Variable Area Flow Meter / Rotameter

Miniature Metal Tube Variable Area Flowmeter / Rotameter - MMT18 / MMT19

iSOLV MMT18 VA flowmeter measures volumetric flow rate of liquid and gases that operates on the float principle. It features a metal tube, in which a float is allowed to move freely up and down. The float reaches a stable position when the upward force exerting by the flowing liquid equals the weight of the float. The float position is transmitted by a magnetic coupling system to the scale. The rotational movement of the follower magnet system transmitted to the indicator is linearised and the flow rate is indicated directly on the scale.

Miniature Metal Tube Variable Area Flow Meter Working Principle


  • Suitable for liquids and gases

  • Suitable for installation in which flow direction is from bottom to top

  • Tapered metering section of rugged all-metal construction

  • Standard Features - MMT18
    - With horizontal connections
    - A needle valve at the inlet or bottom front of connection block

  • Option
    - Can be supplied without valve, or with outlet needle valve at the top connection block (outlet)
    - A maximum of two adjustable limit switches (L1, L2). The set limits are indicated on the scale.
    - Addition of a differential pressure regulator to maintain constant flow rate at fluctuating inlet/outlet pressure

  • Standard Features - MMT19
    - With vertical connections
    - Without needle valve

  • Option
    A maximum of two adjustable limit switches (L1, L2). The set limits are indicated on the scale.

  • Applications

    • Chemical

    • Waster / Wastewater

    • Marine / Offshore

    • Pulp and Paper

    • Pharmaceutical

    • Food and Beverage

    • Oil and Gas


    Technical Details
    Full-scale Range (100% Values)
    Water at 20°C (68°F) 3 to 100 l/h (0.013 to 0.44 US GPM)
    Air at 1.013 bar abs., 20°C
    (14.7 psia, 68°F)
    50 to 3400 l/h (0.031 to 2.11 SCFM)
    Turn-down Ratio 10:1
    Accuracy Class
    (to VDI/VDE Code 3513,
    Sh. 2)
    E a = AC (25 + 0.75)/F
    E a = Error (% actual) F = % Full scale flow AC = Accuracy Class
    Scale Graduation Flow units
    Max. Allowable Operating
    Pressure at 20°C (68°F).
    130 bar (1885 psig)
    Test pressure is 1.3 times the specified operating pressure.
    Information on higher pressure levels supplied on request
    Max. Process Temperature
    Without Limit Switch Option – 80°C to +150°C (–112°F to +302°F)
    With Limit Switch Option
    (Ambient Temperature Ta)
    Ta < 40°C
    (< 104°F)
    Ta < 50°C
    (< 122°F)
    Ta < 60°C
    (< 140°F)
    145°C 293°F 135°C 275°F 125°C 257°F
    Standard ¼” NPT female thread
    Connection Blocks, Valve, Plug CrNi steel 1.4571 (316Ti)
    Housing Die-cast zinc
    Cone, Float CrNi steel 1.4571 (316 Ti)
    Gaskets PTFE, other upon request
    Limit Switch Type: SJ2-SN
    Number, Max. 2
    Electrical Connection Right-angle plug, style to DIN 43650/ISO 4400, with PG 11 cable gland
    Max. Signal Cable Length 1.5 m (5 ft) non-detachable
    Protection category to EN 60529/IEC 529 IP 65, equivalent to NEMA 12 and 13
    An isolation switching amplifier is required to operate the SJ2-SN
    Note: Specifications are subject to change without notice.


    For all inquiries, you may contact us through Telephone, Email or Live Chat Support.

    Operating Hours

    Monday to Friday: 8.00am to 5.30pm

    Technical Support (After Office Hours)

    Tel: (65) 9876 6258

    Contact Information

    By Phone / FaxBy Email
    Tel: (65) 6553 0366
    Fax: (65) 6553 0828

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