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EXTECH Psychrometer: Onboard, Ambient Temp/Dew Point/Relative Humidity/Wet Bulb Temp - Data Logging Temperature & Humidity Meters
EXTECHData Logging Temperature & Humidity Meters

EXTECH Psychrometer: Onboard, Ambient Temp/Dew Point/Relative Humidity/Wet Bulb Temp

The EXTECH Psychrometer: Onboard (MPN RH390) is a data logging temperature and humidity meter that measures ambient temperature, dew point, relative humidity, and wet bulb temperature. It has a temperature range of…

SKU 3G-OTH-178802

Also listed as: RH 390 · RH-390

Brand
EXTECH
Item
Psychrometer: Onboard, Ambient Temp/Dew Point/Relative Humidity/Wet Bulb Temp
Category
Data Logging Temperature & Humidity Meters
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Delivery
Worldwide DHL shipping from Singapore; 7–14 business days door-to-door for most destinations.
Payment
Invoicing in USD. Bank transfer (SWIFT) and corporate PO accepted.

Technical Specifications

EXTECH
Manufacturer Part Number
RH390
Type
Ambient Temp/Dew Point/Relative Humidity/Wet Bulb Temp, -22°F to 199°F
Calibration Certificate
Not Included

Technical Documents

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EXTECH Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The EXTECH Psychrometer: Onboard (MPN RH390) is a data logging temperature and humidity meter that measures ambient temperature, dew point, relative humidity, and wet bulb temperature. It has a temperature range of -22°F to 199°F and does not include a calibration certificate.

Frequently Asked Questions

What is the EXTECH RH390 psychrometer used for?

The EXTECH RH390 psychrometer measures ambient temperature, dew point, relative humidity, and wet bulb temperature. It is used by HVAC technicians, plant engineers, and maintenance professionals for environmental monitoring, air quality assessment, and climate control in industrial and commercial facilities.

What are the specifications of the EXTECH RH390?

The EXTECH RH390 measures ambient temperature, dew point, relative humidity, and wet bulb temperature. Its temperature range is -22°F to 199°F. The device does not include a calibration certificate. It is a data logging temperature and humidity meter from EXTECH.

Where to buy the EXTECH RH390 worldwide?

You can source the EXTECH RH390 through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations. Contact us for availability and lead time on this data logging psychrometer.

How to use the EXTECH RH390 for wet bulb temperature readings?

To use the EXTECH RH390, power on the device and select the measurement mode for wet bulb temperature. Hold the sensor in the environment to be measured, allowing it to stabilize. The onboard display shows the wet bulb reading alongside ambient temperature, dew point, and relative humidity.

Used in

Common applications for EXTECH
HVAC system diagnostics — EXTECH AN340 vane anemometer for air velocity and humidity measurement
Industrial machinery maintenance — EXTECH 461995 laser tachometer for RPM and surface speed checks
Food and beverage quality testing — EXTECH RF12 analog refractometer for Brix concentration measurement
Refrigerant leak detection — EXTECH RD350 heated diode leak detector for R-513A systems
Environmental monitoring — EXTECH RH490 data logging hygro-thermometer for temperature and humidity logging
Lighting inspection — EXTECH LT300-NIST light meter for illuminance measurement in workspaces

EXTECH Products

3G Electric supplies EXTECH data logging temperature & humidity meters. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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