Teledyne T200, Руководство по эксплуатации, Страница: 226 / 425

Instrument Maintenance Teledyne API
– T200 NO/NO
2
/NO
X
Analyzer Operation Manual
224
7. Take out the components of the assembly:

spring

sintered filter

two O-rings

the orifice
Note
For the vacuum manifold only, you may need to use a scribe or pressure from the
vacuum port to get the parts out of the manifold.
8. Discard the two O-rings and the sintered filter and install new ones.
9. Reassemble the parts as shown in Figure 11-7.
10. Reinstall the critical flow orifice assembly into the reaction cell manifold or the
vacuum manifold.
11. Reconnect all tubing, power up the analyzer and pump. After a warm-up period of
30 minutes, carry out a leak test as described in Section 13.3.12.
11.3.11. CHECKING FOR LIGHT LEAKS
When re-assembled or operated improperly, the T200 can develop small gaps around the
PMT, which let stray light from the analyzer surrounding into the PMT housing. To find
such light leaks, follow the procedures below.
C
AUTION
–
Q
UALIFIED
P
ERSONNEL
O
NLY
This procedure is carried out with the analyzer running and its cover removed.
1. Scroll the front panel display to show then test function to
PMT
.
2. Supply zero gas to the analyzer.
3. With the instrument still running, carefully remove the analyzer cover.
WARNING
–
E
LECTRICAL
S
HOCK
H
AZARD
Do NOT touch any of the inside wiring with the metal cover or with 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 reaction cell as well as around the PMT housing.

The PMT value should not respond to the light, the PMT signal should remain
steady within its usual noise floor.
5. If there is a PMT response to the external light, symmetrically tighten the reaction
cell mounting screws or replace the 1/4” vacuum tubing with new, black PTFE
tubing (this tubing will fade with time and become transparent).
Note Often, light leaks are also caused by O-rings being left out of the assembly.
6. If, during this procedure, the black PMT housing end plate for the Sensor Assembly
is removed, ensure to replace the 5 desiccant bags inside the housing.
7. Carefully replace the analyzer cover. If tubing was changed, carry out a pneumatic
leak check.
06858E DCN7057