Introduction
Congratulations on your purchase of the Extech RH401 Digital Psychrometer + InfraRed Thermometer. This device measures Humidity, Air Temperature, Dew Point and Wet Bulb. Advanced features include Infrared Non-Contact Surface Temperature Measurement, Data Hold and programmable Auto Power Off, and an RS-232 interface for capturing readings to a PC using optional 407752 software. The retractable probe protects the sensors when the meter is not in use. Careful use of this meter will provide years of reliable service.