AM32 MULTIPLEXER
20
7.4 21X PROGRAMMING EXAMPLE: HALF
BRIDGE MEASUREMENT WITH
COMPLETION RESISTOR(S) AT THE
DATALOGGER - 107 TEMPERATURE
PROBES
The 107 temperature probe can be multiplexed
with the AM32. The following diagram and
program depicts the setup required to make
temperature measurements. A similar program
could be used to measure other half-bridge
sensors.
The 107 probe does not need to be physically
modified to work with the AM32. The black
(excitation) lead is attached to LO and the red
(signal) lead is attached to HI at the multiplexer.
Insulate the white (ground) lead and tape it out
of the way.
At the datalogger, a 1k ohm 0.1% precision
completion resister is attached from the analog
input to ground. Sensor shields should be tied
together at the multiplexer and brought back to
earth ground at the datalogger.
COM HI is tied to an excitation channel and
COM LO to a single ended analog channel.
Instruction 22 is used to clock the AM32 with an
excitation channel.
FIGURE 7-4. Wiring diagram for example
using 21X datalogger to measure 107
temperature probes.
NOTE:
Tape the ground lead from the
sensor out of the way. Wiring is for pre
OSX-0.1, 1.1, 2.1 dataloggers
EXAMPLE PROGRAM FOR 21X
A PROGRAM TO MEASURE 107 TEMPERATURE PROBES.
*
1
Table 1 Programs
01:
5
Sec. Execution Interval
01:
P20
Set Port
enable the AM32
01:
1
Set high
02:
1
Port Number
02:
P87
Beginning of Loop
start loop to
01:
0
Delay
measure
02:
10
Loop Count
03:
P22
Excitation with Delay
01:
2
EX Chan
clock the AM32
02:
1
Delay w/EX (units=.01sec)
03:
1
Delay after EX (units=.01sec)
04:
5000
mV Excitation
Содержание AM32
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