A new digital psychrometer, Model RH401, features a built-in infrared (IR) thermometer ideal for noncontact and hard-to-access surface temperature measurements, the company says. The backlit triple display of the unit enables the simultaneous viewing of relative humidity and surface temperature readings, along with those of air temperature, dew point (DP) or wet bulb. The RH401 measures both ambient and surface temperatures and automatically calculates the T1 (IR surface temperature) - DP differential. The thermometer has an 8:1 distance-to-target ratio with an adjustable emissivity from 0.3 to 1.0. The unit's humidity capacitance sensor is retractable to protect it during transportation and storage.

Extech Instruments, 285 Bear Hill Rd., Waltham, MA 02451; 781-890-7440; www.extech.com.

eProduct #189