Miniature Rotating-Paddle Level Sensor

Model R7 Series

The Model R7 Series miniature bin level sensors have been developed for use with plastic molding or injection machines and extruders. It can also be built into equipment such as grain processing machines. They are the smallest, lightest-weight and lowest cost unit of its type available, but it gives outstanding, reliable service.
There are two versions of the R7 level sensor. One version, the R7-X series, is for indoor use while the other, the R7-Z series is designed for outdoor use.

Main Features

  • Miniature size and low cost
    A special miniature size motor is employed. By using a resin-molded housing this is the world's smallest and lightest-weight bin level sensor.
  • Easy torque adjustment
    Torque is adjustable to the most appropriate value by simply removing the cover and changing a spring position.
  • Reliable Design
    A built-in, specially wear-proofed magnetic slip system is employed to avoid damage to the motor. This system protects the motor even when large accidental forces are received by the sensing paddle.
  • Easy maintenance and repair
    The internal mechanism can easily be removed from the main unit for repair or replacement.

    Principle of Operation

    When line voltage is applied to the R7, the small motor powers a revolving shaft with a paddle mounted on it. When the powder level inside the container reaches the revolving paddle, the rotation is halted and the motor rotates around the shaft and activates an isolated SPDT (Single Pole, Double Throw) micro switch. This removes power from the motor so it stops rotating and an alarm signal is provided.
    A falling powder level resets the motor's position and the micro switch restores the revolving action.

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