PCE Instruments PCE-P18 - Calculated Values; Selection of Controlling Values for Analog Outputs

16
AH = 2,1668 
P
ws
 RH
100  (T + 273,2)
gdzie:
T → measured temperature [
o
C]
RH → measured absolute humidity [%]
DP → dew-point temperature [
o
C]
P
ws
→ saturated water vapor pressure (water vapor pressure) [mbar]
AH → absolute humidity [g/m
3
]
DP =
T
n
m
- 1
log (P
ws

RH
10000  A
)
Table 2
The factors used to calculate the dew-point
T [
o
C] A m T
n
< 0
6.119866 7.926104 250.4138
0...50
6.1078 7.5 237.3
50...100
5.9987 7.3313 229.1
DP → dwe-point:
DP → absolute humidity:
5.5.1. Calculated values
Based on the measurement of a temperature and relative
humidity, the P18D transducer calculates dew-point and absolute humi-
dity of the following dependencies.
5.5.2. Selection of controlling values for analog outputs
The P18(D) transducers in versions P18(D)-1XX, P18(D)-
2XX, P18(D)-4XX, P18(D)-5XX are equipped with two programmable
analog outputs (voltage or current). By default, the first analog output
is set for a presentation of the ambient temperature and the second
analog output is controlled by the value of the relative humidity. The ana-
log outputs can respond to any of the measuring or calculated values