Calculated parameters, Draft – ROTRONIC HM4 User Manual
Page 8

E-M-HM4-V0_08
ROTRONIC AG
Bassersdorf, Switzerland
Document Code
Unit
HM4 Humidity and Temperature Probe with
Heated Sensor
Instruction Manual
Document Type
Page 8 of 41
Document Title
© 2014; ROTRONIC AG
E-M-HM4-V0_08
3.3 Calculated Parameters
The HM4 can calculate all psychrometric parameters and assign them to the outputs with the HW4 software.
Dew point (Dp)
Frost point (Fp)
Wet bulb temperature (Tw)
Enthalpy (H)
Vapour concentration (Dv)
Specific humidity (Q)
Mixing ratio (R)
Saturation vapour concentration (Dvs)
Vapour partial pressure (E)
Water vapour saturation pressure (Ew)
Remark:
The above parameters are dependent on barometric pressure. Using the HW4 software, it is possible to store
the barometric pressure at the probe in the HM4 probe. Programming of the HM4 with the HW4 software is
described in the manual E-M-HW4v3-F2-023.
DRAFT