The Vaisala Humicap HMP155 humidity and temperature probe provides reliable humidity and temperature measurement. The HMP155 has a new generation Vaisala Humicap®180R sensor that has excellent stability and withstands harsh environments. The probe structure is solid and the sensor is protected with a sintered teflon filter, which gives maximum protection against liquid water, dust, and dirt.
Measuring humidity reliably is challenging in environments where humidity is near saturation. Measurements may be corrupted by fog, mist, rain, and heavy dew. A wet probe may not give an accurate measurement in the ambient air.
This is an environment to which Vaisala has designed a patented, warmed probe for reliable measuring. As the sensor head is warmed continuously, the humidity level inside it stays below the ambient level. Thus, it also reduces the risk of condensation forming on the probe.
The HMP155 is especially designed for use in meteorological applications, such as synoptic and hydrological weather stations, aviation, and road weather.