User Guide
Heavy Duty Psychrometer + IR Thermometer
Model HD500
Introduction
Congratulations on your purchase of the Extech HD500 Psychrometer. This handheld
meter measures and displays Air Temperature, Relative Humidity, Dew Point, Wet Bulb
and also Surface Temperature using the built-in IR thermometer. This meter is shipped
fully tested and calibrated and, with proper use, will provide years of reliable service.
Features
• Triple digital LCD display.
• Fast response, all data is calculated four times per second.
• Standard type k(NiCr-NiAl) Thermocouple input jack suitable for any style of type k
probe.
• Infrared thermometer to measure surface temperature.
• Red laser pointer included.
• LCD with Backlight
• Automatic range selection
• USB interface.
• Low battery indication.
• Auto Power off.
Safety
• Use extreme caution when the laser pointer beam is on
• Do not point the beam toward anyone's eye or allow the beam
to strike the eye from a reflective surface
• Do not use the laser near explosive gases or in other
potentially explosive areas
2
HD500 V3.1 12/07
Meter Description
1. Humidity & Air Temperature Sensor
2. Type K Thermocouple input jack
3. Laser pointer beam
4. IR temperature sensor
5. USB Interface
6. LCD Display
7. Upper display HOLD button
8. Upper display Temp./Wet Bulb/Dew Point button
9. Upper display record Max/Min button
10. IR Measurement button
11. °F/°C units button
12. Lower display HOLD button
13. Lower display record Max/Min button
14. Backlight button
15. Power button
NOTE: Battery Compartment, Tilt Stand and Tripod Mount are located on the reverse
side of the meter
Display Description
1. Low Battery icon
2. PC communication icon
3. Upper display function icons
4. Upper display
5. Laser pointer icon
6. Lower display function icons
7. Lower display
8. Lower display function icons
3
HD500 V3.1 12/07