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Dwyer 641B-4 Air Velocity Transmitter

The Series 641B Air Velocity Transmitter uses a heated mass flow sensor suitable for dirty air flow applications.

  • Accuracy: 5% FS process gas: 32 to 122 F
  • Outputs: 4-20 mA
  • Power Requirments: 12 to 35 VDC, 10 to 16 VAC
  • Current Consumption: 300 mA max*
Price: $750.45
    Part# 641B-4
    ServiceAir and compatible, non-combustible gases
    Accuracy5% FS process gas: 32 to 122 F
    Response TimeFlow: 15 s to 95% of final value (output filter set to min)
    Temperature LimitsProcess: -40 to 176 F (-40 to 80 C) Ambient: 32 to 140 F (0 to 60 C)
    Humidity LimitNon-condensing
    Power Requirments12 to 35 VDC, 10 to 16 VAC
    Output FilterSelectable 05-15 s
    Loop Resistance600 Ω max
    Current Consumption300 mA max*
    Outputs4-20 mA
    Electrical ConnectionsScrew terminal
    Enclosure RatingDesigned to meet NEMA 4X (IP66)
    Mounting OrientationUnit not position sensitive
    ApprovalsRoHS
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