User guide
3-21
3.11.3 Purging Analyzer and Universal Power Supply and/or URD for Hazardous
 Areas (with On-Line Validation)
  • NEC/CSA Class 1, Division 2, Groups A-D
  • ATEX Zone 2 CAT 3 – Dual regulators must be used on the inlet!
The block diagram below shows the sections of the analyzer that require nitrogen purging when using in 
conjunction with either or the Universal Power Supply and Universal Remote Display. AZ-Type purge control 
system is fi tted the Launch Unit and it includes a local indicator (Bright Green, rugged light) and pressure switch 
alarm contacts (open on loss of purge pressure).
3.11.4 Purging Analyzer and Universal Power Supply and/or URD (not using On-Line Validation)
  • NEC/CSA Class 1, Division 2, Groups A-D
  • ATEX Zone 2 CAT 3 – Dual regulators must be used on the inlet!
The block diagram below shows the sections of the analyzer that require nitrogen purging. A Z-Type purge 
control system is fi tted the Launch Unit and it includes a local indicator (Bright Green, rugged light) and 
pressure switch alarm contacts (open on loss of purge pressure). The purging should be carried in sequence 
typically as shown below. All purge gas connections are ¼” od Tube fi ttings.
Main
Electronic
Housing & 
Purge
System 
Laser
Module
Check Gas 
Flow Cell 
Process 
Interface
Process 
Interface
Detect
Module
Detect
Electronic
Housing
Nitrogen or I/A Purge 
Gas 
Nitrogen or I/A Purge 
Gas 
Power
Supply 
or URD 
Figure 27 - Purge Flow Diagram when using on line validation
Nitrogen or I/A Purge
Gas
Check Gas
Flow Cell
Detect 
Electronic
Housing
Main
Electronic 
Housing & 
Purge
System 
Laser
Module
Check Gas 
Flow Cell 
Process
Interface
Process
Interface
Detect 
Module
Detect 
Electronic 
Housing 
Nitrogen or I/A Purge Gas 
Power
Supply
or URD 
Figure 28 - Purging Analyzer for Hazardous Areas -NO- On-Line Validation
Main 
Electronic 
Housing 
& Pureg 
System
Detect 
Electronic
Housing
Power 
Supply
or URD
Check Gas 
Flow Cell
<3 INSTALLATION AND WIRING>
IM 11Y01B02-11E-A 5th Edition :June 5, 2012-00










