Send a part number, a photo, or a whole BOM — we supply it and stand behind it. Worldwide shipping to 80+ countries.

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

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

The DWYER 641RM-12-LED is an air velocity transmitter with a 4 mA to 20 mA output, operating from 32°F to 140°F and measuring 250 fpm to 15,000 fpm. It offers an air velocity accuracy of +/-3% from 32 to 122 °F. This…

SKU 3G-OTH-168003

Also listed as: 641RM12LED · 641RM 12 LED

Brand
Dwyer
Item
Air Velocity Transmitter: 4 mA to 20 mA, 32°F to 140°F, 641RM-12-LED
Category
Air Velocity Transmitters
Available to Order
Trade pricing by quote — replies within 24h
Qty
WhatsApp an engineerMessage via Telegram
No account needed — your quote request goes straight to our engineers. A free account lets you track quotes and re-order faster.
Worldwide Shipping
Air & sea freight
Datasheet on Request
Technical specs
1-Day Quote
Replies within 24h

Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

Dwyer
Manufacturer Part Number
641RM-12-LED
Type
32°F to 140°F, 641RM-12-LED, 250 fpm to 15,000 fpm
Air Velocity Accuracy
+/-3% (32 to 122 °F)
Calibration Certificate
Not Included

Technical Documents

No technical documents available for this product.
Request documentation
Not sure this is the right part? Get a recommendation.

Need installation or engineering help?

Installation, commissioning, maintenance plans, system design, and bundled product + service quotes — one team handles the full scope.
Talk to an engineer

Ask a question

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

Product Description

The DWYER 641RM-12-LED is an air velocity transmitter with a 4 mA to 20 mA output, operating from 32°F to 140°F and measuring 250 fpm to 15,000 fpm. It offers an air velocity accuracy of +/-3% from 32 to 122 °F. This model does not include a calibration certificate.

Frequently Asked Questions

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

The Dwyer 641RM-12-LED measures air velocity from 250 fpm to 15,000 fpm in HVAC, cleanroom, and industrial ventilation systems. It outputs a 4 mA to 20 mA signal for remote monitoring and control of airflow in ducts or fume hoods.

What are the specifications of the Dwyer 641RM-12-LED?

The Dwyer 641RM-12-LED has an air velocity accuracy of +/-3% from 32 to 122 °F, operates from 32°F to 140°F, and measures 250 fpm to 15,000 fpm. It provides a 4 mA to 20 mA output and does not include a calibration certificate.

Where to buy the Dwyer 641RM-12-LED worldwide?

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

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

Mount the Dwyer 641RM-12-LED in a duct with the sensor tip facing airflow. Connect the 4 mA to 20 mA output to a compatible controller or PLC. Ensure ambient temperature stays within 32°F to 140°F. Calibration is recommended periodically; this model ships without a certificate.

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.

You might also need

Burners & Combustion Pumps & Compressors Spare Parts All Products

Compatible alternatives & equivalents

Cross-referenced by specification & description
DWYER Air Velocity Transmitter: 4 mA to 20 mA, 32°F to 140°F, 641RM-12, 250 fpm to 15,000 fpm
Dwyer
DWYER Air Velocity Transmitter: 4 mA to 20 mA, 32°F to 140°F, 641RM-12, 250 fpm to 15,000 fpm
DWYER Air Velocity Transmitter: 4 mA to 20 mA, 32°F to 140°F, 641-12-LED, 250 fpm to 15,000 fpm, LED
Dwyer
DWYER Air Velocity Transmitter: 4 mA to 20 mA, 32°F to 140°F, 641-12-LED, 250 fpm to 15,000 fpm, LED
DWYER Air Velocity Transmitter: 4 mA to 20 mA, 32°F to 140°F, 641-18-LED, 250 fpm to 15,000 fpm, LED
Dwyer
DWYER Air Velocity Transmitter: 4 mA to 20 mA, 32°F to 140°F, 641-18-LED, 250 fpm to 15,000 fpm, LED
DWYER Air Velocity Transmitter: 4 mA to 20 mA, 32°F to 140°F, 641-6-LED, 250 fpm to 15,000 fpm, LED
Dwyer
DWYER Air Velocity Transmitter: 4 mA to 20 mA, 32°F to 140°F, 641-6-LED, 250 fpm to 15,000 fpm, LED
DWYER Air Velocity Transmitter: 4 mA to 20 mA, 32°F to 140°F, 641-24-LED, 250 fpm to 15,000 fpm, LED
Dwyer
DWYER Air Velocity Transmitter: 4 mA to 20 mA, 32°F to 140°F, 641-24-LED, 250 fpm to 15,000 fpm, LED
DWYER Air Velocity Transmitter: 4 mA to 20 mA, 32°F to 140°F, 641-12, 250 fpm to 15,000 fpm
Dwyer
DWYER Air Velocity Transmitter: 4 mA to 20 mA, 32°F to 140°F, 641-12, 250 fpm to 15,000 fpm

