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Extech RH390 Psychrometer
Extech RH390 Psychrometer
Extech / Thermometers

Extech RH390 Precision Psychrometer

The Extech RH390 Precision Psychrometer has a Relative Humidity accuracy of 2% with fast 30 seconds response time.

It can measure humidity and temperature simultaneously and has a dual-illuminated readout that can be alternated to display wet bulb and humidity, dew point and humidity or temperature and humidity.

    Extech RH390 Datasheet

    Extech RH390 User Manual

Categories: Environmental Testers, Extech, Thermometers Tags: EXTECH, Humidity
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  • Description

Measure humidity and temperature simultaneously with the RH390 Precision Psychrometer from Extech.

A dual-illuminated readout can be alternated to display wet bulb and humidity, or dew point and humidity, or temperature and humidity.

This handheld device registers temperatures from -3 degrees to 100 degrees C and measures the full spectrum of relative humidity with ±2% accuracy between 20 and 90% RH.

Extech RH390 Features:

  • Fast response time (<30 seconds)
  • Dual backlit display
  • Data Hold and Min/Max functions
  • Simultaneous display of:
    Humidity/Temperature
    Humidity/Dew Point
    Humidity/Wet Bulb
  • Slim design with rubberized sides for better grip and for one hand operation
  • Auto power off with disable and low battery indicator
  • Complete with carrying case and 9V battery

Automatic Power OFF

The RH390 has a default setting that automatically shuts the meter off after 10 minutes (indicated by a symbol on the display). This battery saving feature can be disabled by simply pressing and holding the “hold” button.

Extech RH390 Specification:

Function Range
Humidity 0 to 100%RH
Temperature (Internal) -30 to 100°C
Basic Accuracy ±2%RH, ±1°C
Max. Resolution 0.1%RH, 0.1°C
Dewpoint -30 to 100°C
Wet Bulb 0 to 80°C
Dimensions 200 x 45 x 33mm)
Weight 200g

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Ryan — Keysight / Rohde&Schwarz / GW Instek / Pendulum / Tekbox

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email: ryan@rapid-tech.com.au


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Mobile: +64 27 700 0178
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