VNSCompact Electromagnetic Flow Sensors

VNS Photo

Model VNS is the electromagnetic flow sensor that is compact and does not require any straight pipe length so that it can be easily built in the machines and systems. Chemical solutions including sodium hypochlorite, caustic soda, etc., can be measured. Due to its excellent small flow-rate measurement and repeatability, it has merits in various applications such as water purification plant, distribution reservoir, sterilization system, factory’s wastewater treatment, etc.



Liquid flow measurement application examples
of various machines in wide range of usage fields.




  • ・Compact and excellent cost performance
  • ・Outstanding reliability with no moving parts
  • ・Suitable for use in machines
  • ・Easy-to-check 2-color LED(status) indicator
  • ・2 selectable outputs (Unitpulse,High-density pulse,Warning,Switch)

Examples of use


Measurement principle



Principal of measurement Electromagnetic type with Faraday’s law of electromagnetic induction
Accuracy assured flow-rate range *2 0.05~1 L/min 0.5~10 L/min 3.0~60L/min
Measurement starting flow-rate 0.025 L/min 0.25 L/min 1.5 L/min
Piping connection Socket type union joint (16A) Socket type union joint (16A) Socket type union joint (20A)
Accuracy *3 Unit pulse output ±2.0%RS (100~20% of the maximum flow-rate) ±0.4%FS (20~5% of the maximum flow-rate)
Response time (at 63% response) Standard: 2 seconds. Setting within the range of 0.1600 seconds is available.
Fluid temperature range 0~40°C, freezing must be avoided. (VNS05 can resist 15 minutes per day of 95°C, whereas its accuracy is out of guarantee.
Measurable fluid
  • Sodium hypochlorite (Concentration of 1~12%)
  • Sodium hydroxide aqueous solution (Concentration of 10~25%)

For other kind of liquid, by selecting with reference to the following major materials of the fluid-touching materials, please consult with us for suitability confirmation.

Working ambient temperature range -20~60°C
Ambient temperature range for storage -20~70°C
Fluid pressure range 0~1MPa
Signal cable
  • Standard cable length 0.5m
  • 4-wires (AWG26) Line 1: Power + line Line 2: Power – line Line 3: Output 1 Line 4: Output 2
  • Top of the each: Soldered stranded wire
Display 1 LED display at the flowsensor’s body

  • Green: Flow-rate indication (Indication with blinking speed of 3 steps)
  • Red: Alarm indication (Indication of abnormality with numbers of blinking)
Place of installation Indoor installation (In case of outdoor installation, please take necessary measure so that the flowsensor is not exposed to rain and sun beam directly.)
Enclosure IPX4
Corresponding standard CE Standard *1
Fluid-touching materials

Main body: PEEK resin

Electrodes: Pure titanium (2 kinds)O-ring: For sodium hypochlorite, etc. – FKM (Fluoro rubber)

For Sodium hydroxide aqueous solution, etc. — EPDM (Ethylene propylene rubber)

Installation position Free (Vertical piping is recommended.)

*1 Except EN61000-4-5(surge) because VN series is intended to utilize as the built-in flowsensor of a machine,etc. *2 (Minimum flow-rate ~ maximum flow-rate) *3 For constant flow without pulsation.


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Related information

Introduction of the latest technology |Measuring microflows Research on microflow sensors



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VNS Manual
VNS Specifications



Specifications may vary by country, about which please confirm at the time of inquiry.

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・Specifications are subject to change without notice.
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