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    12 Products

    Flow Switches with Sight

    Image of Product. Front orientation. Flow Switches with Sight.
    For monitoring flow at a glance, these switches have a plastic window with a rotor indicator that spins when there’s flow. They activate or deactivate equipment when the flow rate reaches your set point. Tighten or loosen the adjustment screw to choose your set point anywhere within the range. To measure flow, they count how many times the turbine turns as liquid flows through. Use them only with clean, low-viscosity liquids to prevent clogging the turbine and other damage. All are single pole, double throw (SPDT) and can either turn one device from off to on (normally open) or on to off (normally closed).
    These switches are calibrated with water. They can also be used with other liquids but may not measure accurately if their viscosity is significantly different.
    Choose a fitting material that is compatible with the liquid you're running through your line.
    316 Stainless Steel Fitting—Brass and 316 stainless steel fittings resist impact better than polypropylene fittings.
    Polypropylene Fitting—Polypropylene fittings work with a wide range of chemicals. However, they can crack from impact or when overtightened.
    Flow Set Point,
    gpm
    Max. Pressure
    @ Temp.
    Temp. Range,
    ° F
    Max. Switching Current
    @ Voltage
    Mounting
    Position
    End-to-End
    Lg.
    Certification
    Each
    Polypropylene Body with Polypropylene Fittings
     
    1/2 NPT Female
    0.25 to 2.5150 psi @ 70° F20 to 1505 amp @ 120V AC
    5 amp @ 240V AC
    Horizontal3 3/4"CE Marked
    VDE Certified
    4138K1010000000
    0.5 to 5150 psi @ 70° F20 to 1505 amp @ 120V AC
    5 amp @ 240V AC
    Horizontal3 3/4"CE Marked
    VDE Certified
    4138K102000000
    1 to 10150 psi @ 70° F20 to 1505 amp @ 120V AC
    5 amp @ 240V AC
    Horizontal3 3/4"CE Marked
    VDE Certified
    4138K103000000
    1.5 to 15150 psi @ 70° F20 to 1505 amp @ 120V AC
    5 amp @ 240V AC
    Horizontal3 3/4"CE Marked
    VDE Certified
    4138K104000000
     
    316 Stainless Steel Body with 316 Stainless Steel Fittings
     
    1/2 NPT Female
    0.25 to 2.5200 psi @ 70° F20 to 2255 amp @ 120V AC
    5 amp @ 240V AC
    Horizontal3 3/4"CE Marked
    VDE Certified
    4138K105000000
    0.5 to 5200 psi @ 70° F20 to 2255 amp @ 120V AC
    5 amp @ 240V AC
    Horizontal3 3/4"CE Marked
    VDE Certified
    4138K106000000
    1 to 10200 psi @ 70° F20 to 2255 amp @ 120V AC
    5 amp @ 240V AC
    Horizontal3 3/4"CE Marked
    VDE Certified
    4138K107000000
    1.5 to 15200 psi @ 70° F20 to 2255 amp @ 120V AC
    5 amp @ 240V AC
    Horizontal3 3/4"CE Marked
    VDE Certified
    4138K108000000
     
    3/4 NPT Female
    1.5 to 15200 psi @ 70° F20 to 2255 amp @ 120V AC
    5 amp @ 240V AC
    Horizontal5 1/4"CE Marked
    VDE Certified
    4138K109000000
    5 to 50200 psi @ 70° F20 to 2255 amp @ 120V AC
    5 amp @ 240V AC
    Horizontal5 1/4"CE Marked
    VDE Certified
    4138K111000000
     
    1 NPT Female
    1.5 to 15200 psi @ 70° F20 to 2255 amp @ 120V AC
    5 amp @ 240V AC
    Horizontal5 1/4"CE Marked
    VDE Certified
    4138K112000000
    3 to 30200 psi @ 70° F20 to 2255 amp @ 120V AC
    5 amp @ 240V AC
    Horizontal5 1/4"CE Marked
    VDE Certified
    4138K113000000
     
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