THERMOHYGROMETER

The thermohygrometer HD 9216 is a very compact portable instrument. Its high technological features are accompanied by a pleasing design. With its range of interchangeable probes, it is an indispensable instrument for measuring temperature and humidity in the fields of maintenance, heating/air-conditioning, laboratories, food and agriculture and all other sectors where relative humidity and temperature measurements must be precise, fast and repeatable. The HD 9216 is an easy instrument to use, even for unskilled operators. The humidity sensor is a condenser the dielectric of which is a hygroscopic polymer. As the dielectric constant for water is around 80, a strong variation of capacity is obtained with the variation of the humidity content of this polymer. The particular advantages of this type of sensor are good linearity, repeatability, insensitivity to temperature variations, brief response time and long life. The temperature is measured by a Platinum Pt100 thermoresistance (100W at 0°C); the temperature working range is limited by the temperature working range of the humidity sensor. Both the relative humidity and the temperature sensor are flat, with a high surface/volume ratio; this allows a good response time.