Dwyer Omega – Series 641 Heated Mass Flow Air Velocity Transmitter ± 16 Ranges, NIST Options

Dwyer Omega – Series 641 Heated Mass Flow Air Velocity Transmitter ± 16 Ranges, NIST Options

The Series 641 Air Velocity Transmitter is the ideal instrument for monitoring air flow. This transmitter uses a heated mass flow sensor which allows for precise velocity measurements at various flow rates and temperatures. The 641’s 16 field selectable ranges provides it the versatility to be selected for several air flow applications. The optional LED produces a complete, low-cost solution for local indication of air flow.

Accuracy

± 3 %

Accuracy Detail

3% FS process gas: 32 to 122°F (0 to 50°C); 4% FS process gas: -40 to 32°F and 122 to 212°F

Air Velocity, Max

15000 FPM

Air Velocity, Min

250 FPM

Compliance

CE

Electrical Connection

Screw Terminal

Electrical Output

4 to 20 mA

Filter

0.5 to 15 s (Selectable)

Loop Resistance

600 Ω max

Media Compatibility

Argon, Carbon dioxide, Clean Dry Air, Helium, Nitrogen, Non-Corrosive Dry Gases

Mounting Orientation

None

Number of Wires

4

Operating Temperature, Max

140 °F

Operating Temperature, Min

32 °F

Output Detail

4 to 20 mA, isolated 24 V source, 3 or 4-wire connection

Power Consumption

300 mA

Pressure Limits

Up to 100 psi

Process Connection Size

1/2 in

Process Connection Type

NPT Male

Process Temperature, Max

212 °F

Process Temperature, Min

-40 °F

Relative Humidity

Non-Condensing

Response Time

1.5 s to 95%

Response Time Note

Flow: 1.5 s to 95% of final value (output filter set to minimum)

Supply Power Note

12 to 35 Vdc, 10 to16 Vac. 1.5 A rating required on supply due to initial power surge drawn by transmitter

Supply Power Type

AC/DC

Supply Voltage

10 to 16 Vac, 12 to 35 Vdc