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Home | All Our Brands | Extech Instruments | Thermo-hygrometer | Extech RH390 Precision Psychrometer

Extech RH390 Precision Psychrometer

item#: EXT079

The Extech Precision Psychrometer RH390 has a high 2% RH accuracy, a fast response time (less than 30 seconds), and a dual backlit display. The RH390 can simultaneously display humidity/temperature, humidity/dew point, or humidity/wet bulb measurements. Scroll down to see more RH390 digital psychrometer features and specifications.

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The Extech RH390 Precision Psychrometer is available with standard factory calibration or with NIST Calibration Certification (adds 5 days to product lead time).

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The Extech RH390 Precision Psychrometer offers the highest 2% RH accuracy with a fast, 30 second response time. All of Extech assessment tools are factory calibrated to specifications and work to spec.

Features - Extech RH390 Precision Psychrometer

  • Offers a dual backlit display
  • Made with a slim design with rubberized sides for better grip and for one hand operation
  • Includes Data Hold and Min/Max functions
  • Auto-powers off with disable feature
  • Alerts user with low battery indicator
  • Has a simultaneous display of humidity/temperature, humidity/dew point or humidity/wet bulb

Model Includes:

  • 9V Battery
  • Carrying case

Technical Specifications

Humidity 0 to 100%RH
Internal Temperature -4 to 199°F (-20 to 100°C)
Basic Accuracy 2%RH, 1.8°F/1°C
Max Resolution 0.1%RH, 0.1°F/°C
Dewpoint -22 to 199°F (-30 to 100°C)
Wet Bulb 32 to 176 °F (0 to 80°C)
Dimensions 7.8" H x 1.7" W x 1.3" D
Weight 7 oz (200g)

Customer Reviews

Extech RH390 Precision Psychrometer
5 Stars based on 2 Review(s)
5 Stars

Excelent Product
June 1, 2010
Precision and good product

5 Stars

Excelent Product
May 28, 2010
Excelent Product, Price/Value, as its named Precision

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