Instruction manual

AM16/32 Relay Analog Multiplexer
22
I-1 ‘set sub scan loop counter
SubScan (0,mSec,16)
PulsePort (5,10000) ‘Clock Mux
CS616 (Period(I),3,1,6,3,1.0,0)‘measure 3ea CS616 probes
I=I+3
NextSubScan
‘
For I=1 to 48 ‘convert CS616 period to Volumetric Water Content
VWC(I)=a0 + a1*Period(I) + a2*Period(I)^2
Next
‘
PortSet (4,0) ‘Set Mux Reset line Low
flag(1)= low
EndIf ‘+++++++++++++++++++++++++++
‘
CallTable Dat30min ‘Call Output Tables
NextScan
EndProg
5.4 General Programming Considerations
The excitation voltage, integration time, and delay time associated
with measuring the signal, and the speed at which the channels are
advanced can be varied within the datalogger program. In general,
longer delay times are necessary when sensors and datalogger are
separated by longer lead lengths. Consult your datalogger manual for
additional information on these topics.
6. Sensor Hook-up and Measurement Examples
This section covers sensor-to-AM16/32 connections as well as
AM16/32-to-datalogger connections. The following are examples
only, and should not be construed as the only way to make a particular
measurement. See the Measurement Section of your datalogger
manual for more information on basic bridge measurements. Most of
the following examples do not depict datalogger-to-AM16/32 control
connections (Section 4.1), but their presence is implied and required.
Campbell Scientific recommends that only sensor shield (drain) wires
be connected to AM16/32 shield terminals labeled (“
”).
6.1 Single-Ended Analog Measurement without Sensor
Excitation
Sensor to AM16/32 wiring - one single-ended sensor not requiring
excitation can be connected to an input SET with panel mode switch
set to “2X32”.
Multiplexer to Datalogger wiring - The COM signal line is input to a
single-ended analog input channel. The COM signal-ground line is
tied to “
” at the CR23X, 21X, or CR7, and to “AG” at the
CR10(X). Up to 32 single-ended sensors can be measured by one
single-ended datalogger channel in this manner.