The Alpha Moisture Systems Model ADHT range are three wire, 24V powered, 4-20mA Dewpoint transmitters.
Incorporated into the design of these transmitters are advanced electronics allowing for a power supply varying from 18 to 30V DC and are configured to output a linear, isolated, 4-20mA signal for the chosen range.
Various dewpoint ranges are available covering an overall range from -110ºC to +20ºC dewpoint.