Vaisala HPP272, User Manual, Page: 3 / 66

Table of Contents
1. About This Document ................................................................................... 5
1.1 Version Information .......................................................................................... 5
1.2 Related Manuals ................................................................................................ 5
1.3 Documentation Conventions ...........................................................................5
1.4 Trademarks ........................................................................................................ 6
1.5 Patent Notice .....................................................................................................6
2. Product Overview ........................................................................................... 7
2.1 Introduction to HPP272 ....................................................................................7
2.2 Basic Features and Options .............................................................................8
2.3 Safety ..................................................................................................................8
2.4 ESD Protection .................................................................................................. 9
2.5 Measured Parameters .......................................................................................9
2.5.1 Understanding Relative Humidity and Relative Saturation ................10
2.6 Probe Filter ........................................................................................................11
2.7 Chemical Purge .................................................................................................11
2.8 Environmental Compensation for Pressure ..................................................12
2.9 Measurement Filtering Factor ........................................................................12
2.10 Connectivity to Vaisala Insight Software ......................................................12
2.11 Additional Features with Indigo Transmitters ..............................................13
3. H
2
O
2
Measurement ....................................................................................... 14
3.1 Operating Principle of H
2
O
2
Measurement .................................................. 14
3.2 Typical Applications ........................................................................................16
3.3 Condensation Monitoring ...............................................................................18
4. Installation .......................................................................................................20
4.1 Wiring ...............................................................................................................22
4.2 Power Supply .................................................................................................. 23
4.3 Setting Probe in Analog or Digital Mode .....................................................23
5. Operation ......................................................................................................... 25
5.1 Probe Start-Up ................................................................................................25
5.2 Behavior at Exposure to H
2
O
2
.......................................................................25
5.3 H
2
O
2
Concentration Reading When Not Exposed to H
2
O
2
.......................25
5.4 Modbus ............................................................................................................ 26
5.5 Operation in Analog Mode ............................................................................ 26
5.5.1 Analog Output Overrange Behavior .....................................................26
5.5.2 Triggering Purge in Analog Mode ......................................................... 27
6. Vaisala Insight Software ............................................................................ 28
6.1 Connecting to Insight Software ....................................................................28
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