User guide

3.5.1 Process Window Purge Gas Connection
In order to keep the process windows clean (prevent fouling by process gas) it is necessary to purge the
windows with a clean dry gas of suffi ciently low dew point.
When measuring Oxygen, Nitrogen should be used for purging the windows. The purge gas or nitrogen should
be clean (<0.5 μ particulate), dry (-40˚C dew point), oil free.
The process fl anges are provided with two diagonally opposed inlet ports (typically ¼” OD tube). Use Swagelok
(or equal) double ferrule tube fi ttings and connect both ports with ¼” OD stainless steel tubing to the purge gas
supply. The exact purge gas fl ow rate will be dependant upon the process conditions that exist at the fl ange
connection and therefore, the fl ow rate could be anywhere from 5lts/min to 50lts/min
(~10 SCFH to ~100 SCFH).
Ensure the purge gas line is clean and dry prior to connecting to the fl ange to ensure any condensate or
debris is not blown on to the windows at initial start-up. The same applies to both Launch Unit and Detect
Unit process fl anges, with and without any insertion purge tubes installed.
3.6 Mounting the Process Interface – standard 2”, 3”. 4” 150# ANSI RF or DN - 50/80
Alignment Nuts (x8)
Analyzer Quick Connect
Window Purge Port (x2)
Alignment Bellows
Alignment Studs (x4)
Analyzer Mounting Flange
Process Flange
Figure 7 3” 150# Welded Metal Bellows Alignment Flange Shown above, with analyzer quick connect
<3 INSTALLATION AND WIRING> 3-6
IM 11Y01B02-11E-A 5th Edition :June 5, 2012-00