12 using the switched 12 v to power sensors – Campbell Scientific CR23X Micrologger User Manual
Page 132
SECTION 8. PROCESSING AND PROGRAM CONTROL EXAMPLES
8-22
14:
Scaling Array (A*Loc+B) (P53)
1:
8
Start Loc [ _________ ]
2:
4
A1
3:
0
B1
4:
6
A2
5:
0
B2
6:
9
A3
7:
0
B3
8:
11
A4
9:
0
B4
15:
Z=F (P30)
1:
0
F
2:
0
Exponent of 10
3:
12
Z Loc [ _________ ]
16:
Beginning of Loop (P87)
1:
0
Delay
2:
4
Loop Count
17:
Z=X+Y (P33)
1:
8--
X Loc [ _________ ]
2:
12
Y Loc [ _________ ]
3:
12
Z Loc [ _________ ]
18:
End (P95)
19:
Z=X*F (P37)
1:
12
X Loc [ _________ ]
2:
1
F
3:
284--
Z Loc [ _________ ]
20:
End (P95)
21:
End (P95)
End Program
22:
P
End Table 3
*
A
Mode 10 Memory Allocation
01: 2500
Input Locations
02:
270
Intermediate Locations
8.12 USING THE SWITCHED 12 V TO
POWER SENSORS
In this example, it is required to measure air
temperature at two levels at a remote site where
AC power is not available. The station is
powered with a 12 V battery that is trickle
charged by a solar panel. Two 12 VDC
aspirated thermocouples (ASPTC) are used
measure air temperature. To minimize the
current drain of the ASPTCs, the fans are
turned on 20 seconds before the CR23X
measures the thermocouples. Immediately
after the thermocouple measurements are
made the fans are turned off.
The Switched 12 V terminal on the CR23X
wiring panel is used to power the ASPTCs. The
maximum amount of current that the Switched
12 V terminal can source is 600 mA at 50°C
(360 mA at 80°C). Each ASPTC draws 140
mA, for a total ASPTC current requirement of
280 mA (see Figure 8.12-1).