English Datasheet

Precision Hygro-Thermometer
Highest 2% RH accuracy
With Grains per Pound (GPP) and Grams per Kilogram (g/kg) measurement
• Less than 30 second RH response time
• Water vapor in GPP (g/kg)
• Dual backlit display
• Simultaneous display of:
Humidity or GPP (g/kg) plus Temperature
Humidity or GPP (g/kg) plus Dew Point
Humidity or GPP (g/kg) plus Wet Bulb
• Slim design with rubberized sides for
better grip and for one hand operation
• Data Hold and Min/Max functions
• Auto power off with disable and low battery indicator
• Complete with carrying case and 9V battery
Specifically designed for HVAC and
water damage restoration contractors
Temperature (Internal)
Basic Accuracy
Max. Resolution
Wet Bulb
Absolute Humidity
0 to 100%RH
-22 to 199°F (-30 to 100°C)
±2%RH, ±1.8°F/1°C
0.1%RH, 0.1°F/°C
-22 to 199°F (-30 to 100°C)
32 to 176 °F (0 to 80°C)
0 to 1120GPP (0 to 160g/kg)
7.8x1.7x1.3" (200x45x33mm)
7oz (200g)
Ordering Information:
RH490 ..............Precision Hygro-Thermometer
RH490-NIST ....RH490 w/ Certificate of Calibration Traceable to NIST.
Specifications subject to change without notice.
2/22/12 - R1
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