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Starting at $1,182.90CAD
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Dwyer

641 Air Velocity Transmitter

High Accuracy, Field Selectable Ranges

Starting at
$1,182.90CAD
Have questions? We're here to help!
Have questions? We're here to help!
Configure

 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.

• Ranges from 250 FPM (1.25 MPS) to 15,000 FPM (75 MPS)
• Optional bright LED display
• Easy push button set-up
• Compact housing
• 4 to 20 mA output
• Digital filter for signal damping
Weight13.3 oz (377 g).
Resolution1 FPM, 0.01 MPS (10 FPM @ 10,000 and 15,000 FPM ranges).
Display4-1/2 digit 1/2" red LED.
Optional Display Version
Agency ApprovalCE
Weight12.6 oz (357.2 g).
Mounting OrientationUnit not position sensitive. Probe must be aligned with airflow.
Enclosure RatingDesigned to meet NEMA 4X (IP66) for non LED models only.
Process Connections1/2" male NPT.
Electrical ConnectionsScrew Terminal
Current Consumption300 mA max.
Loop resistance600 Ω max.
Output FilterSelectable 0.5-15 s.
Output Signal4 to 20 mA, isolated 24 V source, 3 or 4-wire connection.
Power Requirements12 to 35 VDC, 10 to 16 VAC. 1.5 A rating required on supply due to initial power surge drawn by transmitter.
Humidity LimitsNon-condensing.
Pressure Limit100 psi (6.89 bar) maximum.
Temperature Limits:Process: -40 to 212°F (-40 to 100°C). Ambient: 32 to 140°F (0 to 60°C).
Response TimeFlow: 1.5 s to 95% of final value (output filter set to min.).
Accuracy3% FS Process gas: 32 to 122°F (0 to 50°C); 4% FS Process gas: -40 to 32°F & 122 to 212°F (-40 to 0°C & 50 to 100°C).
ServiceClean air and compatible, non-combustible gases.
• Exhaust stack flow monitoring
• Air control in drying processes
• HVAC air velocity measurements
• Fan supply and exhaust tracking
• Clean room fresh air supply
• Ensure proper lab hood exhaust flow rates
  • Thumbnail of document Data Sheet - 641 Air Velocity Transmitter
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    Data Sheet - 641 Air Velocity Transmitter

    Download
  • Thumbnail of document Manual - 641 Air Velocity Transmitter
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    Manual - 641 Air Velocity Transmitter

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