Operator`s manual

SECTION 7. MEASUREMENT PROGRAMMING EXAMPLES
7-3
FIGURE 7.4-1. Thermocouples with External
Reference Junction
The temperature of the 107 Probe is stored in
input location 1 and the thermocouple
temperatures in Locations 2-6.
PROGRAM
01: P11 Temp 107 Probe
01: 1 Rep
02: 11 IN Chan
03: 1 Excite all reps w/EXchan 1
04: 1 Loc [:REF TEMP ]
05: 1 Mult
06: 0 Offset
02: P14 Thermocouple Temp (DIFF)
01: 5 Reps
02: 2 15 mV slow Range
03: 1 IN Chan
04: 1 Type T (Copper-Constantan)
05: 1 Ref Temp Loc REF TEMP
06: 2 Loc [:TC TEMP#1]
07: 1 Mult
08: 0 Offset
7.5 107 TEMPERATURE PROBE
Instruction 11 is designed to excite and measure
the Campbell Scientific 107 Thermistor Probe
(or the thermistor portion of the 207 temperature
and relative humidity probe) and convert the
measurement into temperature (
o
C). In this
example, the temperatures are obtained from
three 107 probes. The measurements are made
on single-ended channels 1-3, and the
temperatures are stored in input locations 1-3.
CONNECTIONS
The black leads from the probes go to excitation
channel 1, the white leads go to ground, and the
red leads go to single- ended channels 1, 2, and
3 (high and low sides of differential channel 1
and high side of 2).
PROGRAM
01: P11 Temp 107 Probe
01: 3 Reps
02: 1 IN Chan
03: 1 Excite all reps w/EXchan 1
04: 1 Loc [:TEMP #1 ]
05: 1 Mult
06: 0 Offset
7.6 207 TEMPERATURE AND RH PROBE
Instruction 12 excites and measures the RH
portion of the Campbell Scientific 207
Temperature and Relative Humidity Probe. This
instruction relies on a previously measured
temperature for temperature compensation
when computing RH. In this example, three
probes are measured. Instruction 11 is used to
obtain the temperatures of the three probes
which are stored in input locations 1-3; the RH
values are stored in input locations 4-6. The
temperature measurements are made on single-
ended input channels 1-3, just as in Example
7.5. The program listed below is a continuation
of the program given in Example 7.5.
CONNECTIONS
The black leads from the probes are connected
to excitation channel 1; the clear leads are
connected to ground. The red leads are from
the thermistor circuit and are connected to
single- ended channels 1-3. The white leads are
from the RH circuit and are connected to single-
ended channels 4-6. The correct order must be
maintained when connecting the red and white
leads; i.e., the red lead from the first probe is
connected to single-ended channel 1 and the
white lead from that probe is connected to
single-ended channel 4, etc.
PROGRAM
02: P12 RH 207 Probe
01: 3 Reps
02: 4 IN Chan
03: 1 Excite all reps w/EXchan 1
04: 1 Temperature Loc TEMP #1
05: 4 Loc [:RH #1 ]
06: 1 Mult
07: 0 Offset