INTERCAP® Humidity and Temperature Transmitter Series HMD/W80

The Vaisala INTERCAP® Humidity and Temperature Series HMD/W80 is a versatile product family designed for standard HVAC applications.

These cost-effective and reliable transmitters are easy to install and maintain.

Dew point temperature, wet bulb temperature and enthalpy output option available in selected models (see product datasheet for more details).

 Vaisala INTERCAP® Humidity and Temperature Transmitter Series HMD/W80

Vaisala INTERCAP® Humidity and Temperature Transmitter Series HMD/W80




Product Information

HMD/W80 family products includes the following products

  • Wall-mount temperature-only transmitters TMW82/83
  • Standard wall-mount humidity and temperature transmitters HMW82/83
  • IP65-classified wall-mount humidity and temperature transmitters HMW88/89(D) with and without display, for humid areas
  • Duct-mount humidity and temperature transmitters HMD82/83(D) with and without display
  • Outdoor humidity and temperature transmitter HMS82/8

Operating Principle

HUMICAP is a capacitive thin-film polymer sensor consisting of a substrate on which a thin film of polymer is deposited  between two conductive electrodes. The sensing surface is coated with a porous metal electrode to protect it from contamination and exposure to condensation.

The substrate is typically glass or ceramic. The thin-film polymer either  absorbs or releases water vapor as the relative humidity of the ambient air rises or falls. The dielectric properties of the polymer film depend on the amount of absorbed water.

As the relative humidity around the sensor changes, the dielectric properties of the polymer film change, and so does the capacitance of the sensor. The instrument’s electronics measure the capacitance of the sensor and convert it into a humidity reading.