Campbell Scientific AM25T 25-Channel Solid State Multiplexer - Manual (Page 26)

Appendix A. Single-Ended Measurements
03: BR Transform Rf[X/(1-X)] (P59) ;Calculate RTD resistance R/R0
1: 1 Reps
2: 1 Loc [ RefTemp_C ]
3: 10.025 Multiplier (Rf)
04: Temperature RTD (P16)
;Calculate reference temperature
1: 1 Reps
2: 1 R/R0 Loc [ RefTemp_C ]
3: 1 Loc [ RefTemp_C ]
4: 1.0 Mult
5: 0.0 Offset
05: Beginning of Loop (P87)
;Loop through thermocouple channels
1: 0 Delay
2: 25 Loop Count
06: Step Loop Index (P90)
;Set index to advance 2 locations/loop
1: 2 Step
07: Do (P86)
;Clock the AM25T twice
1: 41 Set Port 1 High ;Setting high then low is faster than pulsing w/21X
08: Do (P86)
1: 51
Set Port 1 Low
09: Do (P86)
1: 41
Set Port 1 High
10: Do (P86)
1: 51
Set Port 1 Low
11: Thermocouple Temp (SE) (P13)
;Measure the connected thermocouples
1: 2 Reps
2: 1 5 mV Slow Range
3: 1 SE Channel
4: 1 Type T (Copper-Constantan)
5: 1 Ref Temp (Deg. C) Loc [ RefTemp_C ]
6: 2-- Loc [ TC_1 ]
7: 1.0 Mult
8: 0.0 Offset
12: End (P95)
;End of loop
13: Do (P86)
;Turn off AM25T
1: 52 Set Port 2 Low
A.1.2 Single-Ended Voltage Measurement
Connect two single-end sensors to the differential AM25T input channel.
Connect the sensor shields to the ground terminals next to the input channel. Up
to 50 single-ended voltage sensors may be measured by two single-ended
datalogger channels (Figure A-2).
A-4