03-914978-00:1
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Chemical Ionization Options
adapter fitting and the long restrictor (03-930597-01). The long restrictor was
connected between the pneumatics manifold and the gas shut off valve before
the MCI module was installed. Protect the ends of the restrictors to prevent
contamination and plugging, when working on the assembly. The MCI Module
must have all of its ports connected for proper operation. If fewer than three
reagents are installed, then empty reagent bulbs must be installed in the unused
positions. Also, if the restrictors are removed for any reason, their ports must be
plugged with the pin plugs (17-783512-00) supplied.
1. Turn off all relays related to the MCI module.
2. If you have a
turbo pump system
, skip this step. If you have a
diffusion pump
system:
For each channel that will be worked on, close the associated needle
valve by turning the knob clockwise. Monitor the foreline pressure. Do not allow
it to exceed 500 mTorr for more than 20 seconds. This will reduce the inrush of
air into the vacuum system when the channels are reactivated.
3. Remove the MCI cover by loosening the thumbscrew on the front cover.
4. Loosen (but do not remove) the four screws located between the solenoid valves
on top of the module.
5. Remove the liquid reagent reservoir by gently rotating and pulling the bulb down
and out of the manifold. If there is unused liquid reagent remaining in the bulb,
and you wish to save it, cap the bulb with one of the vial caps (03-949870-04)
supplied in the accessory kit. You can use the reservoir stand (03-930073-01),
also found in the accessory kit, for storage.
6. Remove the lower restrictor (03-930596-02) installed in the two 1/8 inch ports
underneath the manifold block. Save the restrictor in a clean, particle free bag, to
prevent contamination and plugging.
7. Insert the short lower restrictor (03-930596-01) in these ports.
8. Attach the gas adapter (28-695138-00) to one end of the long restrictor (03-
930597-01) with the Teflon
®
ferrules. The gas adapters and Teflon ferrules are
found in the accessory kit. Teflon ferrules are used so that the gas adapter fitting
can be removed from the long restrictor, so that you may reuse it in its original
configuration. Ensure that the connection is tight to prevent leaks.
9. Fully insert the gas adapter into the ¼ inch inlet port of the channel and route the
long restrictor down and back so that it will clear the cover, when it is reinstalled.
10. Tighten the 4 screws on top of the module. The gas adapters and restrictor lines
will be held firmly by the O-ring seal after the screws are tight.
11. Replace the MCI cover and tighten the thumbscrew to hold it in place. Make sure
that all of the lines are free and clear of the cover before tightening the
thumbscrew.
12. Attach the free end of the long restrictor (03-930597-01) to your pressure
regulated gaseous reagent supply, set to 5 psi.
13. After installing CI reagent liquids, and each time a reagent liquid or gas is
installed, always use care when first opening the CI needle valves.
14.
If you have a
turbo pump
system
, skip this step.
If you have a diffusion
pump
system
, first turn on the relays. For each channel worked on, open the
needle valve slowly by turning the knob fully counterclockwise to clear out the air
in the lines. After a few seconds, return the valve setting to ½ open or their
previous setting (approximately 7 turns).
