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Dwyer Air Velocity Transmitter: 4 mA to 20 mA, 32°F to 140°F, 641-12 - Air Velocity Transmitters
DwyerAir Velocity Transmitters

Dwyer Air Velocity Transmitter: 4 mA to 20 mA, 32°F to 140°F, 641-12

The DWYER Air Velocity Transmitter (model 641-12) is an air velocity transmitter that outputs a 4 mA to 20 mA signal. It measures air velocity from 250 fpm to 15,000 fpm within an operating temperature range of 32°F…

SKU 3G-OTH-168000

Brand
Dwyer
Item
Air Velocity Transmitter: 4 mA to 20 mA, 32°F to 140°F, 641-12
Category
Air Velocity Transmitters
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Technical Specifications

Dwyer
Manufacturer Part Number
641-12
Type
32°F to 140°F, 641-12, 250 fpm to 15,000 fpm
Air Velocity Accuracy
+/-3% (32 to 122 °F)
Calibration Certificate
Not Included
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Dwyer Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The DWYER Air Velocity Transmitter (model 641-12) is an air velocity transmitter that outputs a 4 mA to 20 mA signal. It measures air velocity from 250 fpm to 15,000 fpm within an operating temperature range of 32°F to 140°F. The transmitter offers an air velocity accuracy of +/-3% over 32 to 122 °F. Note that a calibration certificate is not included with this unit.

Frequently Asked Questions

What is the Dwyer 641-12 air velocity transmitter used for?

The Dwyer 641-12 air velocity transmitter measures air flow in HVAC ducts, fume hoods, and cleanrooms. It outputs a 4 mA to 20 mA signal proportional to air velocity from 250 fpm to 15,000 fpm, making it suitable for ventilation monitoring and industrial air handling systems.

What are the specifications of the Dwyer 641-12 air velocity transmitter?

The Dwyer 641-12 measures air velocity from 250 fpm to 15,000 fpm with an accuracy of +/-3% over 32°F to 122°F. It operates from 32°F to 140°F and provides a 4 mA to 20 mA output. A calibration certificate is not included with this unit.

Where to buy the Dwyer 641-12 air velocity transmitter worldwide?

3G Electric supplies the Dwyer 641-12 air velocity transmitter worldwide. As a global industrial equipment distributor, we handle full logistics, customs clearance, and delivery to your site. Contact us for availability and lead time for your region.

How to install the Dwyer 641-12 air velocity transmitter?

Mount the Dwyer 641-12 in a duct with the sensing element perpendicular to airflow. Connect the 4 mA to 20 mA output to a compatible controller or PLC. Ensure the operating temperature stays within 32°F to 140°F. For best accuracy, avoid turbulent flow near bends or dampers.

Used in

Common applications for Dwyer
Combustion air-filter monitoring — Magnehelic Series 2000 on burner air-intake filter banks
Clean-room and pharmaceutical pressurisation — Magnehelic / Capsuhelic differential-pressure gauges
HVAC fan-discharge static pressure — Mark II inclined-vertical manometers on AHU test points
Filter-blockage alarms — Photohelic Series 3000 combined gauge/switch on air-handling units
BMS-integrated pressure monitoring — Digihelic DH3 with 4–20 mA output for building management

Dwyer Products

3G Electric supplies Dwyer air velocity transmitters. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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