Table 1 lists the available HMT370EX measurement parameter options and their abbreviations and units for the standard probe options HMP371, HMP373, HMP374, HMP375, HMP377, and HMP378.
| Parameter | Abbreviation | Unit |
|---|---|---|
| Relative humidity | RH | %RH |
| Temperature | T | °C (°F) |
| Dew point temperature | Td | °C (°F) |
| Dew point / frost point temperature | Td/f | °C (°F) |
| Absolute humidity | a | g/m3 (gr/ft3) |
| Mixing ratio | x | g/kg (gr/lb) |
| Wet-bulb temperature | Tw | °C (°F) |
| Water concentration | H2O | ppmv |
| Water vapor pressure | pw | hPa (psi) |
| Water vapor saturation pressure | pws | hPa (psi) |
| Enthalpy | h | kJ/kg (Btu/lb) |
| Dew point temperature difference | ΔT | °C (°F) |
| Absolute humidity at NTP | aNTP | g/m3 (gr/ft3) |
| Water mass fraction | H2Ow | ppmw |
| Parameter | Abbreviation | Unit |
|---|---|---|
| Available for both HMP378F and HMP378H | ||
| Temperature | T | °C (°F) |
| Relative saturation | RS | %RS |
| Water activity | aw | |
| Only available for HMP378F | ||
| Water concentration in oil 1 | H2O (oil) | ppmw |
| Only available for HMP378H | ||
| Water concentration in JET A-1 fuel | H2O (fuel) | ppmw |
| Saturation temperature | Ts | °C (°F) |
1 The default calculation coefficients for water concentration in oil
(ppmw) are valid for mineral transformer oil. For more information on
default and oil-specific calculation coefficients, see HMP378F calculation model with average oil coefficients and HMP378F calculation model with oil-specific coefficients.