OPTIFLUX 4300 is an electromagnetic flow meter designed for measuring the flow of hot and cold water. Its electromagnetic technology gives it many advantages : no moving parts (no mechanical wear), high measuring dynamics, low pressure drop, low start-up flow and insensitivity to suspended particles.
It can also be used for glycol water measurement (without MID approval).


  • Measures all conductive liquids with conductivity > 20 µS/cm
  • MID class 2 approval (only for water)
  • Full range from DN 25 mm to DN 300 mm
  • Compatible with pulse input computers
  • Temperature range from +0°C to +180°C in separate version
  • Analogue output by default
  • Other optional communication bus
  • General
    Applicationheating / cooling | Heat transfer fluid with conductivity > 20 µS/cm
    ApprovalMID (DE-13-MI004-PTB005) only for water
    Ambient classMID class E2 + M2
    Ambient temperature°C-40 ... +65 °C
    Power supply100 … 230 VAC | 50 ... 60 Hz
    Mounting positionall positions
    Protection classIP 67
    Interfacepulse output ; analogue output
    Digital outputs (optional)fieldbus, Modbus RTU, Profibus, PROFINET
  • Temperature range
    Temperature range compact version°C0 ... +140
    Temperature range separated converter version°C0 ... +180
  • Basic features
    Nominal flowrateQpm³/h1640100250400400100016002500
    Nominal diameterDNmm255065100125150200250300
    Minimum flow rateQim³/h0.
    Maximum flow rateQsm³/h2050125312.5500500125020003125
    Default nominal pressurePNbar404016161616161616
    Pulse weightl/pulse111010100100100100100
    Analog output at 20 mAm³/h2050125312.5500500125020003125
  • Dimensions
    Nominal flowrateQpm³/h1640100250400400100016002500
    Nominal diameterDNmm255065100125150200250300
    Flanges nominal pressurebar404016161616161616
    Flange diametermm115165185220250285340395445
    Number of screwholes444888121212

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