Replacement of EI Ion Source

Required parts

Part name
Required quantity
EI ion source box
This is heat-treated.
Ion Source ASSY attachment/detachment jig
Used when removing the ion source box from the main unit.
Box screwdriver
Used when replacing the ion source box.
Lens 1 ASSY
This is the assembly of nut, spring washer, washer, plate, insulator and lens 1.
Lens 1
This is heat-treated.
Replace if this is broken.


Step 1

Before starting maintenance, perform the following steps in order from 1 to 3:

1 Allow GC/MS to come to an automatic stop. Wait until [Completed] is displayed.
2 Shut down LabSolutions.
3 Turn off the main switch of the instrument.

Step 2

Open the front door.

Step 3

Insert the ion source ASSY attachment/detachment jig(②) to the specified position and screw it in.


Wear clean gloves for working with the parts and tools. Wipe all tools with a soft cloth soaked with acetone to remove any dirt or grime.

Step 4

While holding the ion source ASSY attachment/detachment jig with your hand, loosen the two screws completely using the box screwdriver(③).

Step 5

Hold the ion source ASSY attachment/detachment jig and remove the ion source box assembly.


Place the removed parts on a soft cloth and prevent them from being contaminated.

Step 6

Remove the ion source ASSY attachment/detachment jig(①) and separate the ion source box and lens 1 ASSY(④).

Step 7

Using the box screwdriver, disassemble lens 1 ASSY.

Step 8

Prepare the new ion source box and lens 1.

Step 9

Assemble the ion source.
Insert parts in the following order: Lens 1(⑤) → Insulator(⑥) → Plate(★1) → Washer(★2) → Spring washer(★3) → Nut(★4).

Step 10

Lightly tighten the nut with your hand while holding the plate.
Using the box screwdriver, carefully tighten the nut of the lens 1 ASSY.


Applying excessive force may cause lens 1 to warp and/or the insulator to break.

Step 11

Fit the lens 1 ASSY into the ion source box while aligning the holes for the jig, the two protrusions on the plate, and the two holes in the ion source box.

Step 12

Attach the ion source ASSY attachment/detachment jig.
Hold the ion source ASSY attachment/detachment jig and fit the ion source box assembly into the instrument.


Hold the jig as shown in the figure and tentatively draw the two screws out of the plate to facilitate installation.

Step 13

Using a box screwdriver, lightly tighten the two screws, starting from the screw on the left side. Remove the ion source ASSY attachment/detachment jig. Tighten the two screws completely.

Step 14

Check for any dirt adhesion on the O-ring mating surface(★1) of the vacuum container and the O-ring(★2).

Step 15

Close the front door.

Step 16

Start up the GC/MS.

Step 17

Launch the [Analysis] program and click [Detail] on the instrument monitor.

Step 18

  1. Display the [Consumables (MS)] tab in the [Monitor Details] window. Record the usage time of [Ion Source].

Recording the ion source usage time is recommended if you are planning to reuse the removed ion source next time.

  1. Click the [Consumables Reset] button.

Step 19

  1. In the [Consumables Reset] window, enter "0" in the Ion source field and click the [Set] button. After applying the setting, click [OK].

  1. Click [Close] in the [Monitor Details] window to close the window.