Long-term stability
HMP155 uses the proven Vaisala HUMICAP sensor that has excellent stability and withstands harsh environments. The probe structure is solid and the sensor is protected by default with a sintered Teflon filter, which gives maximum protection against water, dust, and dirt.
Warmed probe and high-humidity environment
Vaisala's patented, warmed probe provides reliable measurements in environments where humidity is near saturation and measurements may be corrupted by fog, mist, rain, and heavy dew. A wet probe may not give an accurate measurement in the ambient air.
As the sensor head is warmed continuously, the humidity level inside it stays below the ambient level. It also reduces the risk of condensation forming on the probe.
Fast measurements
With a fast response time, the additional temperature probe for HMP155 is ideal for measuring in environments with changing temperatures. The membrane filter speeds up the relative humidity measurement.
Long lifetime
Protecting the sensor from precipitation, and scattered and direct solar radiation increases its lifetime. Vaisala recommends installing HMP155 in one of the following radiation shields: DTR503, DTR13, or Stevenson screen.
For the additional temperature probe,
an installation kit is available for Vaisala DTR502 Radiation Shield.
Calibration
The probe can be calibrated using a computer with a USB cable, with the push buttons, or with the MI70 indicator.
Features
Optional warmed humidity probe and chemical purge
Plug-and-play
USB connection for service use
Use with DTR13 and DTR503 radiation shields and a Stevenson screen
Weather-proof housing IP66
Optional, fast temperature probe
Different output possibilities: voltage, RS-485, resistive Pt100
Applications: meteorology, aviation and road weather, instrumentation.
