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2 example cr23x program – Campbell Scientific AM25T 25-Channel Solid State Multiplexer User Manual

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AM25T Solid State Multiplexer

6.2.2 Example CR23X Program

The CR23X uses Instruction 134 for measuring thermocouples or voltages
with the AM25T. Example 5 is a portion of a datalogger program that uses the
instruction to measure 25 type T thermocouples. Instruction 134 automatically
compensates for long lead lengths.

TABLE 6-5. Wiring for CR23X Example

Function AM25T

CR23X

+12V Power

12 V

12 V

Power and Shield Ground

G

Clock CLK

C1

Reset RES

C2

RTD Excitation

EX

E1

Analog Ground

AG

Common High

HI

1H

Common Low

LO

1L

Example 5. CR23X Program for Measuring 25 Type T Thermocouples

;{CR23X}
;
*Table 1 Program
01: 1

Execution

Interval

(seconds)


01: AM25TMultiplexer (P134)
1: 25

Reps

2: 21

10 mV, 60 Hz Reject, Slow Range

3: 1

AM25T

Channel

4: 1

DIFF

Channel

5: 21

Exchan 1, 60 Hz Reject

6: 1

Clock

Control

7: 2

Reset

Control

8: 1

Type

T

(Copper-Constantan)

9: 1

Ref Temp (Deg. C) Loc [ RefTemp ]

10: 2

Loc [ TC_1 ]

11: 1.0

Mult

12: 0.0

Offset

18