User manual

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Appendices
A. Absolute Humidity ................................................... A-1
A.1 Measurement Below 0°C ..................................................................... A-2
B. Changing the HC2S3 Temperature Range ............ B-1
B.1 HC2S3 Default Settings ....................................................................... B-1
B.2 Software and Hardware Requirements ................................................ B-1
B.3 Changing the Temperature Range ....................................................... B-2
B.4 Multiplier and Offsets for Temperature Range .................................... B-3
C. HC2S3 Digital Communications ............................. C-1
C.1 HC2S3 Digital Interface Specifications ............................................... C-1
C.2 HC2S3 Communications Protocol ....................................................... C-1
C.3 RS-485 Communications using an MD485 RS-485 Interface ............. C-3
C.4 RS-485 Communications using an SDM-SIO1 Serial I/O Module ..... C-5
Figures
7-1. HC2S3 and Met20 Radiation Shield on a vertical pole .......................... 8
Tables
8-1. Connections for Single-Ended Measurements ........................................ 9
8-2. Connections for Differential Measurements ......................................... 10
9-1. Temperature .......................................................................................... 11
9-2. Humidity ............................................................................................... 11
9-3. Wiring for Single-ended Measurement Examples ................................ 12
9-4. Wiring for Differential Measurement Examples ................................... 15
A-1. Wiring for Vapour Pressure Examples............................................... A-1