Campbell Scientific AM16/32B Relay Multiplexer - Manual (Page 6)

Table of Contents
6.6 Thermocouple Measurement ............................................................. 30
6.6.1 Measurement Considerations ..................................................... 30
6.6.2 Single-ended Thermocouple Measurement ................................ 32
6.6.3 Differential Thermocouple Measurement .................................. 33
6.7 Mixed Sensor Types.......................................................................... 33
6.7.1 Mixed Sensor Example: Soil Moisture Blocks and
Thermocouples ....................................................................... 33
7. General Measurement Considerations ...................37
8. Installation .................................................................37
8.1 Mounting Tabs .................................................................................. 38
8.2 Controlling Humidity ........................................................................ 38
Appendix
A. AM16/32B Improvements .......................................A-1
Figures
2-1. AM16/32B Relay Multiplexer............................................................. 3
3-1. AM16/32B relay actuation time vs. temperature and battery
voltage.............................................................................................. 5
4-1. AM16/32B to datalogger power/control hookup using
CABLE4CBL cable ......................................................................... 6
4-2. Diagram showing advancement of channels using clocking
Mode B ............................................................................................ 8
4-3. Power and ground connections for external power supply................ 10
4-4. Typical AM16/32B to datalogger signal hookup (4x16 mode)
using CABLE4CBL cable.............................................................. 11
5-1. SCWin (Short Cut for Windows program builder)............................ 12
5-2. Example “4x16” mode program loops for CR23X, CR10(X),
21X, and CR7 dataloggers ............................................................. 20
5-3. Example “2x32” mode program loops for CR23X, CR10(X),
21X, and CR7 dataloggers ............................................................. 21
5-4. Wiring diagram for strain gages and potentiometers (uses two
CABLE4CBL cables) .................................................................... 22
6-1. Single-ended measurement without excitation.................................. 25
6-2. Differential measurement without excitation .................................... 25
6-3. Half bridge (modified 107 Temperature Probe) hookup and
measurement .................................................................................. 26
6-4. Potentiometer hookup and measurement (using CABLE4CBL
cable).............................................................................................. 27
6-5. Four wire half bridge hookup and measurement ............................... 28
6-6. Full bridge measurement ................................................................... 28
6-7. Full bridge measurement with excitation compensation ................... 29
6-8. Differential thermocouple measurement with reference junction
at the datalogger............................................................................. 31
6-9. Differential thermocouple measurement with reference junction
at the AM16/32B ........................................................................... 31
6-10. AM16/32B aluminum cover plate ..................................................... 32
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