The HDR200 series is a family of humidity probes and electronic modules that offer % RH and dew point measurements with NIST traceable calibration. The all-stainless-steel probe construction coupled with a high temperature cable allows up to 200°C operations. For pressure applications, the probe is capable of handling 750 psi.

It comes in 2 versions, dew point (HD200) and % RH (HR200). The HD200 pressure version features an enhanced calibration for measuring dew points down to -60°C. The HR200 relative humidity version has an accuracy of ±1.0% at 25°C. The probe and electronics provide a single two wire loop powered by a 4 to 20 mA interface. The units accept a voltage source from 12 to 28 VDC (24 VDC is recommended). These units will display temperature along with RH or dew point depending on the version selected. The RS-232 allows a user to scale their output ranges as well as displayed units. The unit and sensor are connected via a 1-meter high-temperature cable.