Campbell Scientific AM16/32A Multiplexer - Manual (Page 22)

AM16/32A Relay Analog Multiplexer
MUX POWER SHIELD
SHIELD
MUXSIGNAL
CR23X AM16/32 IN "4X16" MODE
GND
SETS 1-10
H1
L1
H2
L2
H1
L1
H2
L2
SETS 11-16
12V
GND
RES
CLK
COM H1
COM L1
COM H2
COM L2
COM
12V
G
C1
C2
EX 1
SE 1
SE 2
FIGURE 9. Wiring Diagram for Strain Gages and Potentiometers
#8 Additional Loops - Additional loops may be used if sensors that
require different measurement instructions are connected to the same
multiplexer. In this instance, like sensors are assigned to sequential
input SETS. Each group of sensors is measured in a separate loop
(steps 2 through 7, Table 2). Each loop contains clock and
measurement instructions, and all loops must reside between the
instructions that activate and deactivate the AM16/32A (Steps 1 and
9).
The instruction sequence for control of an AM16/32A is given on the
following page. The program format is a product of Edlog a
datalogger program editor contained in CSI's PC208W Datalogger
Support Software.
5.2 Multiple Loop Instruction Sequence
As shown above, the programs for operation of the AM16/32A are
essentially the same for all CSI dataloggers. To measure sensors of
different types, different measurement instructions may be used
within successive program loops. In the following example, each
loop is terminated with Instruction 95, and the multiplexer is not reset
between loops. The example demonstrates the measurement of two
dissimilar sensor types (i.e. strain gages and potentiometers).
The program and accompanying wiring diagram are intended as
examples only; users will find it necessary to modify both for specific
applications.
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