Campbell Scientific HMP35C Temperature and RH Sensor - Manual (Page 10)

HMP35C TEMPERATURE AND RH PROBE
8
TABLE 8. Wiring for Example 3
Description Color CR10(X)
Temperature Orange SE 3 (2H)
Relative Humidity Green SE 4 (2L)
Temperature Signal Reference White AG
Temperature Excitation Black E1
Power Control Yellow C1
Power Red 12 V
RH Signal, Power, & Control Reference Purple AG
Shield Clear G
Example 3. CR10(X) Program that Measures the HMP35C
in an Electrically Noisy Environment
;Measure the HMP35C thermistor.
;
01:
AC Half Bridge (P5)
1:
1 Reps
2: 22 7.5 mV 60 Hz Rejection Range ;CR500 (7.5 mV); CR23X (10 mV)
;21X, CR7 (15 mV)
3: 3 SE Channel ;Orange wire (SE 3), White wire (AG)
4: 1 Excite all reps w/Ex 1 ;Black wire (EX 1)
5: 2000 mV Excitation ;CR500, CR23X (2000 mV); 21X, CR7 (4000 mV)
6: 1 Loc [ T_C ]
7: 800 Mult
8: 0 Offset
;Compute the temperature in degrees Celsius.
;
02:
Polynomial (P55)
1:
1 Reps
2: 1 X Loc [ T_C ]
3: 1 F(X) Loc [ T_C ]
4: -53.46 C0
5: 90.807 C1
6: -83.257 C2
7: 52.283 C3
8: -16.723 C4
9: 2.211 C5
;Apply the temperature multiplier.
;
03:
Z=X*F (P37)
1:
1 X Loc [ T_C ]
2: 1 F ;See Table 4 for alternate multipliers
3: 1 Z Loc [ T_C ]
;Apply the temperature offset.
;
04:
Z=X+F (P34)
1:
1 X Loc [ T_C ]
2: 0 F ;See Table 4 for alternate offsets
3: 1 Z Loc [ T_C ]