Campbell Scientific AM16/32A Multiplexer - Manual (Page 31)

AM16/32A Relay Analog Multiplexer
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0
"4 X 16" Mode
COM H (ODD)
COM L
COM H (EVEN)
COM L
ODD H
ODD L
EVEN H
EVEN L
SHIELD SENSOR SHIELDS COM
MUXSIGNAL
SHIELD
CR23X/
CR800/
CR850/
CR1000
21X/
CR7 CR10(X)
CR3000/
CR5000
EX E E VX
H H H H
L L L L
AG
G
FIGURE 13. Potentiometer Hook-up and Measurement
6.3.2 Potentiometer Measurement
Sensor to Multiplexer wiring – if panel switch is set to “4x16” mode,
up to two potentiometers may be connected to one input SET.
Excitation and ground leads may be common; signal leads must be
routed separately (Figure 13).
Multiplexer to Datalogger wiring - Signal lines from two COM
terminals are connected to two consecutive single-ended analog input
channels. One COM terminal is connected to a datalogger switched
excitation channel, and the remaining COM line connects to
datalogger ground. Up to 32 potentiometers may be measured by two
single-ended datalogger channels.
6.3.3 Four Wire Half Bridge (Measured Excitation Current)
Sensor to Multiplexer Wiring - one sensor per input SET. The panel
switch is set to “4x16” mode.
Multiplexer to Datalogger Wiring - One COM line is tied to a
datalogger excitation channel, and two COM lines to a differential
analog input. The remaining COM line is connected to the H side of a
resistor. The other
side of the resistor connects to the L side of the differential channel
and to ground (Figure 14). Up to 16 four wire half-bridges may be
ntial datalogger channels in this manner.
datalogger differential channel along with a fixed
measured by two differe
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