S401 & S421 Thermal Mass Flow Sensors

S401 & S421 Air/Gas Flow Sensors

S401 and S421 are a new generation of thermal mass flow meters with many improvements over the previous S 400 / S 420 models. The new designs both incorporate improved accuracy, a much higher sampling rate, up to two user selectable calibrations for alternate gases and a new colour display with bluetooth interface for remote sensor configuration.

The S401 is an insertion type sensor with standard G1/2″ male thread and a choice of stem lengths to suit line sizes up to DN300. Larger line sizes can be accommodated on request. The S421 is the inline version with threaded or flanged connections in sizes DN 32 to DN80 and incorporates an integral flow conditioner.

Both provide dual isolated 4-20mA (flow & temperature), pulse and SDI (SUTO Digital Interface) as standard with options for Modbus/RTU communication to interface with common plant control systems and other SUTO products.

  • Insertion or inline designs
  • Pressure range up to 5.0MPa
  • Output 4-20mA, SDI, Modbus/RTU
  • Optional colour display
  • Bluetooth interface

The units can be supplied calibrated for up to 2 standard gases such as Air, Carbon Dioxide, Oxygen, Nitrogen, Nitrogen Oxide, Argon, Natural Gas, Hydrogen, Helium and Propane. Other gases or gas mixes on request.

With a maximum pressure rating of 5.0MPa (requires high pressure installation kit), S401 offers accurate measurement and fast response to changing flow conditions in a wide range of industrial processes.

Bidirectional measurement capability is built into the S401/S421 series with separate consumption counters for each direction. Whether the standard or high accuracy (1%) version is chosen, S401 and S421 offer outstanding repeatability of +/-0.25% of reading.

Data Sheet

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+44 (0) 1443 772500 / 02922 780798

Red Dragon Limited T/A
Measure Monitor Control
Unit 15 Abergorki Industrial
Ynyswen Road
South Wales
CF42 6DL
United Kingdom
EORI: GB791056521000

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