Cleaning Or Changing Critical Flow Orifices; Checking For Light Leaks - Teledyne 100E Instruction Manual

Instrument Maintenance

9.3.5. Cleaning or Changing Critical Flow Orifices

There are a couple of critical flow orifices installed in the M100E, located on the exhaust
manifold. Refer to section 10.2.9.1 for a detailed description on functionality and
locations. Despite the fact that these flow restrictors are protected by sintered stainless
steel filters, they can, on occasion, clog up, particularly if the instrument is operated
without sample filter or in an environment with very fine, sub-micron particle-size dust.

9.3.6. Checking for Light Leaks

When re-assembled or operated improperly, the M100E can develop small leaks around
the PMT, which let stray light from the analyzer surrounding into the PMT housing. To
find such light leaks, follow the below procedures. CAUTION: this procedure can only be
carried out with the analyzer running and its cover removed. This procedure should only
be carried out by qualified personnel.
1. Scroll the TEST functions to PMT.
2. Supply zero gas to the analyzer.
3. With the instrument still running, carefully remove the analyzer cover. Take extra
care not to touch any of the inside wiring with the metal cover or your body. Do
not drop screws or tools into a running analyzer!
4. Shine a powerful flashlight or portable incandescent light at the inlet and outlet
fitting and at all of the joints of the sample chamber as well as around the PMT
housing. The PMT value should not respond to the light, the PMT signal should
remain steady within its usually noise.
5. If there is a PMT response to the external light, symmetrically tighten the sample
chamber mounting screws or replace the 1/4" vacuum tubing with new, black PTFE
tubing (this tubing will fade with time and become transparent). Often, light leaks
are also caused by O-rings being left out of the assembly.
6. Carefully replace the analyzer cover.
7. If tubing was changed, carry out a leak check (Section 11.5.1).
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Model 100E Instruction Manual
045150102 Rev XB1