Humidity and Temperature Transmitter for Demanding Meteorological Applications

EE33-M, from E+E Elektronik (Austria), is the newest addition to the well proven EE33 transmitter series for relative humidity (RH) and temperature (T). The heated RH sensor, the additional heating of the RH sensing probe and a separate T probe ensure highly accurate outdoor measurements even under condensation conditions. A special coating protects the RH sensor against pollution. Together with a radiation shield, EE33-M is ideal for high-end meteorology applications.

The heart of EE33-M is the innovative, monolithic HMC01 sensor, developed and manufactured in thin-film technology by E+E Elektronik. HMC01 combines the RH sensor and heating resistor on a single substrate. A dual heating system prevents condensation on the RH sensor, on the sensing probe and on the filter cap, which leads to extremely short response time and fast recovery after condensing conditions. The measuring principle with separate RH and T probes enables precise continuous measurement even at permanent high humidity. The proprietary E+E coating protects the RH sensor element and its leads against corrosive and electrically conductive pollution.

A radiation shield is essential for best performance outdoors. The sensing probes of EE33M match modern radiation shields with forced ventilation such as LAM630.

EE33-M calculates all RH and T related parameters such as dew point temperature, absolute humidity, and mixing ratio. An optional connection cable allows for easy adjustment and configuration of the transmitter. The optional RS485 interface enables a network of up to 32 transmitters.