Vaisala Humidity Transmitters

Vaisala HUMICAP® Humidity and Temperature Transmitters HMD60 / HMD70

The duct-mounted HMD60 and HMD70 humidity and temperature transmitters are designed for use in air conditioning applications where accurate and stable measurement of humidity and temperature is required.   The transmitters are easy to calibrate on-site without disturbing the measurement.  The transmitters incorporate the Vaisala HUMICAP® Sensor, which is known for its accuracy and long-term stability, negligible hysteresis and resistance to dust and most chemicals.   The HMD60/70 transmitters are available in two models: for humidity measurement only and for both humidity and temperature measurement.   Both true two-wire and three-wire models are available.

Technical specifications: Measurement range    0...100 %RH  Typical accuracy         ± 2 %RH Operating temperature:  - electronics        -5...+55 °C (+23...+131 °F)  - sensor head    -40...+80 °C (-40...+176 °F)

Vaisala HUMICAP® Humidity and Temperature Transmitter Series HMP230

The microprocessor-based HMP230 products are versatile and easy to use transmitters for demanding industrial and air conditioning applications.   The transmitters measure relative humidity and temperature.   As calculated variables they also output dewpoint and wet bulb temperature, mixing ratio and absolute humidity.   The HMP230 transmitters can be configured to the customer's requirements on the production line, but configuration and parameters can also be set by the user.  Both analog and serial outputs are available as well as several options: different cable lengths, power supply modules, serial interface modules and a local display.

Measurement range
      0...100 %RH

Accuracy against salt solutions
      ±2 %RH (0...90 %RH)
      ±3 %RH (90...100 %RH)

Max. accuracy against high quality certified standards
      ±1 %RH (0...90 %RH)
      ±2 %RH (90...100 %RH)

Operating temperature
       -40...+180 °C (-40...+356 °F)

Six models are available:

HMP231 for wall mounting

HMP233 for installation directly in processes in tight spaces

HMP234 for installation directly in processes & for measurement in pressures from vacuum to 10 MPa (100 bar, 1450 psig)

HMP235 for installation directly in processes & for measurement in temperatures from -40 to +180 ºC (-40 to 356 °F)

HMP237 for most demanding applications requiring an extremely rugged design

HMP238 for installations in pressurized pipelines to as high as 40 bar (580 psig)

Vaisala HUMICAP® Intrinsically Safe Humidity and Temperature Transmitter Series HMT360

The HMT360 transmitter can be installed directly into an explosive area, even those classified as having a constant risk of explosion (Zone 0 / Division 1).  The HMT360 complies with strict classifications from FM (USA), PTB (CENELEC, Europe), CSA (Canada), TestSafe (Australia) and TIIS (Japan). The transmitters measure relative humidity between 0...100 %RH. As calculated variables they also output dewpoint and wet bulb temperature, mixing ratio and absolute humidity. The structure of the transmitter is modular: the interchangeable probes are easy to remove and calibrate.

Accuracy against salt solutions
    ±2 %RH (0...90 %RH)
    ±3 %RH (90...100 %RH)

Max. accuracy against high quality certified standards
    ±1 %RH (0...90 %RH)
    ±2 %RH (90...100 %RH)

Operating temperature     -40...+180 °C (-40...+356 °F)
 

Five models are available for a variety of applications:

• HMT361 for wall mounting
• HMT363 for confined spaces
• HMT364 for high pressures (up to 100 bar/1450 psig) or vacuum
• HMT365 for high temperatures (up to +180 ºC / 356 °F)
• HMT368 for pressurized pipelines as high as 40 bar (580 psig)