EMV value reaches 3000 V with a clean ion source.

Items Required

• Electron multiplier horn (5977B/C: p/n G7002-80103, 5977A: p/n G3170-80103)
• Gloves, clean, lint-free Large (p/n 8650-0030) Small (p/n 8650-0029)
• Long nose pliers or tweezers

Steps to Follow 

Warning: The analyzer, GC/MS interface, and other components in the analyzer chamber operate at high temperatures. Do not touch any part until you are sure it is cool.

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

Use Figure 1 as reference for this procedure.

Figure 1. EM horn installed in the detector.
1. Retaining clip, 2. EM horn, 3. Blue signal wire

Removing the EM Horn

1. Vent the GC/MSD

2. Open the analyzer chamber.

3. Open the retaining clip. Lift the arm of the clip up and swing the clip away from the electron multiplier horn. (See Figure 2)

   
   
   Figure 2. Releasing the retaining clip

4. Remove the electron multiplier horn.

5. Slide the blue signal wire from the connector in the side plate. (See Figure 3)

   
   
   Figure 3. Removing the EM horn

Installing the EM Horn

1. Hold the new horn with blue signal wire end down and attach the signal wire to the connector in the side plate. (See Figure 4)

   
   
   Figure 4. Attaching the signal wire

2. Slide the electron multiplier horn into position.

3. Close the retaining clip. (See Figure 5)

   
   
   Figure 5. Positioning the EM horn

4. Close the analyzer chamber.

5. Pump down the instrument

Learn more on how to effectively operate and troubleshoot your Agilent 5977 Series GC/MSD:  Agilent 5977 GC/MSD with MassHunter Workstation Agilent 5977 GC/MSD with OpenLab CDS Learning paths available from Agilent education