Extech Instruments, one of the world's largest suppliers of test equipment and portable printers, is announcing the availability of its new Psychrometer Series. The series, includes models RH300, RH350 and RH401.

Designed for HVACR, mold prevention and plant maintenance applications, Extech's Psychrometer Series features large triple displays that allow for the simultaneous viewing of wet bulb, dew point, relative humidity and air temperature. Each psychrometer in the series incorporates the inputs from two external probes to display differential measurements.

Extech's RH300 has an external probe for calculating the differential T1-T2 (air temperature-external probe temperature) and T2-dew point. Using Type K probes, T1 and T2, the RH350 displays differential measurements as T1-T2, Air Temperature-Tl, and Tl-Dew Point. The RH401 includes a unique IR thermometer and calculates the T1-DP (IR Surface Temperature-Dew Point) differential.

The Psychrometer Series features large backlit LCD's to provide an easily readable display of switchable temperature units (fahrenheit or centigrade) with 0.1-degree resolution. In addition, minimum, maximum and average readings - with date and time -can be easily recalled on the LCD. Each psychrometer includes a built-in memory that can store up to 99 data points and protected sensors. It can also be field-calibrated. A built-in RS-232 interface (with optional RS-232 cable) utilizing Windows® Hyperterminal software allows downloading data to a PC for subsequent analysis.

Other features include a real-time clock, Auto Power Off, and a unique sensor cap that twists to closed position for protection during storage. An optional RH355 accessory kit is available which includes the RH350 psychrometer, two Type K temperature probes, 33% and 75% calibration bottles, a RS-232 cable, four AAA batteries and a carrying case.