The Vaisala HUMICAP® Humidity and Temperature Transmitter Series HMT360 is the ideal solution for measuring humidity in hazardous areas.
The transmitters operate safely and reliably even in the most hazardous classifications. The HMT360 transmitters' proven performance and technology conform with rigorous international standards.
- Six interchangeable probe models for a variety of applications:
- HMT361 for wall mounting
- HMT363 for duct mounting and tight spaces
- HMT364 for high pressures up to 100 bar and vacuum conditions
- HMT365 for high temperatures
- HMT367 for high humidities
- HMT368 for pressurized pipelines up to 40 bar
- Intrinsically safe - the whole transmitter can be installed into the explosive area
- Complies with classifications from VTT (CENELEC, Europe), FM (USA), CSA (Canada), TIIS (Japan), and PCEC (China), VTT (IECEx)
- The interchangeable probe module contains all calibration coefficients, so a calibrated probe can be switched in the field without the need to input any data manually
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.