More from Dwyer

View all Dwyer parts
Air velocity transmitter with 4-20 mA output and BACnet communication protocol. Measures air velocity from 400 to 1000 fpm with ±3% accuracy over a temperature range of 32°F to 122°F. Suitable for monitoring duct airflow in HVAC systems, cleanrooms, and industrial ventilation. Calibration certificate not included
Dwyer
Air velocity transmitter with 4-20 mA output and BACnet communication protocol. Measures air velocity from 400 to 1000 fpm with ±3% accuracy over a temperature range of 32°F to 122°F. Suitable for monitoring duct airflow in HVAC systems, cleanrooms, and industrial ventilation. Calibration certificate not included
The Dwyer AVUL-5DM1 air velocity transmitter measures airflow from 400 to 1,000 fpm with ±5% accuracy. It provides a 4-20 mA output and Modbus communication for integration into building automation or process control systems. Operating temperature range is 32°F to 122°F. Calibration certificate not included
Dwyer
The Dwyer AVUL-5DM1 air velocity transmitter measures airflow from 400 to 1,000 fpm with ±5% accuracy. It provides a 4-20 mA output and Modbus communication for integration into building automation or process control systems. Operating temperature range is 32°F to 122°F. Calibration certificate not included
This air velocity transmitter measures air flow from 400 to 1000 fpm with an accuracy of ±5%. It provides a 4-20 mA output signal and operates in temperatures from 32°F to 122°F. The unit uses a universal communication protocol and is suited for HVAC and industrial ventilation monitoring. Calibration certificate not included
Dwyer
This air velocity transmitter measures air flow from 400 to 1000 fpm with an accuracy of ±5%. It provides a 4-20 mA output signal and operates in temperatures from 32°F to 122°F. The unit uses a universal communication protocol and is suited for HVAC and industrial ventilation monitoring. Calibration certificate not included
The Dwyer AVUL-3DA1 air velocity transmitter measures air velocity from 400 fpm to 1,000 fpm with an accuracy of ±3%. It features a 4 mA to 20 mA output and a universal communication protocol, operating within a temperature range of 32°F to 122°F. This transmitter is used for monitoring airflow in HVAC ducts, cleanrooms, and ventilation systems. Calibration certificate is not included
Dwyer
The Dwyer AVUL-3DA1 air velocity transmitter measures air velocity from 400 fpm to 1,000 fpm with an accuracy of ±3%. It features a 4 mA to 20 mA output and a universal communication protocol, operating within a temperature range of 32°F to 122°F. This transmitter is used for monitoring airflow in HVAC ducts, cleanrooms, and ventilation systems. Calibration certificate is not included
Air velocity transmitter with ±2% accuracy, 400 fpm range, and BACnet communication protocol. Features an LCD display and operates from 32°F to 122°F. Suitable for measuring and transmitting air velocity in HVAC systems, cleanrooms, and industrial ventilation applications
Dwyer
Air velocity transmitter with ±2% accuracy, 400 fpm range, and BACnet communication protocol. Features an LCD display and operates from 32°F to 122°F. Suitable for measuring and transmitting air velocity in HVAC systems, cleanrooms, and industrial ventilation applications
Air velocity transmitter with universal communication protocol, ±2% accuracy, and LCD display. Measures air velocity up to 400 fpm in a temperature range of 32°F to 122°F. Suitable for HVAC, cleanroom, and industrial ventilation applications. Calibration certificate not included
Dwyer
Air velocity transmitter with universal communication protocol, ±2% accuracy, and LCD display. Measures air velocity up to 400 fpm in a temperature range of 32°F to 122°F. Suitable for HVAC, cleanroom, and industrial ventilation applications. Calibration certificate not included
Air velocity transmitter with 4 mA to 20 mA output, range 1,000 fpm to 4,000 fpm, accuracy +/-3%. Operates at 122°F, uses Modbus communication protocol, no display. Suitable for monitoring duct velocities in HVAC and industrial airflow systems
Dwyer
Air velocity transmitter with 4 mA to 20 mA output, range 1,000 fpm to 4,000 fpm, accuracy +/-3%. Operates at 122°F, uses Modbus communication protocol, no display. Suitable for monitoring duct velocities in HVAC and industrial airflow systems
Air velocity transmitter with 4 mA to 20 mA output, measuring 1,000 fpm to 4,000 fpm with ±3% accuracy. Features an LCD display and BACnet communication protocol. Maximum operating temperature 122°F. Suitable for HVAC, cleanroom, and industrial ventilation airflow monitoring
Dwyer
Air velocity transmitter with 4 mA to 20 mA output, measuring 1,000 fpm to 4,000 fpm with ±3% accuracy. Features an LCD display and BACnet communication protocol. Maximum operating temperature 122°F. Suitable for HVAC, cleanroom, and industrial ventilation airflow monitoring