Dial Instruments Pte Ltd
Level Measurement Solutions for Petrolchemical, Pharmaceutical,
Marine & General Industries
Subpage :: Masthead
Guard Float Sensor FC



Water treatment facilities and applications with limited space above the tank


  • Easy adjustment
    • Set points are easily adjusted by changing cable length.
      Inverting the float reverses operation.
  • Ideal for small space
    • Cable suspended design allows easy installation in limited space.
  • High reliability and safety
    • Among high accuracy reed switches, only those that meet our original standards are used to ensure stable operation over the long service life.
  • Easy maintenance
    • Easily removed from the tank just by lifting the sensor.

Principle of Operation

Principle of Operation  
  • The electrode is suspended from the detector in the pipe using coaxial cable. The cable end is wound on the spool and then connected to an external device through the slip ring.
  • When inductance and the detected capacitance tune to the frequency of the voltage applied from the controller, the parallel resonance circuit resonates, causing the highest high frequency voltage to be applied to the electrode.
  • The high frequency voltage on the measurement electrode varies with the measured capacitance, and so does the output voltage.
  • The reference voltage is adjusted such that the centre of the electrode becomes the zero point, and the bridge circuit is made to output zero at this point.
  • When a voltage (+E or ?E) is applied to the electrode due to level change, the servo motor rotates normally or reversely so that the bridge is always balanced, causing the electrode to rise or fall with the material surface.