Teledyne 9110T instruction manual Checking for Light Leaks

Models: 9110T

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Model 9110T NOx Analyzer

Instrument Maintenance

 

1.

Turn off power to the instrument and vacuum pump.

 

 

2.

Remove the analyzer cover and locate the reaction cell (Figure 11-5 and Figure

 

 

11-6).

 

 

3.

Unscrew the 1/8” sample and ozone air tubes from the reaction cell.

 

4.

For orifices on the reaction cell (Figure 11-6): Unscrew the orifice holder with a

 

 

9/16” wrench.

 

 

 

This part holds all components of the critical flow assembly as shown in Figure

 

 

 

11-7.

 

 

 

Appendix B contains a list of spare part numbers.

 

5.

For orifices in the vacuum manifold: the assembly is similar to the one shown in

 

 

Figure 11-7, except:

 

 

 

Without the orifice holder, P/N 04090, and bottom O-ring, P/N OR34 and;

 

 

With an NPT fitting in place of the FT 10 fitting.

 

 

6.

After taking off the connecting tube, unscrew the NPT fitting.

 

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 9110T 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.

Teledyne Analytical Instruments

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Page 257
Image 257
Teledyne 9110T instruction manual Checking for Light Leaks, From the vacuum port to get the parts out of the manifold