The Model DPH-2020 Industrial Dew Point Hygrometer is a two-stage chilled mirror hygrometer for industrial process or lab applications. Includes NEMA protection of electronics. Dual-line digital display. Pressure rated to 30 PSI. DSP technology provides auto-correction for mirror contamination and "mirror clean" indication. Accuracy = � 0.1oC dew point over � 50oC; max depression 65oC. Zero hysteresis. Analog 4-20mA analog output and digital RS-232 port with graphical PC/Mac real time display software. Includes serial cable. Forced-air cooling with air filtering. Programmable output limit relays for process control automation. NIST traceable. Requires 110/220Vac. Optional microscope available.