<5. INSTALLATION AND WIRING>
5-5
5-6
IM 11Y01B01-01E-A 6th Edition :Feb 13, 2013-00
5.5.1 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 sufficiently 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 flanges are provided with two diagonally opposed inlet ports (typically ¼” OD tube). Use Swagelok
(or equal) double ferrule tube fittings and connect both ports with ¼” OD stainless steel tubing to the purge gas
supply. The exact purge gas flow rate will be dependant upon the process conditions that exist at the flange
connection and therefore, the flow 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 flange 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 flanges, with and without any insertion purge tubes installed.
5.6 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 29 3” 150# Welded Metal Bellows Alignment Flange Shown above, with analyzer quick connect
