Extech RH390 Precision Psychrometer

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  • Dual backlit display
  • Simultaneous display of:
    • Humidity/Temperature
    • Humidity/Dew Point
    • Humidity/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


Humidity 0 to 100% RH
Temperature -4 to 140°F (-20 to 60°C)
Basic Accuracy ± 2% RH, ± 3°F/2°C
Max. Resolution 0.1% RH, 0.1°F/°C
Dewpoint -22 to 212°F (30 to 100°C)
Wet Bulb 32 to 176°F (0 to 80°C)
Dimensions 7.81x1.7x1.3" (200x45x33mm)
Weight 7oz (200g)

Extech RH390 Datasheet (RH390.pdf, 181 Kb) [Download]

Extech RH390 Manual (RH390_UM.pdf, 124 Kb) [Download]

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